291 results on '"Lewis GK"'
Search Results
2. Baculovirus-Derived HIV-1 Virus-Like Particles (VLP) Activate Dendritic Cells and Are Cross-Presented to Induce In Vitro T-Cell Response
- Author
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Lewis-Kamin R, Marincola FM, Aricò E, Tornesello ML, Buonaguro L, Gallo RC, Lewis GK, and Buonaguro FM
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Immunologic diseases. Allergy ,RC581-607 - Published
- 2005
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3. Trigger Point Injections Followed by Immediate Myofascial Release in the Treatment of Pelvic Floor Tension Myalgia
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Lewis, GK, primary, Chen, AH, additional, Leon, MG, additional, and Carrubba, AR, additional
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- 2021
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4. Knowns and Unknowns of Assaying Antibody-Dependent Cell-Mediated Cytotoxicity Against HIV-1
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Lewis, GK, Ackerman, ME, Scarlatti, G, Moog, C, Robert-Guroff, M, Kent, SJ, Overbaugh, J, Reeves, RK, Ferrari, G, Thyagarajan, B, Lewis, GK, Ackerman, ME, Scarlatti, G, Moog, C, Robert-Guroff, M, Kent, SJ, Overbaugh, J, Reeves, RK, Ferrari, G, and Thyagarajan, B
- Abstract
It is now well-accepted that Fc-mediated effector functions, including antibody-dependent cellular cytotoxicity (ADCC), can contribute to vaccine-elicited protection as well as post-infection control of HIV viremia. This picture was derived using a wide array of ADCC assays, no two of which are strictly comparable, and none of which is qualified at the clinical laboratory level. An earlier comparative study of assay protocols showed that while data from different ADCC assay formats were often correlated, they remained distinct in terms of target cells and the epitopes and antigen(s) available for recognition by antibodies, the effector cells, and the readout of cytotoxicity. This initial study warrants expanded analyses of the relationships among all current assay formats to determine where they detect overlapping activities and where they do not. Here we summarize knowns and unknowns of assaying ADCC against HIV-1.
- Published
- 2019
5. 1533 Robotic-Assisted Laparoscopic Excision of Deep Infiltrating Endometriosis Involving the Ureter
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Lewis, GK, primary and Mahmoud, M, additional
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- 2019
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6. Aspirations and Occupational Opportunities for Aboriginals
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Lewis, GK
- Published
- 1974
7. Structured particles for antigen presentation
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Buonaguro, L, primary, Tornesello, ML, additional, Lewis, GK, additional, and Buonaguro, FM, additional
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- 2006
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8. Baculovirus-Derived HIV-1 Virus-Like Particles (VLP) Activate Dendritic Cells and Are Cross-Presented to Induce In Vitro T-Cell Response
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Buonaguro, L, primary, Tornesello, ML, additional, Aricò, E, additional, Marincola, FM, additional, Lewis-Kamin, R, additional, Gallo, RC, additional, Lewis, GK, additional, and Buonaguro, FM, additional
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- 2005
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9. Antigen structural requirements for immunoglobulin isotype switching in mice
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Chen, P, Nitecki, DE, Lewis, GK, and Goodman, JW
- Abstract
L-Tyrosine-p-azobenzene-p-arsonate (RAT) is immunogenic and serves as a carrier for anti-hapten antibody responses in guinea pigs, rats, and mice. However, the murine anti-N-2,4-dinitrophenyl (DNP) plaque-forming cell (PFC) response to the bifunctional antigen 2,4-dinitrophenyl-6-amino-caproyl-L- tyrosine-p-azobenzene-p-arsonate (DNP-SAC-RAT; or BI-1) is extremely weak (2,000-4,000 PFC/spleen) and exclusively IgM in both primary and secondary responses. The 6-amino-caproyl group serves as a spacer in this antigen between the DNP haptenic and RAT carrier epitopes. In view of recent evidence indicating that different T helper cells synergize for optimal antibody responses, a trifunctional antigen, N-2,4- dinitrophenyl-6-amino-caproyl-L-tyrosine-p-azobenze-p-arsonate-(proline)9-L- tyrosine-p-azobenzene-p-arsonate (DNP-SAC-RAT-PRO(9)-RAT; or TRI), was prepared to investigate the effect of adding a second RAT epitope to BI-1. The nonaproline spacer between the two RAT epitopes in TRI is assumed to be a rigid rod of approximately 28 A. TRI induced about twice as many PFC as BI-1 in primary responses of A/J mice, and induced both IgM and IgG PFC in secondary responses. Furthermore, TRI induced IgG PFC responses in mice primed with p-azobenzene-p-arsonate-keyhole limpet hemocyanin, BI-1, or RAT, whereas boosting with BI-1 failed to induce IgG PFC, even in mice primed with TRI. These findings indicate that the minimum antigen structural requirements for inducing IgG PFC in mice are two carrier epitopes and one haptenic epitope. In addition, priming with a mono-epitope carrier (RAT) is sufficient preparation for IgG responses to a trifunctional immunogen. Because TRI differs from BI-1 by the (proline)(9) spacer as well as the additional RAT epitope, two other compounds, N-2,4-dinitrophenyl-6-amino- caproyl-(proline)(9)-L-tyrosine-p-azobenzene-p-arsonate (DNP-SAC-PRO(9)-RAT; or BI-2) and N-2,4-dinitrophenyl-6-amino-caproyl-(proline)(9)-L-tyrosine-p- azobenzene-arsonate (DNP-SAC-RAT-PRO(10); or BI-3), were prepared to evaluate the possible role of the spacer in the observed responses. BI-2, but not BI-3, induced IgG as well as IgM PFC in TRI-primed mice. However, BI-2 failed to induce IgG responses in RAT-primed mice, indicating that TRI and BI-2 were not equivalent immunogens. Because anti-prolyl antibodies had been found in guinea pigs immunized with N-2,4-dinitrophenyl-(proline)10-L-tyrosine-p- azobenzene-p-arsonate (DNP-PRO(10)-RAT), it seemed possible that priming with TRI might induce anti-prolyl antibodies, which, in turn, could cross-link BI-2 molecules into aggregates containing at least two carrier epitopes. To help resolve this question, mice were immunized with acetyl-(proline)10-L- tyrosine-p-azobenzene-p-arsonate and boosted with BI-2. IgG PFC responses were detected, suggesting that anti-prolyl antibodies were indeed responsible, because priming with RAT and boosting with BI-2 did not induce IgG formation. Accordingly, the observations that IgG responses in RAT-primed mice were induced only by TRI and not by any of the bifunctional antigens indicate that two carrier epitopes per antigen molecule are indeed required for IgG induction. They also provide indirect evidence for synergistic help in the switching of immunoglobulin isotypes.
- Published
- 1980
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10. Carrier-directed anti-hapten responses by b-cell subsets
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Lewis, GK and Goodman, JW
- Abstract
The capacity of the trinitrophenyl (TNP) haptenic group, coupled to a series of chemically dissimilar carriers, to cross-stimulate putative T- dependent and T-independent murine B-cell subpepulations was determined by using an in vitro limiting dilution technique to generate primary IgM responses. It was found that TNP-Ficoll and TNP-dextran, two T- independent antigens with little or no polyclonal mitogenicity, stimulate the same population of anti-TNP precursors, which is distinct from the precursor population activated by TNP-bacterial lipopolysaccharide (LPS), a T-independent polyclonal mitogen, or TNP-horse erythrocytes (HRBC), a T-dependent antigen. On the other hand, TNP-LPS and TNP-HRBC activate the same precursor population, indicating that LPS can substitute for the T- cell signal in T-dependent B-cell responses, whereas nonmitogenic T- independent antigens cannot. However, the cumulative evidence from this and other laboratories strongly indicates that LPS and T-dependent antigens activate B cells by different mechanisms. Of particular interest, LPS is incapable of activating B cells responsive to weakly- or nonmitogenic T-independent antigens. Based on clonal burst size, T-dependent antigens are capable of inducing greater antigen-specific B-cell proliferation than T-independent antigens. However, TNP conjugates of Ficoll and dextran, which are relatively poor inducers of polyclonal B-cell activation, induced larger anti-TNP clones than did TNP-LPS, a strong polyclonal mitogen. The findings reinforce the evidence favoring existence of multiple B- cell subpopulations with distinctive activation pathways. They also strengthen the proposition that a given B-cell subset can be activated by more than one mechanism.
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- 1977
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11. Arsonate-specific murine T cell clones. I. Genetic control and antigen specificity
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Hertel-Wulf, B, Goodman, JW, Fathman, CG, and Lewis, GK
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The antigen-induced proliferative response of lymph node cells (LNC) from mice sensitized to the monofunctional antigen L-tyrosine-p-azobenzenearsonate (ABA-Tyr) was used to monitor genetic control. All strains tested mounted significant responses, but those that were H-2(b) at both the I-A and I-E loci [B10., B6., B10.A(18R), A.BY, and C3H.SW] gave consistently weaker responses than other haplotypes. The F(1) progeny of matings between high and low responder phenotype parents (DBA/2 and B6, respectively) were high responders, establishing the dominance of the responder trait. Proliferative responses of LNC to ABA-Tyr were blocked by the appropriate anti-Ia monoclonal reagents. For example, B10.A(4R) LNCI (I-A(k), I-E(b)) were blocked by anti-I-A(k), whereas B10.A(3R) LNC (I-A(b), I-E(k)) were blocked by anti-I-E(k). Long-term cultures of T cell lines specifically reactive to ABA-Tyr were established from LNC of A/J mice immunized with ABA-Tyr and were cloned by limiting dilution. The proliferative responses to ABA-Tyr of 14 out of 15 clones tested were I-A restricted on the basis of activation by antigen-presenting cells from appropriate recombinant strains and the blocking activity of the monoclonal anti-Ia antibodies. The response of the other clone was I-E restricted. The fine antigen specificity of the clones was studied using structural analogs of the homologous antigen to induce proliferation. The clones could be divided into three types with respect to responsiveness to ABA-histidine (ABA-His). One group responded about equally well to ABA-His and ABA-Tyr. A second set responded less strongly to ABA-His than to ABA-Tyr, while the third showed no response above background to ABA- His. In all instances, the ABA-His-responding clones discriminated exquisitely between the 2-azo and 4-azo histidine isomers, responding only to the 4-azo compound. These T cell clones provide extremely useful tools for studies of T cell specificity, antigen recognition and lymphoid cell interaction systems.
