47 results on '"Frendéus B"'
Search Results
2. A platform for phenotypic discovery of therapeutic antibodies and targets applied on Chronic Lymphocytic Leukemia
- Author
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Ljungars, A., Mårtensson, L., Mattsson, J., Kovacek, M., Sundberg, A., Tornberg, U-C., Jansson, B., Persson, N., Emruli, V. Kuci, Ek, S., Jerkeman, M., Hansson, M., Juliusson, G., Ohlin, M., Frendéus, B., Teige, I., and Mattsson, M.
- Published
- 2018
- Full Text
- View/download PDF
3. Toll-Like Receptor Signaling and Chemokine Receptor Expression Influence the Severity of Urinary Tract Infection
- Author
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Svanborg, C., Frendéus, B., Godaly, G., Hang, L., Hedlund, M., and Wachtler, C.
- Published
- 2001
4. FcγRIIb expression is decreased on naive and marginal Zone-Like B Cells from females with multiple sclerosis
- Author
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Trend, S., Leffler, J., Teige, I., Frendéus, B., Kermode, A.G., French, M.A., Hart, P.H., Trend, S., Leffler, J., Teige, I., Frendéus, B., Kermode, A.G., French, M.A., and Hart, P.H.
- Abstract
B cells are critical to the development of multiple sclerosis (MS), but the mechanisms by which they contribute to the disease are poorly defined. We hypothesised that the expression of CD32b (FcγRIIb), a receptor for the Fc region of IgG with inhibitory activities in B cells, is lower on B cell subsets from people with clinically isolated syndrome (CIS) or MS. CD32b expression was highest on post-naive IgM+ B cell subsets in healthy controls. For females with MS or CIS, significantly lower CD32b expression was identified on IgM+ B cell subsets, including naive and IgMhi MZ-like B cells, when compared with control females. Lower CD32b expression on these B cell subsets was associated with detectable anti-Epstein Barr Virus viral capsid antigen IgM antibodies, and higher serum levels of B cell activating factor. To investigate the effects of lower CD32b expression, B cells were polyclonally activated in the presence of IgG immune complexes, with or without a CD32b blocking antibody, and the expression of TNF and IL-10 in B cell subsets was assessed. The reduction of TNF but not IL-10 expression in controls mediated by IgG immune complexes was reversed by CD32b blockade in naive and IgMhi MZ-like B cells only. However, no consequence of lower CD32b expression on these cells from females with CIS or MS was detected. Our findings highlight a potential role for naive and marginal zone-like B cells in the immunopathogenesis of MS in females, which requires further investigation.
- Published
- 2021
5. Evaluating anti-CD32b F(ab) conformation using molecular dynamics and small-angle X-ray scattering
- Author
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Sutton, E.J., Bradshaw, R.T., Orr, C.M., Frendéus, B., Larsson, G., Teige, I., Cragg, M.S., Tews, I., and Essex, J.W.
- Abstract
Complementary strategies of small-angle x-ray scattering (SAXS) and crystallographic analysis are often used to determine atomistic three-dimensional models of macromolecules and their variability in solution. This combination of techniques is particularly valuable when applied to macromolecular complexes to detect changes within the individual binding partners. Here, we determine the x-ray crystallographic structure of a F(ab) fragment in complex with CD32b, the only inhibitory Fc-γ receptor in humans, and compare the structure of the F(ab) from the crystal complex to SAXS data for the F(ab) alone in solution. We investigate changes in F(ab) structure by predicting theoretical scattering profiles for atomistic structures extracted from molecular dynamics (MD) simulations of the F(ab) and assessing the agreement of these structures to our experimental SAXS data. Through principal component analysis, we are able to extract principal motions observed during the MD trajectory and evaluate the influence of these motions on the agreement of structures to the F(ab) SAXS data. Changes in the F(ab) elbow angle were found to be important to reach agreement with the experimental data; however, further discrepancies were apparent between our F(ab) structure from the crystal complex and SAXS data. By analyzing multiple MD structures observed in similar regions of the principal component analysis, we were able to pinpoint these discrepancies to a specific loop region in the F(ab) heavy chain. This method, therefore, not only allows determination of global changes but also allows identification of localized motions important for determining the agreement between atomistic structures and SAXS data. In this particular case, the findings allowed us to discount the hypothesis that structural changes were induced upon complex formation, a significant find informing the drug development process. The methodology described here is generally applicable to deconvolute global and local changes of macromolecular structures and is well suited to other systems.