- Published
- 1983
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12. Idiotype profile of an immune response. I. Contrasts in idiotypic dominance between primary and secondary responses and between IgM and IgG plaque- forming cells
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Conger, JD, Lewis, GK, and Goodman, JW
- Abstract
The primary response of A/J mice to p-azobenzenearsonate-keyhole limpet hemocyanin (ABA-KLH) was investigated. A day-by-day analysis at the plaque- forming cell (PFC) level was performed, with inhibition by anti-cross- reactive idiotype (CRI) serum to determine percentage of CRI(+) PFC. A regular pattern in the dynamics of Id (idiotype) dominance was observed. Just as in the NP-b and NP-a systems (9, 12), the major Id (CRI) is more dominant in primary than in secondary or hyperimmune responses. This trend is more apparent in IgG PFC which are generally 80-95 percent CRI(+) at day 10 in the primary response but only 30-40 percent CRI(+) at day 10 in secondary or hyperimmune responses. A somewhat different pattern is seen with IgM PFC. These may reach a peak of 85 percent CRI(+) in the primary response, but secondary or hyperimmune IgM PFC, which are lower in numbers than IgG PFC, remain high in CRI content at approximately 70 percent. The PFC data on extent of id dominance in secondary or hyperimmune responses is fully compatible with previously reported serological data by others. Analysis of IgG PFC by hapten inhibition indicated that heterogeneity was in the order secondary PFC {greater than} primary PFC {greater than} hybridoma AK-2.2 PFC with H(75)/H(25) values of 22.9, 6.2, and 2.7, respectively; where H(75) and H(25) are the hapten concentrations required to give 75 percent and 25 percent of inhibition of PFC, respectively. Hapten inhibition data also suggested that secondary IgG PFC were 10 times higher in median binding avidity for ABA-L-tyrosine than primary IgG PFC. The kinetic analysis strongly indicated that CRI(+) IgM PFC were preferentially switched to IgG PFC in the primary response. In both studies, the CRI content of the earliest-appearing IgG PFC was significantly higher than that of IgM PFC on that day. For example, in one case IgM PFC were 60 percent CRI + on day 6 whereas IgG PFC were 100 percent CRI(+). The high Id dominance and selective isotype switching may have either a B or a T cell basis.
- Published
- 1981
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13. Purification of functional, determinant-specific, idiotype-bearing murine T cells
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Lewis, GK and Goodman, JW
- Abstract
Strain A/J mice immunized with azobenzenearsonate (ABA)-mouse IgG conjugates develop suppression for anti-trinitrophenyl(TNP) responses to doubly conjugated (ABA,TNP) proteins. This suppression is specific for the ABA epitope and is mediated by T cells in cell transfer experiments. ABA-binding T cells from suppressed animals were purified by a two-stage procedure in which B cells were removed from spleen cell populations by adherence to plastic surfaces coated with anti-mouse Ig antibody, followed by binding the nonadherent population (more 95 percent Thy-1-positive) to surfaces coated with ABA-protein conjugates. Approximately 90 percent of the cells recovered by temperature-dependent elution from the ABA plates (similar to 2 percent of the spleen cells) bound antigen immediately afterward, and up to 50 percent of the cells bound anti-cross-reactive idiotype antibody. On the other hand, the nonadherent T-cell population was completely negative in the antigen- binding and idiotype assays. Another distinguishing feature of the two T-cell populations was that 78 percent of the adherent cells, but only 2 percent of the nonadherent cells, were Ia positive, although the specific I-region marker(s) expressed on the cells was not identified. The biological function of the antigen-binding T cells was investigated using a standard cell transfer protocol. Suppressor cells were enriched in the adherent population by a factor of at least 25, establishing that functional, epitope-specific, idiotype-bearing T cells can be significantly purified by this procedure. Note Added in Proof. We have recently isolated two types of ABA-binding molecules biosynthetically labeled with (35)S-methionine from NP-40 lysates of purified antigen-specific T cells. The molecules were purified by adsorption onto an ABA-Sepharose immunoadsorbent followed by elution with 9 M urea. Autoradiograms of SDS-PAGE of the eluates revealed components with tool wt of approximately 60,000 and 33,000 dahons. These molecules were not present in eluates from a bovine IgG-Sepharose control immunoadsorbent and thus represent specific ABA-binding products synthesized by T cells.
- Published
- 1978
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14. The use of the patch graft in extensive skin loss
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Lewis Gk
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medicine.medical_specialty ,business.industry ,Transdermal Patch ,Transplants ,Skin Transplantation ,Skin transplantation ,Plaque, Atherosclerotic ,Surgery ,Skin loss ,Medicine ,Humans ,business ,Patch graft ,Burns - Published
- 1953
15. Congenital neurogenic malformation of the faucial tonsil
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Costanzo Va, Lewis Gk, and Gottstein Wk
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Pathology ,medicine.medical_specialty ,business.industry ,Pharynx ,Palatine Tonsil ,Normal tissue ,Infant, Newborn ,Second pharyngeal pouch ,General Medicine ,Anatomy ,Hyperplasia ,medicine.disease ,Infant, Newborn, Diseases ,medicine.anatomical_structure ,Otorhinolaryngology ,Notochord ,Faucial tonsil ,medicine ,Humans ,Surgery ,business ,Infiltration (medical) - Abstract
TONSILLAR growths, particularly those of congenital origin, form a highly controversial problem. It is the consensus among investigators that congenital tumors are very rare and, as a search of the literature reveals, are omitted from many comprehensive works on pathology. Many congenital tumors once described as growths have later been interpreted as hyperplasia of normal tissue. A few cases of teratomas and dermoid cysts have been described but not sufficiently analyzed from the histological point of view. Blair,1however, points to the possibility that congenital tumors are of fairly frequent occurrence but, being easily detached, are often lost without detection. Meyer2and Grunwald2ahave demonstrated in chicken and human embryos the relationship between the formation of the notochord and the tissues of the primitive pharynx. Since the faucial tonsil results from an infiltration of lymphocytes into the dorsolateral wall of the second pharyngeal pouch, the invasion of
- Published
- 1951
16. Burns from electricity
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Lewis Gk
- Subjects
Injury control ,Accident prevention ,business.industry ,Poison control ,Human factors and ergonomics ,Articles ,medicine.disease ,Suicide prevention ,Occupational safety and health ,Electricity ,Injury prevention ,Medicine ,Humans ,Surgery ,Medical emergency ,business ,Burns - Published
- 1950
17. VARIANT-SPECIFIC MONOCLONAL AND GROUP-SPECIFIC POLYCLONAL HUMAN-IMMUNODEFICIENCY-VIRUS TYPE-1 NEUTRALIZING ANTIBODIES RAISED WITH SYNTHETIC PEPTIDES FROM THE GP120 3RD VARIABLE DOMAIN
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Laman, Jd, Schellekens, Mm, Abacioglu, Yh, Lewis, Gk, Tersmette, M., Ron Fouchier, Langedijk, Jpm, Claassen, E., and Boersma, Wja
18. Feast for the senses: leveraging culture as a competitive advantage in the wine sector
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Lewis, GK, Lehman, KF, Lewis, GK, and Lehman, KF
- Abstract
In the wine sector, opportunities exist to augment the wine offering with a range of cultural products and activities available at the cellar door or vineyard, with a view to creating a hedonistic consumer experience. The assumption is that drinking premium wine, consuming fine food and attending cultural events is an attractive offering, particularly for the middle-aged, educated, and high-income segment. In this paper we explore how and why wine producers adopt this marketing strategy, through the use of four pilot case studies. Preliminary findings suggest that leveraging culture allows wine producers to enhance the wine tasting experience, attract a wider range of consumers, and extend and diversify their brand.
19. The role of immunoglobulin receptors and T cell mediators in B lymphocyte activation. I. B cell activation by anti-immunoglobulin and anti-idiotype reagents
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Primi, D, primary, Lewis, GK, additional, and Goodman, JW, additional
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- 1980
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20. Antibodies to the scrapie protein decorate prion rods
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Barry, RA, primary, McKinley, MP, additional, Bendheim, PE, additional, Lewis, GK, additional, DeArmond, SJ, additional, and Prusiner, SB, additional
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- 1985
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21. Field Experience in a Clinical Specialty
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Lucas P and Lewis Gk
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Medical education ,Graduate nurse ,Field experience ,Specialty ,General Medicine ,Psychology ,General Nursing - Published
- 1955
22. SCALPEL FOR PARING MARGINS OF CLEFT PALATE
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Lewis Gk
- Subjects
Cleft Palate ,business.industry ,Humans ,Medicine ,Dentistry ,Surgery ,business - Published
- 1949
23. A comprehensive engineering strategy improves potency and manufacturability of a near pan-neutralizing antibody against HIV.