- Published
- 2018
6. PHASE 1/2A CLINICAL TRIALS OF BI-1206, A MONOCLONAL ANTIBODY TO FCΓRIIB, ADMINISTERED AS A SINGLE AGENT OR IN COMBINATION WITH RITUXIMAB IN SUBJECTS WITH B-CELL MALIGNANCIES
- Author
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Karlsson, I., primary, Traub, S., additional, Järås, K., additional, Edwards, D., additional, Gramming, E., additional, Lindell Andersson, M., additional, To, Y., additional, Mårtensson, L., additional, Teige, I., additional, Acton, G., additional, Dyer, M.J., additional, Radford, J., additional, Collins, G.P., additional, Jerkeman, M., additional, Frendéus, B., additional, McAllister, A., additional, and Davies, A., additional
- Published
- 2019
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7. Role of fimbriae-mediated adherence for neutrophil migration across Escherichia coli-infected epithelial cell layers
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Godaly, G., Frendéus, B., Proudfoot, A., Svensson, M., Klemm, P., and Svanborg, C.
- Published
- 1998
8. Neutrophil recruitment, chemokine receptors and resistance to mucosal infection
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Godaly, G, Bergsten, G, Hang, L, Fischer, H, Frendéus, B, Lundstedt, A-C, Samuelsson, M, Ellström, Patrik, Svanborg, C, Godaly, G, Bergsten, G, Hang, L, Fischer, H, Frendéus, B, Lundstedt, A-C, Samuelsson, M, Ellström, Patrik, and Svanborg, C
- Published
- 2001
9. The 'innate' host response protects and damages the infected urinary tract
- Author
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Svanborg, C, Bergsten, G, Fischer, H, Frendéus, B, Godaly, G, Gustafsson, E, Hang, L, Hedlund, M, Karpman, D, Lundstedt, A-C, Samuelsson, M, Ellström, Patrik, Svensson, M, Wullt, B, Svanborg, C, Bergsten, G, Fischer, H, Frendéus, B, Godaly, G, Gustafsson, E, Hang, L, Hedlund, M, Karpman, D, Lundstedt, A-C, Samuelsson, M, Ellström, Patrik, Svensson, M, and Wullt, B
- Published
- 2001
10. Innate defenses and resistance to gram negative mucosal infection
- Author
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Godaly, G, Bergsten, G, Frendéus, B, Hang, L, Hedlund, M, Karpman, D, Ellström, Patrik, Svensson, M, Otto, G, Wullt, B, Svanborg, C, Godaly, G, Bergsten, G, Frendéus, B, Hang, L, Hedlund, M, Karpman, D, Ellström, Patrik, Svensson, M, Otto, G, Wullt, B, and Svanborg, C
- Published
- 2000
11. Innate defences and recistance to gram negative mucosal infection
- Author
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Svanborg, C, Frendéus, B, Godaly, G, Hang, L, Hedlund, M, Ellström, Patrik, Svensson, M, Otto, G, Wullt, B, Svanborg, C, Frendéus, B, Godaly, G, Hang, L, Hedlund, M, Ellström, Patrik, Svensson, M, Otto, G, and Wullt, B
- Published
- 1999
12. Neutrophil recruitment, chemokine receptors, and resistance to mucosal infection
- Author
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Godaly, G., primary, Bergsten, G., additional, Hang, L., additional, Fischer, H., additional, Frendéus, B., additional, Lundstedt, A.‐C., additional, Samuelsson, M., additional, Samuelsson, P., additional, and Svanborg, Catharina, additional
- Published
- 2001
- Full Text
- View/download PDF
13. Role of fimbriae-mediated adherence for neutrophil migration acrossEscherichia coli-infected epithelial cell layers
- Author
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Godaly, G., primary, Frendéus, B., additional, Proudfoot, A., additional, Svensson, M., additional, Klemm, P., additional, and Svanborg, C., additional
- Published
- 1998
- Full Text
- View/download PDF
14. Recombinant antibodies to an oxidized low-density lipoprotein epitope induce rapid regression of atherosclerosis in apobec-1(-/-)/low-density lipoprotein receptor(-/-) mice.
- Author
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Schiopu A, Frendéus B, Jansson B, Söderberg I, Ljungcrantz I, Araya Z, Shah PK, Carlsson R, Nilsson J, Fredrikson GN, Schiopu, Alexandru, Frendéus, Björn, Jansson, Bo, Söderberg, Ingrid, Ljungcrantz, Irena, Araya, Zufan, Shah, Prediman K, Carlsson, Roland, Nilsson, Jan, and Fredrikson, Gunilla Nordin
- Abstract
Objectives: The present study tested the hypothesis that treatment with human recombinant immunoglobulin G1 (IgG1) antibodies against a specific oxidized low-density lipoprotein (oxLDL) epitope will induce regression of existing atherosclerotic lesions in LDL receptor-deficient mice expressing apolipoprotein B-100 (apoB-100) (Apobec-1(-/-)/LDLR(-/-)).Background: Oxidized LDL plays an essential role in the pathogenesis of atherosclerosis. We previously showed that an antibody against oxLDL reduces progression of atherosclerosis in mice.Methods: Apobec-1(-/-)/LDLR(-/-) mice were fed a high-fat diet until they were 24 weeks and were subsequently transferred to chow. Starting at 25 weeks, mice were given 3 weekly injections of either of 2 recombinant human IgG1 antibodies (IEI-E3 or 2D03) against a malondialdehyde-modified apoB-100 peptide sequence.Results: At 25 weeks, atherosclerotic lesions covered 10.3 +/- 3.7% of the descending aorta. Transfer to chow diet resulted in a modest regression of atherosclerosis over a 5-week period (8.28 +/- 4.36%; p = NS). Antibody treatment induced additional regression of atherosclerosis by 50% (2D03; p = 0.001) and 36% (IEI-E3; p = 0.004) compared with control IgG1. The 2D03 treatment also reduced plaque inflammation, enhanced plaque expression of the adenosine triphosphate-binding cassette transporter A1, and inhibited expression of monocyte chemoattractant protein-1 in cultured monocytes.Conclusions: Human IgG1 against a specific oxLDL epitope can induce rapid and substantial regression of atherosclerotic lesions, possibly by stimulating lipid efflux and inhibiting macrophage recruitment. These recombinant human antibodies could represent a novel strategy for rapid regression/stabilization of atherosclerotic lesions. [ABSTRACT FROM AUTHOR]- Published
- 2007
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15. B599 Apoptosis-Inducing ICAM-1 Antibody BI-505 Is a Potent Inhibitor of Multiple Myeloma
- Author
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Veitonmäki, NE, Frendeus, B, Danielsson, L, and Ljungars, A
- Published
- 2009
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16. Innate defences and resistance to gram negative mucosal infection
- Author
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Gabriela Godaly, Bergsten, G., Frendéus, B., Hang, L., Hedlund, M., Karpman, D., Samuelsson, P., Svensson, M., Otto, G., Wullt, B., and Svanborg, C.
17. Innate defences and resistance to gram negative mucosal infection
- Author
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Godaly G, Bergsten G, Frendéus B, Hang L, Hedlund M, Diana Karpman, Samuelsson P, Svensson M, Otto G, Wullt B, and Svanborg C
- Subjects
Urinary Tract Infections ,Escherichia coli ,Cytokines ,Humans ,Gram-Negative Bacterial Infections ,Immunity, Mucosal ,Escherichia coli Infections
18. Sequence enrichment profiles enable target-agnostic antibody generation for a broad range of antigens.
- Author
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Mattsson J, Ljungars A, Carlsson A, Svensson C, Nilsson B, Ohlin M, and Frendéus B
- Subjects
- Humans, Antigens, Antibodies, Cell Surface Display Techniques, Peptide Library, Neoplasms
- Abstract
Phenotypic drug discovery (PDD) enables the target-agnostic generation of therapeutic drugs with novel mechanisms of action. However, realizing its full potential for biologics discovery requires new technologies to produce antibodies to all, a priori unknown, disease-associated biomolecules. We present a methodology that helps achieve this by integrating computational modeling, differential antibody display selection, and massive parallel sequencing. The method uses the law of mass action-based computational modeling to optimize antibody display selection and, by matching computationally modeled and experimentally selected sequence enrichment profiles, predict which antibody sequences encode specificity for disease-associated biomolecules. Applied to a phage display antibody library and cell-based antibody selection, ∼10
5 antibody sequences encoding specificity for tumor cell surface receptors expressed at 103 -106 receptors/cell were discovered. We anticipate that this approach will be broadly applicable to molecular libraries coupling genotype to phenotype and to the screening of complex antigen populations for identification of antibodies to unknown disease-associated targets., Competing Interests: J.M., C.S., and B.F. are BioInvent employees, and A.L. was employed by BioInvent. J.M., A.L., and B.F. are shareholders of BioInvent International. J.M., A.L., and B.F. are inventors on BioInvent patent applications relevant to the prediction-guided methodology for antibody discovery., (© 2023 The Author(s).)- Published
- 2023
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19. Targeting FcγRIIB by antagonistic antibody BI-1206 improves the efficacy of rituximab-based therapies in aggressive mantle cell lymphoma.