- Author
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Sajadi MM, Abbasi A, Tehrani ZR, Siska C, Clark R, Chi W, Seaman MS, Mielke D, Wagh K, Liu Q, Jumpa T, Ketchem RR, Nguyen DN, Tolbert WD, Pierce BG, Atkinson B, Deming D, Sprague M, Asakawa A, Ferrer D, Dunn Y, Calvillo S, Yin R, Guest JD, Korber B, Mayer BT, Sato AH, Ouyang X, Foulke S, Habibzadeh P, Karimi M, Aslanabadi A, Hojabri M, Saadat S, Zareidoodeji R, Kędzior M, Pozharski E, Heredia A, Montefiori D, Ferrari G, Pazgier M, Lewis GK, Jardine JG, Lusso P, and DeVico A
- Abstract
Anti-HIV envelope broadly neutralizing antibodies (bnAbs) are alternatives to conventional antiretrovirals with the potential to prevent and treat infection, reduce latent reservoirs, and/or mediate a functional cure. Clinical trials with "first generation" bnAbs used alone or in combination show promising antiviral effects but also highlight that additional engineering of "enhanced" antibodies will be required for optimal clinical utility, while preserving or enhancing cGMP manufacturing capability. Here we report the engineering of an anti-CD4 binding-site (CD4bs) bnAb, N49P9.3, purified from the plasma of an HIV elite-neutralizer. Through a series of rational modifications we produced a variant that demonstrates: enhanced potency; superior antiviral activity in combination with other bnAbs; low polyreactivity; and longer circulating half-life. Additional engineering for manufacturing produced a final variant, eN49P9, with properties conducive to cGMP production. Overall, these efforts demonstrate the feasibility of developing enhanced anti-CD4bs bnAbs with greatly improved antiviral properties as well as potential translational value.
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- 2024
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24. Understanding antibody magnitude and durability following vaccination against SARS-CoV-2.
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Murphy QM, Lewis GK, Sajadi MM, Forde JE, and Ciupe SM
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- Humans, Vaccination, Spike Glycoprotein, Coronavirus immunology, Models, Immunological, Antibodies, Viral blood, Antibodies, Viral immunology, COVID-19 immunology, COVID-19 prevention & control, SARS-CoV-2 immunology, Immunoglobulin A blood, Immunoglobulin A immunology, Immunoglobulin G blood, Immunoglobulin G immunology, COVID-19 Vaccines immunology, COVID-19 Vaccines administration & dosage
- Abstract
Vaccination against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) results in transient antibody response against the spike protein. The individual immune status at the time of vaccination influences the response. Using mathematical models of antibody decay, we determined the dynamics of serum immunoglobulin G (IgG) and serum immunoglobulin A (IgA) over time. Data fitting to longitudinal IgG and IgA titers was used to quantify differences in antibody magnitude and antibody duration among infection-naïve and infection-positive vaccinees. We found that prior infections result in more durable serum IgG and serum IgA responses, with prior symptomatic infections resulting in the most durable serum IgG response and prior asymptomatic infections resulting in the most durable serum IgA response. These findings can guide vaccine boosting schedules., Competing Interests: Declaration of competing interest We declare no conflict of interest., (Copyright © 2024 Elsevier Inc. All rights reserved.)
- Published
- 2024
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25. Use of prophylactic ureteral stents in gynecologic surgery.
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Leon MG, Guha P, Lewis GK, Heckman MG, Siddiqui H, and Chen AH
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- Humans, Female, Middle Aged, Aged, Adult, Retrospective Studies, Aged, 80 and over, Adolescent, Young Adult, Stents adverse effects, Ureter surgery, Postoperative Complications prevention & control, Postoperative Complications epidemiology, Postoperative Complications etiology, Gynecologic Surgical Procedures adverse effects
- Abstract
Background: The aim of this study was to evaluate rate of complications with the use of prophylactic ureteral localization stents (PULSe) in gynecologic surgery. To compare the occurrence of complications according to the indication of surgery., Methods: This retrospective study included 1248 women who underwent 1275 different gynecologic surgeries with PULSe between 2007 and 2020. Data was collected regarding patient characteristics (age, sex, race, ethnicity, parity, previous pelvic surgery, creatinine), operative characteristics (trainee, guidewire use, indication) and complications in the first 30 days (ureteral injury, urinary tract complication, re-stenting, hydronephrosis, urinary tract infection (UTI), pyelonephritis, emergency room visit, re-admission)., Results: Median age was 57 years (range: 18-96 years), most women were Caucasian (88.9%), and had previous pelvic surgery (77.7%). Indication of surgery was benign for 459 (36.0%), female pelvic medicine and reconstructive surgery (FPMRS) for 545 (42.7%), and gynecologic oncology (gyn-onc) for 271 (21.3%). Disabling complications occurred rarely with 8 patients (0.6%) having a ≥III Clavien Dindo Grade (CDG), and only 1 (0.08%) ≥IV CDG. Statistically significant differences between benign, FPMRS, and gyn-onc groups were noted for re-stenting (0.9% vs. 0.0% vs. 1.1%, P=0.020), hydronephrosis (0.9% vs. 0.2% vs. 2.2%, P=0.014), UTI (4.6% vs. 9.4% vs. 7.0%, P=0.016), and re-admission (2.4% vs. 1.1% vs. 4.4%, P=0.014)., Conclusions: The incidence of 30-day CDG III and IV complications after PULSe placement is low. FPMRS patients had a higher rate of complicated UTI, however gyn- onc patients appear to be at overall higher risk of stent related complications when compared to surgeries for FPMRS or benign indications.
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- 2024
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26. Deficient Generation of Spike-Specific Long-Lived Plasma Cells in the Bone Marrow After Severe Acute Respiratory Syndrome Coronavirus 2 Infection.
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Tehrani ZR, Habibzadeh P, Flinko R, Chen H, Abbasi A, Yared JA, Ciupe SM, Lewis GK, and Sajadi MM
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- Humans, Male, Middle Aged, Female, Adult, Immunoglobulin G blood, Aged, COVID-19 immunology, Plasma Cells immunology, Spike Glycoprotein, Coronavirus immunology, Antibodies, Viral blood, SARS-CoV-2 immunology, Bone Marrow virology
- Abstract
Generation of a stable long-lived plasma cell (LLPC) population is the sine qua non of durable antibody responses after vaccination or infection. We studied 20 individuals with a prior coronavirus disease 2019 infection and characterized the antibody response using bone marrow aspiration and plasma samples. We noted deficient generation of spike-specific LLPCs in the bone marrow after severe acute respiratory syndrome coronavirus 2 infection. Furthermore, while the regression model explained 98% of the observed variance in anti-tetanus immunoglobulin G levels based on LLPC enzyme-linked immunospot assay, we were unable to fit the same model with anti-spike antibodies, again pointing to the lack of LLPC contribution to circulating anti-spike antibodies., Competing Interests: Potential conflicts of interest. All authors: No reported conflicts. All authors have submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Conflicts that the editors consider relevant to the content of the manuscript have been disclosed., (© The Author(s) 2024. Published by Oxford University Press on behalf of Infectious Diseases Society of America.)
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- 2024
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27. Identifying and Assessing Putative Allosteric Sites and Modulators for CXCR4 Predicted through Network Modeling and Site Identification by Ligand Competitive Saturation.
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Inan T, Flinko R, Lewis GK, MacKerell AD Jr, and Kurkcuoglu O
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- Ligands, Humans, Molecular Docking Simulation, Monte Carlo Method, Allosteric Regulation, Receptors, CXCR4 chemistry, Receptors, CXCR4 metabolism, Receptors, CXCR4 antagonists & inhibitors, Allosteric Site
- Abstract
The chemokine receptor CXCR4 is a critical target for the treatment of several cancer types and HIV-1 infections. While orthosteric and allosteric modulators have been developed targeting its extracellular or transmembrane regions, the intramembrane region of CXCR4 may also include allosteric binding sites suitable for the development of allosteric drugs. To investigate this, we apply the Gaussian Network Model (GNM) to the monomeric and dimeric forms of CXCR4 to identify residues essential for its local and global motions located in the hinge regions of the protein. Residue interaction network (RIN) analysis suggests hub residues that participate in allosteric communication throughout the receptor. Mutual residues from the network models reside in regions with a high capacity to alter receptor dynamics upon ligand binding. We then investigate the druggability of these potential allosteric regions using the site identification by ligand competitive saturation (SILCS) approach, revealing two putative allosteric sites on the monomer and three on the homodimer. Two screening campaigns with Glide and SILCS-Monte Carlo docking using FDA-approved drugs suggest 20 putative hit compounds including antifungal drugs, anticancer agents, HIV protease inhibitors, and antimalarial drugs. In vitro assays considering mAB 12G5 and CXCL12 demonstrate both positive and negative allosteric activities of these compounds, supporting our computational approach. However, in vivo functional assays based on the recruitment of β-arrestin to CXCR4 do not show significant agonism and antagonism at a single compound concentration. The present computational pipeline brings a new perspective to computer-aided drug design by combining conformational dynamics based on network analysis and cosolvent analysis based on the SILCS technology to identify putative allosteric binding sites using CXCR4 as a showcase.
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- 2024
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28. The association of endosalpingiosis with chronic pelvic pain.
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Ghaith S, Lewis GK, Craver EC, Li Z, Wasson MN, Burnett TL, and Carrubba AR
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- Female, Humans, Middle Aged, Retrospective Studies, Pelvic Pain etiology, Pelvic Pain complications, Endometriosis complications, Endometriosis epidemiology, Endometriosis surgery, Fallopian Tube Diseases complications, Fallopian Tube Diseases surgery, Fallopian Tube Diseases diagnosis, Chronic Pain etiology, Chronic Pain complications
- Abstract
Background: Endosalpingiosis is a pathologic diagnosis of ectopic epithelium resembling the fallopian tubes. It has been described with clinical characteristics that are similar to endometriosis. The primary objective is to determine if endosalpingiosis (ES) has a similar association with chronic pelvic pain when compared to endometriosis (EM)., Methods: This is a retrospective case-control analysis of patients with a histologic diagnosis of endosalpingiosis or endometriosis at three affiliated academic hospitals between 2000 and 2020. All ES patients were included, and 1:1 matching was attempted to obtain a comparable EM cohort. Demographic and clinical data were obtained, and statistical analysis was performed., Results: A total of 967 patients (515 ES and 452 EM) were included. ES patients were significantly older than EM patients (median age 52 vs. 48 years, P<0.001), but other demographic variables were similar. Fewer ES patients had baseline chronic pelvic pain than EM patients (25.3% vs. 47%, P<0.001), and patients with ES were less likely to undergo surgery for the primary indication of pelvic pain (16.1% vs. 35.4%, P<0.001). Pelvic pain as the surgical indication remained lower in the ES group in multivariable analysis (OR=0.49, P<0.001). There were similar rates of persistent postoperative pain between ES and EM groups (10.1% vs. 13.5%, P=0.109)., Conclusions: Although endosalpingiosis can be associated with chronic pelvic pain, the incidence of pain is significantly lower than in patients who have endometriosis. These findings suggest that ES is a unique condition that differs from EM. Further research including long-term follow-up and patient-reported outcomes is imperative.
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- 2024
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29. Caprini assessment utilization and impact on patient safety in gynecologic surgery.
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Lewis GK, Spaulding AC, Brennan E, Bakkum-Gamez JN, Dinh TA, Colibaseanu DT, Casler JD, and Edwards MA
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- Humans, Female, Risk Assessment methods, Postoperative Complications epidemiology, Postoperative Complications etiology, Postoperative Complications prevention & control, Retrospective Studies, Patient Safety, Hemorrhage, Gynecologic Surgical Procedures adverse effects, Risk Factors, Venous Thromboembolism epidemiology, Venous Thromboembolism etiology, Venous Thromboembolism prevention & control
- Abstract
Purpose: Postoperative venous thromboembolism (VTE) can potentially be associated with significant morbidity, mortality, and healthcare costs. The aim of this study was to determine the utilization of Caprini guideline indicated VTE in elective gynecologic surgery patients and its impact on postoperative VTE and bleeding complications., Methods: This was a retrospective cohort study of elective gynecologic surgical procedures performed between January 1, 2016, and May 31, 2021. Two study cohorts were generated: (1) those who received and (2) those who did not receive VTE prophylaxis based on Caprini score risk stratification. Outcome measures were then compared between the study cohorts and included the development of a VTE up to 90-days postoperatively. Secondary outcome measures included postoperative bleeding events., Results: A total of 5471 patients met inclusion criteria and the incidence of VTE up to 90 days postoperatively was 1.04%. Overall, 29.6% of gynecologic surgery patients received Caprini score-based guideline VTE prophylaxis. 39.2% of patients that met high-risk VTE criteria (Caprini > 5) received appropriate Caprini score-based prophylaxis. In multivariate regression analysis, the American Society of Anesthesiologists (ASA) score (OR 2.37, CI 1.27-4.45, p < 0.0001) and Caprini score (OR 1.13, CI 1.03-1.24, p = 0.008) predicted postoperatively VTE occurrence. Increasing Charlson comorbidity score (OR 1.39, CI 1.31-1.47, P < 0.001) ASA score (OR 1.36, CI 1.19-1.55, P < 0.001) and Caprini score (OR 1.10, CI 1.08-1.13, P < 0.001) were associated with increased odds of receiving appropriate inpatient VTE prophylaxis., Conclusion: While the overall incidence of VTE was low in this cohort, enhanced adherence to risk-based practice guidelines may provide more patient benefit than harm to postoperative gynecologic patients., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)
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- 2023
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30. Replacement of Antiretroviral Therapy with HIV Broadly Neutralizing Antibodies to Maximize the Effectiveness of Chemotherapy in HIV Patients with Lung Cancer.
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Atkinson B, Abassi A, Sajadi MM, Tehrani ZR, Le NM, Chen HH, Sausville E, DeVico AL, Lewis GK, Fan X, and Heredia A
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- Humans, Mice, Animals, Broadly Neutralizing Antibodies pharmacology, Broadly Neutralizing Antibodies therapeutic use, HIV Antibodies, Antibodies, Neutralizing, HIV Infections drug therapy, Carcinoma, Non-Small-Cell Lung drug therapy, Lung Neoplasms drug therapy, HIV-1 genetics
- Abstract
Non-small cell lung cancer (NSCLC) is the most fatal non-AIDS defining cancer in people living with HIV (PWH) on antiretroviral therapy (ART). Treatment of malignancies in PWH requires concomitant cancer therapy and ART, which can lead to potential drug-drug interactions (DDIs) and overlapping toxicities. In this study, we hypothesize that replacement of ART with HIV broadly neutralizing antibodies (bNAbs) during cancer chemotherapy (chemo) may maintain HIV suppression and tumor inhibition while minimizing DDIs and overlapping toxicities. We compared HIV suppression, tumor inhibition, and toxicity between conventional treatment (ART plus chemo) and a new modality (bNAbs plus chemo) in humanized mice. Humanized mice infected with HIV
YU2 and xenografted with human NSCLC A549 cells were treated with NSCLC chemo (cisplatin and gemcitabine) and first-line ART (dolutegravir, tenofovir disoproxil difumarate, and emtricitabine) or bNAbs (N49P9.6-FR and PGT 121) at human equivalent drug doses. We monitored plasma HIV RNA, tumor volume, and toxicities over five cycles of chemo. We found that chemo plus ART or bNAbs were equally effective at maintaining suppression of HIV viremia and tumor growth. Comparative analysis showed that mice on ART and chemo had significant reductions in body weight and significant increases in plasma creatinine concentrations compared with mice on bNAbs and chemo, which suggests that a combination of bNAbs and chemo produces less renal toxicity than an ART and chemo combination. These data suggest that bNAb therapy during concomitant chemo may be an improved treatment option over ART for PWH and NSCLC, and possibly other cancers, because bNAbs maintain HIV suppression while minimizing DDIs and toxicities.- Published
- 2023
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31. Two-photon fluorescence lifetime imaging microscopy of NADH metabolism in HIV-1 infected cells and tissues.
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Snyder GA, Kumar S, Lewis GK, and Ray K
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- Humans, NAD, Microscopy, Fluorescence, Homeostasis, HIV-1, HIV Seropositivity
- Abstract
Rapid detection of microbial-induced cellular changes during the course of an infection is critical to understanding pathogenesis and immunological homeostasis. In the last two decades, fluorescence imaging has received significant attention for its ability to help characterize microbial induced cellular and tissue changes in in vitro and in vivo settings. However, most of these methods rely on the covalent conjugation of large exogenous probes and detection methods based on intensity-based imaging. Here, we report a quantitative, intrinsic, label-free, and minimally invasive method based on two-photon fluorescence lifetime (FLT) imaging microscopy (2p-FLIM) for imaging 1,4-dihydro-nicotinamide adenine dinucleotide (NADH) metabolism of virally infected cells and tissue sections. To better understand virally induced cellular and tissue changes in metabolism we have used 2p-FLIM to study differences in NADH intensity and fluorescence lifetimes in HIV-1 infected cells and tissues. Differences in NADH fluorescence lifetimes are associated with cellular changes in metabolism and changes in cellular metabolism are associated with HIV-1 infection. NADH is a critical co-enzyme and redox regulator and an essential biomarker in the metabolic processes. Label-free 2p-FLIM application and detection of NADH fluorescence using viral infection systems are in their infancy. In this study, the application of the 2p-FLIM assay and quantitative analyses of HIV-1 infected cells and tissue sections reveal increased fluorescence lifetime and higher enzyme-bound NADH fraction suggesting oxidative phosphorylation (OxPhos) compared to uninfected cells and tissues. 2p-FLIM measurements improve signal to background, fluorescence specificity, provide spatial and temporal resolution of intracellular structures, and thus, are suitable for quantitative studies of cellular functions and tissue morphology. Furthermore, 2p-FLIM allows distinguishing free and bound populations of NADH by their different fluorescence lifetimes within single infected cells. Accordingly, NADH fluorescence measurements of individual single cells should provide necessary insight into the heterogeneity of metabolic activity of infected cells. Implementing 2p-FLIM to viral infection systems measuring NADH fluorescence at the single or subcellular level within a tissue can provide visual evidence, localization, and information in a real-time diagnostic or therapeutic metabolic workflow., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Snyder, Kumar, Lewis and Ray.)
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- 2023
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32. Synthetic Site-Specific Antibody-Ligand Conjugates Promote Asialoglycoprotein Receptor-Mediated Degradation of Extracellular Human PCSK9.