- Author
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Jiang VC, Liu Y, Jordan A, Leeming A, McIntosh J, Huang S, Zhang R, Cai Q, Chen Z, Li Y, Che Y, Nie L, Karlsson I, Mårtensson L, Kovacek M, Teige I, Frendéus B, and Wang M
- Subjects
- Adult, Animals, Antibodies, Monoclonal, Murine-Derived, Antigens, CD20, Humans, Mice, Neoplasm Recurrence, Local drug therapy, Rituximab pharmacology, Rituximab therapeutic use, Antineoplastic Agents pharmacology, Antineoplastic Agents therapeutic use, Lymphoma, Mantle-Cell drug therapy, Receptors, Chimeric Antigen therapeutic use
- Abstract
Inevitable relapses remain as the major therapeutic challenge in patients with mantle cell lymphoma (MCL) despite FDA approval of multiple targeted therapies and immunotherapies. Fc gamma receptors (FcγRs) play important roles in regulating antibody-mediated immunity. FcγRIIB, the unique immune-checkpoint inhibitory member of the FcγR family, has been implicated in immune cell desensitization and tumor cell resistance to the anti-CD20 antibody rituximab and other antibody-mediated immunotherapies; however, little is known about its expression and its immune-modulatory function in patients with aggressive MCL, especially those with multi-resistance. In this study, we found that FcγRIIB was ubiquitously expressed in both MCL cell lines and primary patient samples. FcγRIIB expression is significantly higher in CAR T-relapsed patient samples (p < 0.0001) compared to ibrutinib/rituximab-naïve, sensitive or resistant samples. Rituximab-induced CD20 internalization in JeKo-1 cells was completely blocked by concurrent treatment with BI-1206, a recombinant human monoclonal antibody targeting FcγRIIB. Combinational therapies with rituximab-ibrutinib, rituximab-venetoclax and rituximab-CHOP also induced CD20 internalization which was again effectively blocked by BI-1206. BI-1206 significantly enhanced the in vivo anti-MCL efficacy of rituximab-ibrutinib (p = 0.05) and rituximab-venetoclax (p = 0.02), but not the rituximab-CHOP combination in JeKo-1 cell line-derived xenograft models. In patient-derived xenograft (PDX) models, BI-1206, as a single agent, showed high potency (p < 0.0001, compared to vehicle control) in one aggressive PDX model that is resistant to both ibrutinib and venetoclax but sensitive to the combination of rituximab and lenalidomide (the preclinical mimetic of R
2 therapy). BI-1206 sensitized the efficacy of rituximab monotherapy in a PDX model with triple resistance to rituximab, ibrutinib and CAR T-therapies (p = 0.030). Moreover, BI-1206 significantly enhanced the efficacy of the rituximab-venetoclax combination (p < 0.05), which led to long-term tumor remission in 25% of mice. Altogether, these data support that targeting this new immune-checkpoint blockade enhances the therapeutic activity of rituximab-based regimens in aggressive MCL models with multi-resistance., (© 2022. The Author(s).)- Published
- 2022
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20. HIF activation enhances FcγRIIb expression on mononuclear phagocytes impeding tumor targeting antibody immunotherapy.