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Donahue TC, Ou C, Yang Q, Flinko R, Zhang X, Zong G, Lewis GK, and Wang LX
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- Humans, Asialoglycoprotein Receptor, Ligands, Asialoglycoproteins, Cetuximab, Cholesterol, LDL metabolism, Serine Endopeptidases metabolism, Proprotein Convertases metabolism
- Abstract
Targeted degradation using cell-specific lysosome targeting receptors is emerging as a new therapeutic strategy for the elimination of disease-associated proteins. The liver-specific human asialoglycoprotein receptor (ASGPR) is a particularly attractive lysosome targeting receptor leveraged for targeted protein degradation (TPD). However, the efficiency of different glycan ligands for ASGPR-mediated lysosomal delivery remains to be further characterized. In this study, we applied a chemoenzymatic Fc glycan remodeling method to construct an array of site-specific antibody-ligand conjugates carrying natural bi- and tri-antennary N -glycans as well as synthetic tri-GalNAc ligands. Alirocumab, an anti-PCSK9 (proprotein convertase subtilisin/kexin type 9) antibody, and cetuximab (an anti-EGFR antibody) were chosen to demonstrate the ASGPR-mediated degradation of extracellular and membrane-associated proteins, respectively. It was found that the nature of the glycan ligands and the length of the spacer in the conjugates are critical for the receptor binding and the receptor-mediated degradation of PCSK9, which blocks low-density lipoprotein receptor (LDLR) function and adversely affects clearance of low-density lipoprotein cholesterol. Interestingly, the antibody-tri-GalNAc conjugates showed a clear hook effect for its binding to ASGPR, while antibody conjugates carrying the natural N-glycans did not. Both the antibody-tri-antennary N-glycan conjugate and the antibody-tri-GalNAc conjugate could significantly decrease extracellular PCSK9, as shown in the cell-based assays. However, the tri-GalNAc conjugate showed a clear hook effect in the receptor-mediated degradation of PCSK9, while the antibody conjugate carrying the natural N-glycans did not. The cetuximab-tri-GalNAc conjugates also showed a similar hook effect on degradation of the membrane-associated protein, epidermal growth factor receptor (EGFR). These results suggest that the two types of ligands may involve a distinct mode of interactions in the receptor binding and target-degradation processes. Interestingly, the alirocumab-tri-GalNAc conjugate was also found to upregulate LDLR levels in comparison with the antibody alone. This study showcases the potential of the targeted degradation strategy against PCSK9 for reducing low-density lipoprotein cholesterol, a risk factor for heart disease and stroke.
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- 2023
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33. Development of an anti- Pseudomonas aeruginosa therapeutic monoclonal antibody WVDC-5244.
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Horspool AM, Sen-Kilic E, Malkowski AC, Breslow SL, Mateu-Borras M, Hudson MS, Nunley MA, Elliott S, Ray K, Snyder GA, Miller SJ, Kang J, Blackwood CB, Weaver KL, Witt WT, Huckaby AB, Pyles GM, Clark T, Al Qatarneh S, Lewis GK, Damron FH, and Barbier M
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- Mice, Animals, Pseudomonas aeruginosa, Antibodies, Monoclonal therapeutic use, Hybridomas metabolism, Complement System Proteins, Pneumonia microbiology, Pseudomonas Infections microbiology
- Abstract
The rise of antimicrobial-resistant bacterial infections is a crucial health concern in the 21st century. In particular, antibiotic-resistant Pseudomonas aeruginosa causes difficult-to-treat infections associated with high morbidity and mortality. Unfortunately, the number of effective therapeutic interventions against antimicrobial-resistant P. aeruginosa infections continues to decline. Therefore, discovery and development of alternative treatments are necessary. Here, we present pre-clinical efficacy studies on an anti- P. aeruginosa therapeutic monoclonal antibody. Using hybridoma technology, we generated a monoclonal antibody and characterized its binding to P. aeruginosa in vitro using ELISA and fluorescence correlation spectroscopy. We also characterized its function in vitro and in vivo against P. aeruginosa . The anti- P. aeruginosa antibody (WVDC-5244) bound P. aeruginosa clinical strains of various serotypes in vitro , even in the presence of alginate exopolysaccharide. In addition, WVDC-5244 induced opsonophagocytic killing of P. aeruginosa in vitro in J774.1 murine macrophage, and complement-mediated killing. In a mouse model of acute pneumonia, prophylactic administration of WVDC-5244 resulted in an improvement of clinical disease manifestations and reduction of P. aeruginosa burden in the respiratory tract compared to the control groups. This study provides promising pre-clinical efficacy data on a new monoclonal antibody with therapeutic potential for P. aeruginosa infections., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Horspool, Sen-Kilic, Malkowski, Breslow, Mateu-Borras, Hudson, Nunley, Elliott, Ray, Snyder, Miller, Kang, Blackwood, Weaver, Witt, Huckaby, Pyles, Clark, Al Qatarneh, Lewis, Damron and Barbier.)
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- 2023
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34. Maternal transfer of IgA and IgG SARS-CoV-2 specific antibodies transplacentally and via breast milk feeding.
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Sajadi MM, Shokatpour N, Purcell M, Tehrani ZR, Lankford A, Bathula A, Campbell JD, Hammershaimb EA, Deatrick KB, Bor C, Parsell DM, Dugan C, Levine AR, Ramelli SC, Chertow DS, Herr DL, Saharia KK, Lewis GK, and Grazioli A
- Subjects
- Infant, Female, Humans, Cross-Sectional Studies, SARS-CoV-2, Breast Feeding, Antibodies, Viral, Immunoglobulin A, Immunoglobulin G, Milk, Human, COVID-19 prevention & control
- Abstract
Background: Although there have been many studies on antibody responses to SARS-CoV-2 in breast milk, very few have looked at the fate of these in the infant, and whether they are delivered to immunologically relevant sites in infants., Methods: Mother/infant pairs (mothers who breast milk fed and who were SARS-CoV-2 vaccinated before or after delivery) were recruited for this cross-sectional study. Mother blood, mother breast milk, infant blood, infant nasal specimen, and infant stool was tested for IgA and IgG antibodies against SARS-CoV-2 spike trimer., Results: Thirty-one mother/infant pairs were recruited. Breast milk fed infants acquired systemic anti-spike IgG antibodies only if their mothers were vaccinated antepartum (100% Antepartum; 0% Postpartum; P<0.0001). Breast milk fed infants acquired mucosal anti-spike IgG antibodies (in the nose) only if their mothers were vaccinated antepartum (89% Antepartum; 0% Postpartum; P<0.0001). None of the infants in either group had anti-spike IgA in the blood. Surprisingly, 33% of the infants whose mothers were vaccinated antepartum had high titer anti-spike IgA in the nose (33% Antepartum; 0% Postpartum; P = 0.03). Half-life of maternally transferred plasma IgG antibodies in the Antepartum infant cohort was ~70 days., Conclusion: Vaccination antepartum followed by breast milk feeding appears to be the best way to provide systemic and local anti-SARS-CoV-2 antibodies for infants. The presence of high titer SARS-CoV-2-specific IgA in the nose of infants points to the potential importance of breast milk feeding early in life for maternal transfer of mucosal IgA antibodies. Expectant mothers should consider becoming vaccinated antepartum and consider breast milk feeding for optimal transfer of systemic and mucosal antibodies to their infants., Competing Interests: The authors have declared that no competing interests exist., (Copyright: This is an open access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.)
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- 2023
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35. Trigger point injections followed by immediate myofascial release in the treatment of pelvic floor tension myalgia.
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Lewis GK, Chen AH, Craver EC, Crook JE, and Carrubba AR
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- Humans, Female, Retrospective Studies, Pelvic Floor, Myofascial Release Therapy, Treatment Outcome, Myalgia therapy, Trigger Points
- Abstract
Purpose: Pelvic floor physical therapy (PFPT) is first-line therapy for treatment of pelvic floor tension myalgia (PFTM). Pelvic floor trigger point injections (PFTPI) are added if symptoms are refractive to conservative therapy or if patients experience a flare. The primary objective was to determine if a session of physical therapy with myofascial release immediately following PFTPI provides improved pain relief compared to trigger point injection alone., Methods: This was a retrospective cohort analysis of 87 female patients with PFTM who underwent PFTPI alone or PFTPI immediately followed by PFPT. Visual analog scale (VAS) pain scores were recorded pre-treatment and 2 weeks post-treatment. The primary outcome was the change in VAS between patients who received PFTPI alone and those who received PFTPI followed by myofascial release., Results: Of the 87 patients in this study, 22 received PFTPI alone and 65 patients received PFTPI followed by PFPT. The median pre-treatment VAS score was 8 for both groups. The median post-treatment score was 6 for the PFTPI only group and 4 for the PFTPI followed by PFPT group, showing a median change in VAS score of 2 and 4, respectively (p = 0.042). Seventy-seven percent of patients in the PFTPI followed by PFPT group had a VAS score improvement of 3 or more, while 45% of patients in the PFTPI only group had a VAS score improvement greater than 3 (p = 0.008)., Conclusion: PFTPI immediately followed by PFPT offered more improvement in pain for patients with PFTM. This may be due to greater tolerance of myofascial release immediately following injections., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)
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- 2023
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36. Erosion of a Gellhorn pessary into the bladder: a report of transvaginal removal and repair of vesicovaginal fistula.
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Lewis GK, Leon MG, and Chen AH
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- Female, Humans, Pessaries adverse effects, Urinary Bladder surgery, Vesicovaginal Fistula etiology, Vesicovaginal Fistula surgery
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- 2023
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37. Evidence of variable human Fcγ receptor-Fc affinities across differentially-complexed IgG.
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Crowley AR, Mehlenbacher MR, Sajadi MM, DeVico AL, Lewis GK, and Ackerman ME
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- Humans, Protein Binding, Immunoglobulin Fc Fragments chemistry, Cell Membrane metabolism, Receptors, IgG, Immunoglobulin G chemistry
- Abstract
Antibody-mediated effector functions are widely considered to unfold according to an associative model of IgG-Fcγ receptor (FcγR) interactions. The associative model presupposes that Fc receptors cannot discriminate antigen-bound IgG from free IgG in solution and have equivalent affinities for each. Therefore, the clustering of Fcγ receptors (FcγR) in the cell membrane, cross-activation of intracellular signaling domains, and the formation of the immune synapse are all the result of avid interactions between the Fc region of IgG and FcγRs that collectively overcome the individually weak, transient interactions between binding partners. Antibody allostery, specifically conformational allostery, is a competing model in which antigen-bound antibody molecules undergo a physical rearrangement that causes them to stand out from the background of free IgG by virtue of greater FcγR affinity. Various evidence exists in support of this model of antibody allostery, but it remains controversial. We report observations from multiplexed, label-free kinetic experiments in which the affinity values of FcγR were characterized for covalently immobilized, captured, and antigen-bound IgG. Across the strategies tested, receptors had greater affinity for the antigen-bound mode of IgG presentation. This phenomenon was observed across multiple FcγRs and generalized to multiple antigens, antibody specificities, and subclasses. Furthermore, the thermodynamic signatures of FcγR binding to free or immune-complexed IgG in solution differed when measured by an orthogonal label-free method, but the failure to recapitulate the trend in overall affinity leaves open questions as to what additional factors may be at play.
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- 2023
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38. OnabotulinumtoxinA Injections for the Treatment of Myofascial Pelvic Pain: 12-Year Experience at a Tertiary Care Academic Center.
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Lewis GK, Carrubba AR, Stanton AP, Craver EC, Li Z, and Chen AH
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- Female, Humans, Pelvic Pain drug therapy, Pelvic Pain etiology, Retrospective Studies, Tertiary Healthcare, Nerve Block, Injections, Intramuscular, Treatment Outcome, Botulinum Toxins, Type A administration & dosage, Botulinum Toxins, Type A adverse effects, Botulinum Toxins, Type A therapeutic use, Pudendal Nerve, Myofascial Pain Syndromes drug therapy
- Abstract
Objective: The aim of this study was to highlight the safety of OnabotulinumtoxinA (BTA) injections, with or without concurrent pudendal nerve block, in treating women with myofascial pelvic pain (MFPP)., Design: This was a retrospective cohort study., Setting: The review was conducted in a tertiary care academic center. Participants/Materials: We conducted a chart review of patients who were diagnosed with MFPP and treated with BTA with or without pudendal nerve block between January 2010 and February 2022., Methods: BTA was injected transvaginally into the pelvic floor muscle group. The primary outcomes were adverse events after BTA injections, and the secondary outcome was the effect of concomitant pudendal nerve block at the time of BTA injections., Results: The cohort included 182 patients; 103 (56.6%) received BTA injections with pudendal nerve block, and 79 (43.4%) received BTA alone. There were no significant demographic differences between the two groups. Post-treatment complications of BTA administration included worsening of pelvic pain (11.5%), constipation (6.6%), urinary tract infection (2.7%), urinary retention (3.8%), and fecal incontinence (2.7%). No statistical difference was noted in the number of phone calls, patient-initiated electronic messages, emergency room visits, or clinic visits for both groups within 30 days post-treatment. The mean number of total injections was 1.6 in the BTA-only group and 1.7 in the BTA with pudendal block group (p = 0.421). Median time to re-intervention with a second BTA injection was 6.0 months; 5.6 months in the BTA with pudendal block group; and 6.8 months in the BTA-only group, p = 0.46. There were 63 re-intervention events after BTA injections., Limitations: Limitations of our study include the retrospective design making it vulnerable to missing or incomplete data available for review., Conclusion: OnabotulinumtoxinA is beneficial in treating women with MFPP; with a duration of therapeutic effect of approximately 6 months. The use of a concurrent pudendal nerve block did not impact clinical outcomes., (© 2022 S. Karger AG, Basel.)
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- 2023
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39. The association of endosalpingiosis with gynecologic malignancy.
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Lewis GK, Ghaith S, Craver EC, Li Z, Wasson MN, Burnett TL, and Carrubba AR
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- Fallopian Tubes pathology, Female, Humans, Middle Aged, Retrospective Studies, Endometriosis complications, Endometriosis diagnosis, Endometriosis epidemiology, Fallopian Tube Diseases diagnosis, Fallopian Tube Diseases epidemiology, Genital Neoplasms, Female complications, Genital Neoplasms, Female epidemiology, Urogenital Diseases
- Abstract
Objective: Endosalpingiosis is a poorly understood condition of ectopic epithelium resembling the fallopian tubes. It has been described as an incidental pathology finding, a disease similar to endometriosis, and in association with malignancy. The objective of this study is to determine if endosalpingiosis (ES) has an increased association with gynecologic malignancy when compared to endometriosis (EM)., Methods: This is a retrospective case-control analysis of patients with a histologic diagnosis of endosalpingiosis or endometriosis at three affiliated academic hospitals between 2000 and 2020. All ES patients were included, and 1:1 matching was attempted to obtain a comparable cohort of EM patients. Demographic and clinical data were obtained, and statistical analysis was performed., Results: A total of 967 patients (515 ES and 452 EM) were included. ES patients were significantly older than EM patients (median age 52 vs 48 years, p < 0.001). The ES group had significantly more cancer diagnoses at surgery than the EM group (40.1% vs 18.1%, p < 0.001); this difference persisted in a sub-analysis excluding patients with known or suspected malignancy (20.9% vs 5.6%, p < 0.001). ES patients had lower overall survival (10-year freedom from death: 77.0% vs 90.5%, p < 0.001). After adjusting for confounders, multivariable analysis showed that ES patients had increased cancer diagnosed at surgery (OR = 2.48, p < 0.001) and greater risk of death (OR = 1.69, p = 0.017)., Conclusions: Endosalpingiosis was found concurrently with malignancy in 40% of cases, and this effect was preserved in multi-variable and sub-group analyses. Further research consisting of longer follow-up and exploration of molecular relationships between ES and cancer are forthcoming., Competing Interests: Declaration of Competing Interest The authors of this study have no conflicts of interest., (Copyright © 2022 Elsevier Inc. All rights reserved.)
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- 2022
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40. Decoding human-macaque interspecies differences in Fc-effector functions: The structural basis for CD16-dependent effector function in Rhesus macaques.
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Tolbert WD, Gohain N, Kremer PG, Hederman AP, Nguyen DN, Van V, Sherburn R, Lewis GK, Finzi A, Pollara J, Ackerman ME, Barb AW, and Pazgier M
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- Animals, Humans, Immunoglobulin Fc Fragments immunology, Macaca mulatta, Receptors, IgG immunology, Immunoglobulin G, Polysaccharides metabolism
- Abstract
Fc mediated effector functions of antibodies play important roles in immunotherapies and vaccine efficacy but assessing those functions in animal models can be challenging due to species differences. Rhesus macaques, Macaca mulatta (Mm) share approximately 93% sequence identity with humans but display important differences in their adaptive immune system that complicates their use in validating therapeutics and vaccines that rely on Fc effector functions. In contrast to humans, macaques only have one low affinity FcγRIII receptor, CD16, which shares a polymorphism at position 158 with human FcγRIIIa with Ile
158 and Val158 variants. Here we describe structure-function relationships of the Ile/Val158 polymorphism in Mm FcγRIII. Our data indicate that the affinity of the allelic variants of Mm FcγRIII for the macaque IgG subclasses vary greatly with changes in glycan composition both on the Fc and the receptor. However, unlike the human Phe/Val158 polymorphism in FcγRIIIa, the higher affinity variant corresponds to the larger, more hydrophobic side chain, Ile, even though it is not directly involved in the binding interface. Instead, this side chain appears to modulate glycan-glycan interactions at the Fc/FcγRIII interface. Furthermore, changes in glycan composition on the receptor have a greater effect for the Val158 variant such that with oligomannose type glycans and with glycans only on Asn45 and Asn162 , Val158 becomes the variant with higher affinity to Fc. These results have implications not only for the better interpretation of nonhuman primate studies but also for studies performed with human effector cells carrying different FcγRIIIa alleles., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Tolbert, Gohain, Kremer, Hederman, Nguyen, Van, Sherburn, Lewis, Finzi, Pollara, Ackerman, Barb and Pazgier.)- Published
- 2022
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41. Impact of adjuvants on the biophysical and functional characteristics of HIV vaccine-elicited antibodies in humans.