- Author
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Hussain K, Liu R, Smith RCG, Müller KTJ, Ghorbani M, Macari S, Cleary KLS, Oldham RJ, Foxall RB, James S, Booth SG, Murray T, Dahal LN, Hargreaves CE, Kemp RS, Longley J, Douglas J, Markham H, Chee SJ, Stopforth RJ, Roghanian A, Carter MJ, Ottensmeier CH, Frendéus B, Cutress RI, French RR, Glennie MJ, Strefford JC, Thirdborough SM, Beers SA, and Cragg MS
- Subjects
- Animals, Antibodies, Monoclonal pharmacology, Humans, Hypoxia metabolism, Immunotherapy, Macrophages metabolism, Mice, Tumor Microenvironment, Leukemia, Lymphocytic, Chronic, B-Cell metabolism, Receptors, IgG genetics, Receptors, IgG metabolism
- Abstract
Background: Hypoxia is a hallmark of the tumor microenvironment (TME) and in addition to altering metabolism in cancer cells, it transforms tumor-associated stromal cells. Within the tumor stromal cell compartment, tumor-associated macrophages (TAMs) provide potent pro-tumoral support. However, TAMs can also be harnessed to destroy tumor cells by monoclonal antibody (mAb) immunotherapy, through antibody dependent cellular phagocytosis (ADCP). This is mediated via antibody-binding activating Fc gamma receptors (FcγR) and impaired by the single inhibitory FcγR, FcγRIIb., Methods: We applied a multi-OMIC approach coupled with in vitro functional assays and murine tumor models to assess the effects of hypoxia inducible factor (HIF) activation on mAb mediated depletion of human and murine cancer cells. For mechanistic assessments, siRNA-mediated gene silencing, Western blotting and chromatin immune precipitation were utilized to assess the impact of identified regulators on FCGR2B gene transcription., Results: We report that TAMs are FcγRIIb
bright relative to healthy tissue counterparts and under hypoxic conditions, mononuclear phagocytes markedly upregulate FcγRIIb. This enhanced FcγRIIb expression is transcriptionally driven through HIFs and Activator protein 1 (AP-1). Importantly, this phenotype reduces the ability of macrophages to eliminate anti-CD20 monoclonal antibody (mAb) opsonized human chronic lymphocytic leukemia cells in vitro and EL4 lymphoma cells in vivo in human FcγRIIb+/+ transgenic mice. Furthermore, post-HIF activation, mAb mediated blockade of FcγRIIb can partially restore phagocytic function in human monocytes., Conclusion: Our findings provide a detailed molecular and cellular basis for hypoxia driven resistance to antitumor mAb immunotherapy, unveiling a hitherto unexplored aspect of the TME. These findings provide a mechanistic rationale for the modulation of FcγRIIb expression or its blockade as a promising strategy to enhance approved and novel mAb immunotherapies., (© 2022. The Author(s).)- Published
- 2022
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21. Vectorized Treg-depleting αCTLA-4 elicits antigen cross-presentation and CD8 + T cell immunity to reject 'cold' tumors.
- Author
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Semmrich M, Marchand JB, Fend L, Rehn M, Remy C, Holmkvist P, Silvestre N, Svensson C, Kleinpeter P, Deforges J, Junghus F, Cleary KL, Bodén M, Mårtensson L, Foloppe J, Teige I, Quéméneur E, and Frendéus B
- Subjects
- Animals, CD8-Positive T-Lymphocytes, Cell Line, Tumor, Humans, Immune Checkpoint Inhibitors pharmacology, Male, Mice, Antigen Presentation immunology, CTLA-4 Antigen metabolism, Immune Checkpoint Inhibitors therapeutic use, T-Lymphocytes, Regulatory immunology
- Abstract
Background: Immune checkpoint blockade (ICB) is a clinically proven concept to treat cancer. Still, a majority of patients with cancer including those with poorly immune infiltrated 'cold' tumors are resistant to currently available ICB therapies. Cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) is one of few clinically validated targets for ICB, but toxicities linked to efficacy in approved αCTLA-4 regimens have restricted their use and precluded full therapeutic dosing. At a mechanistic level, accumulating preclinical and clinical data indicate dual mechanisms for αCTLA-4; ICB and regulatory T cell (Treg) depletion are both thought to contribute efficacy and toxicity in available, systemic, αCTLA-4 regimens. Accordingly, strategies to deliver highly effective, yet safe αCTLA-4 therapies have been lacking. Here we assess and identify spatially restricted exposure to a novel strongly Treg-depleting, checkpoint-blocking, vectorized αCTLA-4, as a highly efficacious and potentially safe strategy to target CTLA-4., Methods: A novel human IgG1 CTLA-4 antibody (4-E03) was identified using function-first screening for monoclonal antibodies (mAbs) and targets associated with superior Treg-depleting activity. A tumor-selective oncolytic vaccinia vector was then engineered to encode this novel, strongly Treg-depleting, checkpoint-blocking, αCTLA-4 antibody or a matching surrogate antibody, and Granulocyte-macrophage colony-stimulating factor (GM-CSF) (VV
GM -αCTLA-4)., Results: The identified 4-E03 antibody showed significantly stronger Treg depletion, but equipotent checkpoint blockade, compared with clinically validated αCTLA-4 ipilimumab against CTLA-4-expressing Treg cells in a humanized mouse model in vivo. Intratumoral administration of VVGM -αCTLA-4 achieved tumor-restricted CTLA-4 receptor saturation and Treg depletion, which elicited antigen cross-presentation and stronger systemic expansion of tumor-specific CD8+ T cells and antitumor immunity compared with systemic αCTLA-4 antibody therapy. Efficacy correlated with FcγR-mediated intratumoral Treg depletion. Remarkably, in a clinically relevant mouse model resistant to systemic ICB, intratumoral VVGM -αCTLA-4 synergized with αPD-1 to reject cold tumors., Conclusion: Our findings demonstrate in vivo proof of concept for spatial restriction of Treg depletion-optimized immune checkpoint blocking, vectorized αCTLA-4 as a highly effective and safe strategy to target CTLA-4. A clinical trial evaluating intratumoral VVGM -αhCTLA-4 (BT-001) alone and in combination with αPD-1 in metastatic or advanced solid tumors has commenced., Competing Interests: Competing interests: MS, MR, PH, LM, CS, FJ, MB, IT, and BF are employees, MS, MR, LM, FJ, MB, IT, and BF are shareholders of BioInvent International. KLC received funding from BioInvent. J-BM, LF, CR, NS, PK, JD, JF, and EQ are employees and shareholders of Transgene., (© Author(s) (or their employer(s)) 2022. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)- Published
- 2022
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22. Accelerating target deconvolution for therapeutic antibody candidates using highly parallelized genome editing.