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Xu S, Carpenter MC, Spreng RL, Neidich SD, Sarkar S, Tenney D, Goodman D, Sawant S, Jha S, Dunn B, Juliana McElrath M, Bekker V, Mudrak SV, Flinko R, Lewis GK, Ferrari G, Tomaras GD, Shen X, and Ackerman ME
- Abstract
Adjuvants can alter the magnitude, characteristics, and persistence of the humoral response to protein vaccination. HIV vaccination might benefit from tailored adjuvant choice as raising a durable and protective response to vaccination has been exceptionally challenging. Analysis of trials of partially effective HIV vaccines have identified features of the immune response that correlate with decreased risk, including high titers of V1V2-binding IgG and IgG3 responses with low titers of V1V2-binding IgA responses and enhanced Fc effector functions, notably antibody-dependent cellular cytotoxicity (ADCC) and antibody-dependent cellular phagocytosis (ADCP). However, there has been limited opportunity to compare the effect of different adjuvants on these activities in humans. Here, samples from the AVEG015 study, a phase 1 trial in which participants (n = 112) were immunized with gp120
SF-2 and one of six different adjuvants or combinations thereof were assessed for antibody titer, biophysical features, and diverse effector functions. Three adjuvants, MF59 + MTP-PE, SAF/2, and SAF/2 + MDP, increased the peak magnitude and durability of antigen-specific IgG3, IgA, FcγR-binding responses and ADCP activity, as compared to alum. While multiple adjuvants increased the titer of IgG, IgG3, and IgA responses, none consistently altered the balance of IgG to IgA or IgG3 to IgA. Linear regression analysis identified biophysical features including gp120-specific IgG and FcγR-binding responses that could predict functional activity, and network analysis identified coordinated aspects of the humoral response. These analyses reveal the ability of adjuvants to drive the character and function of the humoral response despite limitations of small sample size and immune variability in this human clinical trial., (© 2022. The Author(s).)- Published
- 2022
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42. Clear cell adenocarcinoma arising from anterior abdominal wall cesarean section scar endometriosis treated with excision and the addition of Trastuzumab for adjuvant chemotherapy: A case report.
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Lewis GK, Gajarawala SN, Robinson KE, Chen AH, and Robertson MW
- Abstract
Abdominal wall endometriosis with subsequent transformation to clear cell carcinoma is quite rare. The pathogenesis and pattern of this transformation is not well known; hence evaluation and management guidelines are not well established. We highlight a case of clear cell adenocarcinoma arising from the anterior abdominal wall in a previous cesarean section scar treated with excision and the unique addition of Trastuzumab for adjuvant chemotherapy., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2022 The Authors.)
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- 2022
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43. Structure and Fc-Effector Function of Rhesusized Variants of Human Anti-HIV-1 IgG1s.
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Tolbert WD, Nguyen DN, Tuyishime M, Crowley AR, Chen Y, Jha S, Goodman D, Bekker V, Mudrak SV, DeVico AL, Lewis GK, Theis JF, Pinter A, Moody MA, Easterhoff D, Wiehe K, Pollara J, Saunders KO, Tomaras GD, Ackerman M, Ferrari G, and Pazgier M
- Subjects
- Humans, Antibodies, Monoclonal chemistry, Antibodies, Monoclonal immunology, HIV Antibodies chemistry, HIV Antibodies immunology, HIV-1 immunology, Immunoglobulin G chemistry, Immunoglobulin G immunology
- Abstract
Passive transfer of monoclonal antibodies (mAbs) of human origin into Non-Human Primates (NHPs), especially those which function predominantly by a Fc-effector mechanism, requires an a priori preparation step, in which the human mAb is reengineered to an equivalent NHP IgG subclass. This can be achieved by changing both the Fc and Fab sequence while simultaneously maintaining the epitope specificity of the parent antibody. This Ab reengineering process, referred to as rhesusization, can be challenging because the simple grafting of the complementarity determining regions (CDRs) into an NHP IgG subclass may impact the functionality of the mAb. Here we describe the successful rhesusization of a set of human mAbs targeting HIV-1 envelope (Env) epitopes involved in potent Fc-effector function against the virus. This set includes a mAb targeting a linear gp120 V1V2 epitope isolated from a RV144 vaccinee, a gp120 conformational epitope within the Cluster A region isolated from a RV305 vaccinated individual, and a linear gp41 epitope within the immunodominant Cys-loop region commonly targeted by most HIV-1 infected individuals. Structural analyses confirm that the rhesusized variants bind their respective Env antigens with almost identical specificity preserving epitope footprints and most antigen-Fab atomic contacts with constant regions folded as in control RM IgG1s. In addition, functional analyses confirm preservation of the Fc effector function of the rhesusized mAbs including the ability to mediate Antibody Dependent Cell-mediated Cytotoxicity (ADCC) and antibody dependent cellular phagocytosis by monocytes (ADCP) and neutrophils (ADNP) with potencies comparable to native macaque antibodies of similar specificity. While the antibodies chosen here are relevant for the examination of the correlates of protection in HIV-1 vaccine trials, the methods used are generally applicable to antibodies for other purposes., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Tolbert, Nguyen, Tuyishime, Crowley, Chen, Jha, Goodman, Bekker, Mudrak, DeVico, Lewis, Theis, Pinter, Moody, Easterhoff, Wiehe, Pollara, Saunders, Tomaras, Ackerman, Ferrari and Pazgier.)
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- 2022
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44. Diverse antiviral IgG effector activities are predicted by unique biophysical antibody features.
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Cheng HD, Dowell KG, Bailey-Kellogg C, Goods BA, Love JC, Ferrari G, Alter G, Gach J, Forthal DN, Lewis GK, Greene K, Gao H, Montefiori DC, and Ackerman ME
- Subjects
- HIV Infections immunology, Humans, HIV Antibodies chemistry, HIV Antibodies immunology, HIV Infections virology, HIV-1 immunology, Immunoglobulin Fc Fragments chemistry, Immunoglobulin Fc Fragments immunology, Immunoglobulin G chemistry, Immunoglobulin G immunology
- Abstract
Background: The critical role of antibody Fc-mediated effector functions in immune defense has been widely reported in various viral infections. These effector functions confer cellular responses through engagement with innate immune cells. The precise mechanism(s) by which immunoglobulin G (IgG) Fc domain and cognate receptors may afford protection are poorly understood, however, in the context of HIV/SHIV infections. Many different in vitro assays have been developed and utilized to measure effector functions, but the extent to which these assays capture distinct antibody activities has not been fully elucidated., Results: In this study, six Fc-mediated effector function assays and two biophysical antibody profiling assays were performed on a common set of samples from HIV-1 infected and vaccinated subjects. Biophysical antibody profiles supported robust prediction of diverse IgG effector functions across distinct Fc-mediated effector function assays. While a number of assays showed correlated activities, supervised machine learning models indicated unique antibody features as primary contributing factors to the associated effector functions. Additional experiments established the mechanistic relevance of relationships discovered using this unbiased approach., Conclusions: In sum, this study provides better resolution on the diversity and complexity of effector function assays, offering a clearer perspective into this family of antibody mechanisms of action to inform future HIV-1 treatment and vaccination strategies., (© 2021. The Author(s).)
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- 2021
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45. Marjolin's Ulcer: Mesh-Related Vaginal Cutaneous Fistula With Superimposed Osteomyelitis and Neoplastic Transformation.
- Author
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Gajarawala SN, Pelkowski JN, Pettit PD, and Lewis GK
- Abstract
Marjolin's ulcer is a rare, often aggressive squamous cell malignancy identified in previously injured areas or those affected by chronic inflammation. It often develops in deep wounds that are slow to heal or allowed to heal by secondary intention. Few reports and small case series about Marjolin's ulcer have been published. We present a unique case with well-differentiated keratinized squamous cell carcinoma arising from a mesh-related vaginocutaneous fistula with superimposed osteomyelitis. The risk of cancerous transformation leading to Marjolin's ulcer in non-healing traumatic wounds is 8.1% and 2.6% in a fistula associated with purulent-inflammatory bone diseases. Approximately 1.7% of chronic cutaneous ulcers undergo neoplastic transformation, with a disposition to squamous cell carcinoma. Women experiencing mesh complications may require multiple procedures to address these issues and, therefore, should have them addressed in a timely manner to allow for the best patient outcome. Treatment optimization on a whole should incorporate the goals outlined by the American Urogynecologic Society and the International Urogynecological Association. These include the use of relevant evidence to help guide the management of mesh complications as well as identifying the gaps in currently available evidence, developing a treatment algorithm to be used for shared decision making, and identifying provider and healthcare facility characteristics that may optimize treatment outcomes specific to mesh complications., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2021, Gajarawala et al.)
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- 2021
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46. Safety and immunogenicity of an HIV-1 gp120-CD4 chimeric subunit vaccine in a phase 1a randomized controlled trial.
- Author
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Chua JV, Davis C, Husson JS, Nelson A, Prado I, Flinko R, Lam KWJ, Mutumbi L, Mayer BT, Dong D, Fulp W, Mahoney C, Gerber M, Gottardo R, Gilliam BL, Greene K, Gao H, Yates N, Ferrari G, Tomaras G, Montefiori D, Schwartz JA, Fouts T, DeVico AL, Lewis GK, Gallo RC, and Sajadi MM
- Subjects
- AIDS Vaccines adverse effects, Adult, Animals, CD4 Antigens, HIV Antibodies, HIV Envelope Protein gp120, HIV-1, Humans, Vaccines, Subunit adverse effects, Vaccines, Subunit immunology, AIDS Vaccines immunology, HIV Infections prevention & control, Immunogenicity, Vaccine
- Abstract
A major challenge for HIV vaccine development is to raise anti-envelope antibodies capable of recognizing and neutralizing diverse strains of HIV-1. Accordingly, a full length single chain (FLSC) of gp120-CD4 chimeric vaccine construct was designed to present a highly conserved CD4-induced (CD4i) HIV-1 envelope structure that elicits cross-reactive anti-envelope humoral responses and protective immunity in animal models of HIV infection. IHV01 is the FLSC formulated in aluminum phosphate adjuvant. We enrolled 65 healthy adult volunteers in this first-in-human phase 1a randomized, double-blind, placebo-controlled study with three dose-escalating cohorts (75 µg, 150 µg, and 300 µg doses). Intramuscular injections were given on weeks 0, 4, 8, and 24. Participants were followed for an additional 24 weeks after the last immunization. The overall incidence of adverse events (AEs) was not significantly different between vaccinees and controls. The majority (89%) of vaccine-related AE were mild. The most common vaccine-related adverse event was injection site pain. There were no vaccine-related serious AE, discontinuation due to AE, intercurrent HIV infection, or significant decreases in CD4 count. By the final vaccination, all vaccine recipients developed antibodies against IHV01 and demonstrated anti-CD4i epitope antibodies. The elicited antibodies reacted with CD4 non-liganded Env antigens from diverse HIV-1 strains. Antibody-dependent cell-mediated cytotoxicity against heterologous infected cells or gp120 bound to CD4+ cells was evident in all cohorts as were anti-gp120 T-cell responses. IHV01 vaccine was safe, well tolerated, and immunogenic at all doses tested. The vaccine raised broadly reactive humoral responses against conserved CD4i epitopes on gp120 that mediates antiviral functions., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 The Author(s). Published by Elsevier Ltd.. All rights reserved.)
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- 2021
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47. Erratum for Tolbert et al., "Recognition Patterns of the C1/C2 Epitopes Involved in Fc-Mediated Response in HIV-1 Natural Infection and the RV114 Vaccine Trial".
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Tolbert WD, Van V, Sherburn R, Tuyishime M, Yan F, Nguyen DN, Stanfield-Oakley S, Easterhoff D, Bonsignori M, Haynes BF, Moody MA, Ray K, Ferrari G, Lewis GK, and Pazgier M
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- 2021
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48. Performance of nucleocapsid and spike-based SARS-CoV-2 serologic assays.
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Rikhtegaran Tehrani Z, Saadat S, Saleh E, Ouyang X, Constantine N, DeVico AL, Harris AD, Lewis GK, Kottilil S, and Sajadi MM
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- Adult, Aged, Aged, 80 and over, Area Under Curve, Betacoronavirus isolation & purification, COVID-19, Coronavirus Infections virology, Female, Humans, Immunoglobulin A blood, Immunoglobulin G blood, Immunoglobulin M blood, Male, Middle Aged, Pandemics, Pneumonia, Viral virology, ROC Curve, Reproducibility of Results, SARS-CoV-2, Antibodies, Viral blood, Betacoronavirus metabolism, Coronavirus Infections diagnosis, Immunoassay methods, Nucleocapsid immunology, Pneumonia, Viral diagnosis, Spike Glycoprotein, Coronavirus immunology
- Abstract
There is an urgent need for an accurate antibody test for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We have developed 3 ELISA methods, trimer spike IgA, trimer spike IgG, and nucleocapsid IgG, for detecting anti-SARS-CoV-2 antibodies. We evaluated their performance along with four commercial ELISAs, EDI™ Novel Coronavirus COVID-19 ELISA IgG and IgM, Euroimmun Anti-SARS-CoV-2 ELISA IgG and IgA, and one lateral flow assay, DPP® COVID-19 IgM/IgG System (Chembio). Both sensitivity and specificity were evaluated and the probable causes of false-positive reactions were determined. The assays were evaluated using 300 pre-epidemic samples and 100 PCR-confirmed COVID-19 samples. The sensitivities and specificities of the assays were as follows: 90%/100% (in-house trimer spike IgA), 90%/99.3% (in-house trimer spike IgG), 89%/98.3% (in-house nucleocapsid IgG), 73.7%/100% (EDI nucleocapsid IgM), 84.5%/95.1% (EDI nucleocapsid IgG), 95%/93.7% (Euroimmun S1 IgA), 82.8%/99.7% (Euroimmun S1 IgG), 82.0%/91.7% (Chembio nucleocapsid IgM), 92%/93.3% (Chembio nucleocapsid IgG). The presumed causes of false positive results from pre-epidemic samples in commercial and in-house assays were mixed. In some cases, assays lacked reproducibility. In other cases, reactivity was abrogated by competitive inhibition (spiking the sample with the same antigen that was used for coating ELISAs prior to performing the assay), suggesting positive reaction could be attributed to the presence of antibodies against these antigens. In other cases, reactivity was consistently detected but not abrogated by the spiking, suggesting positive reaction was not attributed to the presence of antibodies against these antigens. Overall, there was wide variability in assay performance using our samples, with in-house tests exhibiting the highest combined sensitivity and specificity. The causes of "false positivity" in pre-epidemic samples may be due to plasma antibodies apparently reacting with the corresponding antigen, or spurious reactivity may be directed against non-specific components in the assay system. Identification of these targets will be essential to improving assay performance., Competing Interests: The authors have declared that no competing interests exist.
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- 2020
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49. Specificity and Performance of Nucleocapsid and Spike-based SARS-CoV-2 Serologic Assays.
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Tehrani ZR, Saadat S, Saleh E, Ouyang X, Constantine N, DeVico AL, Harris AD, Lewis GK, Kottilil S, and Sajadi MM
- Abstract
There is an urgent need for an accurate antibody test for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In this paper, we have developed 3 ELISA methods, trimer spike IgA, trimer spike IgG, and nucleocapsid IgG, for detecting anti-SARS-CoV-2 antibodies. We evaluated their performance in comparison with four commercial ELISAs, EDI™ Novel Coronavirus COVID-19 ELISA IgG and IgM, Euroimmun Anti-SARS-CoV-2 ELISA IgG and IgA, and one lateral flow assay, DPP® COVID-19 IgM/IgG System (Chembio). Both sensitivity and specificity were evaluated and the causes of false-positive reactions were determined. The assays were compared using 300 pre-epidemic samples and 100 PCR-confirmed COVID-19 samples. The sensitivities and specificities of the assays were as follows: 90%/100% (in-house trimer spike IgA), 90%/99.3% (in-house trimer spike IgG), 89%/98.3% (in-house nucleocapsid IgG), 73.7%/100% (EDI nucleocapsid IgM), 84.5%/95.1% (EDI nucleocapsid IgG), 95%/93.7% (Euroimmun S1 IgA), 82.8%/99.7% (Euroimmun S1 IgG), 82.0%/91.7% (Chembio nucleocapsid IgM), 92%/93.3% (Chembio nucleocapsid IgG). The presumed causes of positive signals from pre-epidemic samples in commercial and in-house assays were mixed. In some cases, positivity varied with assay repetition. In other cases, reactivity was abrogated by competitive inhibition (spiking the sample with analyte prior to performing the assay). In other cases, reactivity was consistently detected but not abrogated by analyte spiking. Overall, there was wide variability in assay performance using our samples, with in-house tests exhibiting the highest combined sensitivity and specificity. The causes of "false positivity" in pre-epidemic samples may be due to plasma antibodies apparently reacting with the analyte, or spurious reactivity may be directed against non-specific components in the assay system. Identification of these targets will be essential to improving assay performance.
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- 2020
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50. Defining rules governing recognition and Fc-mediated effector functions to the HIV-1 co-receptor binding site.
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Tolbert WD, Sherburn R, Gohain N, Ding S, Flinko R, Orlandi C, Ray K, Finzi A, Lewis GK, and Pazgier M
- Subjects
- Antibodies, Monoclonal metabolism, Antibodies, Viral metabolism, Humans, Receptors, HIV metabolism, HIV-1 physiology, Receptors, HIV genetics
- Abstract
Background: The binding of HIV-1 Envelope glycoproteins (Env) to host receptor CD4 exposes vulnerable conserved epitopes within the co-receptor binding site (CoRBS) which are required for the engagement of either CCR5 or CXCR4 co-receptor to allow HIV-1 entry. Antibodies against this region have been implicated in the protection against HIV acquisition in non-human primate (NHP) challenge studies and found to act synergistically with antibodies of other specificities to deliver effective Fc-mediated effector function against HIV-1-infected cells. Here, we describe the structure and function of N12-i2, an antibody isolated from an HIV-1-infected individual, and show how the unique structural features of this antibody allow for its effective Env recognition and Fc-mediated effector function., Results: N12-i2 binds within the CoRBS utilizing two adjacent sulfo-tyrosines (TYS) for binding, one of which binds to a previously unknown TYS binding pocket formed by gp120 residues of high sequence conservation among HIV-1 strains. Structural alignment with gp120 in complex with the co-receptor CCR5 indicates that the new pocket corresponds to TYS at position 15 of CCR5. In addition, structure-function analysis of N12-i2 and other CoRBS-specific antibodies indicates a link between modes of antibody binding within the CoRBS and Fc-mediated effector activities. The efficiency of antibody-dependent cellular cytotoxicity (ADCC) correlated with both the level of antibody binding and the mode of antibody attachment to the epitope region, specifically with the way the Fc region was oriented relative to the target cell surface. Antibodies with poor Fc access mediated the poorest ADCC whereas those with their Fc region readily accessible for interaction with effector cells mediated the most potent ADCC., Conclusion: Our data identify a previously unknown binding site for TYS within the assembled CoRBS of the HIV-1 virus. In addition, our combined structural-modeling-functional analyses provide new insights into mechanisms of Fc-effector function of antibodies against HIV-1, in particular, how antibody binding to Env antigen affects the efficiency of ADCC response.
- Published
- 2020
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