- Author
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Mattsson J, Ekdahl L, Junghus F, Ajore R, Erlandsson E, Niroula A, Pertesi M, Frendéus B, Teige I, and Nilsson B
- Subjects
- Antibodies metabolism, CRISPR-Cas Systems genetics, Cell Line, Tumor, Cell Survival genetics, Cell Survival physiology, Clustered Regularly Interspaced Short Palindromic Repeats genetics, Humans, Gene Editing
- Abstract
Therapeutic antibodies are transforming the treatment of cancer and autoimmune diseases. Today, a key challenge is finding antibodies against new targets. Phenotypic discovery promises to achieve this by enabling discovery of antibodies with therapeutic potential without specifying the molecular target a priori. Yet, deconvoluting the targets of phenotypically discovered antibodies remains a bottleneck; efficient deconvolution methods are needed for phenotypic discovery to reach its full potential. Here, we report a comprehensive investigation of a target deconvolution approach based on pooled CRISPR/Cas9. Applying this approach within three real-world phenotypic discovery programs, we rapidly deconvolute the targets of 38 of 39 test antibodies (97%), a success rate far higher than with existing approaches. Moreover, the approach scales well, requires much less work, and robustly identifies antibodies against the major histocompatibility complex. Our data establish CRISPR/Cas9 as a highly efficient target deconvolution approach, with immediate implications for the development of antibody-based drugs.
- Published
- 2021
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23. FcγRIIb Expression Is Decreased on Naive and Marginal Zone-Like B Cells From Females With Multiple Sclerosis.
- Author
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Trend S, Leffler J, Teige I, Frendéus B, Kermode AG, French MA, and Hart PH
- Subjects
- Adult, Antibodies, Viral immunology, B-Cell Activating Factor blood, B-Lymphocyte Subsets immunology, Female, Herpesvirus 4, Human immunology, Humans, Immunoglobulin G immunology, Immunoglobulin M immunology, Interleukin-10 metabolism, Middle Aged, Multiple Sclerosis pathology, Toll-Like Receptor 7 metabolism, Tumor Necrosis Factor-alpha metabolism, B-Lymphocytes immunology, Cytokines metabolism, Multiple Sclerosis immunology, Receptors, IgG metabolism
- Abstract
B cells are critical to the development of multiple sclerosis (MS), but the mechanisms by which they contribute to the disease are poorly defined. We hypothesised that the expression of CD32b (FcγRIIb), a receptor for the Fc region of IgG with inhibitory activities in B cells, is lower on B cell subsets from people with clinically isolated syndrome (CIS) or MS. CD32b expression was highest on post-naive IgM
+ B cell subsets in healthy controls. For females with MS or CIS, significantly lower CD32b expression was identified on IgM+ B cell subsets, including naive and IgMhi MZ-like B cells, when compared with control females. Lower CD32b expression on these B cell subsets was associated with detectable anti-Epstein Barr Virus viral capsid antigen IgM antibodies, and higher serum levels of B cell activating factor. To investigate the effects of lower CD32b expression, B cells were polyclonally activated in the presence of IgG immune complexes, with or without a CD32b blocking antibody, and the expression of TNF and IL-10 in B cell subsets was assessed. The reduction of TNF but not IL-10 expression in controls mediated by IgG immune complexes was reversed by CD32b blockade in naive and IgMhi MZ-like B cells only. However, no consequence of lower CD32b expression on these cells from females with CIS or MS was detected. Our findings highlight a potential role for naive and marginal zone-like B cells in the immunopathogenesis of MS in females, which requires further investigation., Competing Interests: IT and BF were employed by BioInvent International AB. The remaining 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 © 2021 Trend, Leffler, Teige, Frendéus, Kermode, French and Hart.)- Published
- 2021
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24. Deep Mining of Complex Antibody Phage Pools Generated by Cell Panning Enables Discovery of Rare Antibodies Binding New Targets and Epitopes.
- Author
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Ljungars A, Svensson C, Carlsson A, Birgersson E, Tornberg UC, Frendéus B, Ohlin M, and Mattsson M
- Abstract
Phage display technology is a common approach for discovery of therapeutic antibodies. Drug candidates are typically isolated in two steps: First, a pool of antibodies is enriched through consecutive rounds of selection on a target antigen, and then individual clones are characterized in a screening procedure. When whole cells are used as targets, as in phenotypic discovery, the output phage pool typically contains thousands of antibodies, binding, in theory, hundreds of different cell surface receptors. Clonal expansion throughout the phage display enrichment process is affected by multiple factors resulting in extremely complex output phage pools where a few antibodies are highly abundant and the majority is very rare. This is a huge challenge in the screening where only a fraction of the antibodies can be tested using a conventional binding analysis, identifying mainly the most abundant clones typically binding only one or a few targets. As the expected number of antibodies and specificities in the pool is much higher, complementing methods, to reach deeper into the pool, are required, called deep mining methods. In this study, four deep mining methods were evaluated: 1) isolation of rare sub-pools of specific antibodies through selection on recombinant proteins predicted to be expressed on the target cells, 2) isolation of a sub-pool enriched for antibodies of unknown specificities through depletion of the primary phage pool on recombinant proteins corresponding to receptors known to generate many binders, 3) isolation of a sub-pool enriched for antibodies through selection on cells blocked with antibodies dominating the primary phage pool, and 4) next-generation sequencing-based analysis of isolated antibody pools followed by antibody gene synthesis and production of rare but enriched clones. We demonstrate that antibodies binding new targets and epitopes, not discovered through screening alone, can be discovered using described deep mining methods. Overall, we demonstrate the complexity of phage pools generated through selection on cells and show that a combination of conventional screening and deep mining methods are needed to fully utilize such pools. Deep mining will be important in future phenotypic antibody drug discovery efforts to increase the diversity of identified antibodies and targets.
- Published
- 2019
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25. Antibodies to Costimulatory Receptor 4-1BB Enhance Anti-tumor Immunity via T Regulatory Cell Depletion and Promotion of CD8 T Cell Effector Function.
- Author
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Buchan SL, Dou L, Remer M, Booth SG, Dunn SN, Lai C, Semmrich M, Teige I, Mårtensson L, Penfold CA, Chan HTC, Willoughby JE, Mockridge CI, Dahal LN, Cleary KLS, James S, Rogel A, Kannisto P, Jernetz M, Williams EL, Healy E, Verbeek JS, Johnson PWM, Frendéus B, Cragg MS, Glennie MJ, Gray JC, Al-Shamkhani A, and Beers SA
- Subjects
- Animals, Gene Expression, Humans, Immunoglobulin G pharmacology, Lymphocytes, Tumor-Infiltrating immunology, Lymphocytes, Tumor-Infiltrating metabolism, Mice, Mice, Knockout, Neoplasms genetics, Tumor Necrosis Factor Receptor Superfamily, Member 9 genetics, Tumor Necrosis Factor Receptor Superfamily, Member 9 metabolism, Antibodies, Monoclonal pharmacology, CD8-Positive T-Lymphocytes immunology, CD8-Positive T-Lymphocytes metabolism, Immunomodulation drug effects, Neoplasms immunology, Neoplasms metabolism, T-Lymphocytes, Regulatory immunology, T-Lymphocytes, Regulatory metabolism, Tumor Necrosis Factor Receptor Superfamily, Member 9 antagonists & inhibitors
- Abstract
The costimulatory receptor 4-1BB is expressed on activated immune cells, including activated T cells. Antibodies targeting 4-1BB enhance the proliferation and survival of antigen-stimulated T cells in vitro and promote CD8 T cell-dependent anti-tumor immunity in pre-clinical cancer models. We found that T regulatory (Treg) cells infiltrating human or murine tumors expressed high amounts of 4-1BB. Intra-tumoral Treg cells were preferentially depleted by anti-4-1BB mAbs in vivo. Anti-4-1BB mAbs also promoted effector T cell agonism to promote tumor rejection. These distinct mechanisms were competitive and dependent on antibody isotype and FcγR availability. Administration of anti-4-1BB IgG2a, which preferentially depletes Treg cells, followed by either agonistic anti-4-1BB IgG1 or anti-PD-1 mAb augmented anti-tumor responses in multiple solid tumor models. An antibody engineered to optimize both FcγR-dependent Treg cell depleting capacity and FcγR-independent agonism delivered enhanced anti-tumor therapy. These insights into the effector mechanisms of anti-4-1BB mAbs lay the groundwork for translation into the clinic., (Copyright © 2018 Elsevier Inc. All rights reserved.)
- Published
- 2018
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26. Fc Effector Function Contributes to the Activity of Human Anti-CTLA-4 Antibodies.
- Author
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Arce Vargas F, Furness AJS, Litchfield K, Joshi K, Rosenthal R, Ghorani E, Solomon I, Lesko MH, Ruef N, Roddie C, Henry JY, Spain L, Ben Aissa A, Georgiou A, Wong YNS, Smith M, Strauss D, Hayes A, Nicol D, O'Brien T, Mårtensson L, Ljungars A, Teige I, Frendéus B, Pule M, Marafioti T, Gore M, Larkin J, Turajlic S, Swanton C, Peggs KS, and Quezada SA
- Subjects
- Animals, Antibodies, Monoclonal administration & dosage, Antibodies, Monoclonal pharmacology, Antibodies, Monoclonal, Humanized, Antineoplastic Agents, Immunological pharmacology, CTLA-4 Antigen antagonists & inhibitors, Cell Line, Tumor, Female, Humans, Ipilimumab administration & dosage, Ipilimumab pharmacology, Melanoma genetics, Melanoma immunology, Mice, Receptors, IgG metabolism, Treatment Outcome, Xenograft Model Antitumor Assays, Antineoplastic Agents, Immunological administration & dosage, Melanoma drug therapy, Polymorphism, Single Nucleotide, Receptors, IgG genetics, T-Lymphocytes, Regulatory immunology
- Abstract
With the use of a mouse model expressing human Fc-gamma receptors (FcγRs), we demonstrated that antibodies with isotypes equivalent to ipilimumab and tremelimumab mediate intra-tumoral regulatory T (Treg) cell depletion in vivo, increasing the CD8
+ to Treg cell ratio and promoting tumor rejection. Antibodies with improved FcγR binding profiles drove superior anti-tumor responses and survival. In patients with advanced melanoma, response to ipilimumab was associated with the CD16a-V158F high affinity polymorphism. Such activity only appeared relevant in the context of inflamed tumors, explaining the modest response rates observed in the clinical setting. Our data suggest that the activity of anti-CTLA-4 in inflamed tumors may be improved through enhancement of FcγR binding, whereas poorly infiltrated tumors will likely require combination approaches., (Copyright © 2018 The Author(s). Published by Elsevier Inc. All rights reserved.)- Published
- 2018
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27. Diet-Induced Abdominal Obesity, Metabolic Changes, and Atherosclerosis in Hypercholesterolemic Minipigs.
- Author
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Al-Mashhadi AL, Poulsen CB, von Wachenfeldt K, Robertson AK, Bentzon JF, Nielsen LB, Thygesen J, Tolbod LP, Larsen JR, Moestrup SK, Frendéus B, Mortensen B, Drouet L, Al-Mashhadi RH, and Falk E
- Subjects
- Animals, Atherosclerosis etiology, Atherosclerosis pathology, Body Composition physiology, Cholesterol, HDL metabolism, Cholesterol, LDL metabolism, Female, Hypercholesterolemia etiology, Hypercholesterolemia pathology, Intra-Abdominal Fat metabolism, Metabolic Syndrome etiology, Metabolic Syndrome pathology, Obesity, Abdominal etiology, Obesity, Abdominal pathology, Subcutaneous Fat metabolism, Swine, Swine, Miniature, Triglycerides metabolism, Atherosclerosis metabolism, Diet, High-Fat adverse effects, Hypercholesterolemia metabolism, Insulin Resistance physiology, Metabolic Syndrome metabolism, Obesity, Abdominal metabolism
- Abstract
Background: Obesity and metabolic syndrome (MetS) are major risk factors for atherosclerotic diseases; however, a causal link remains elusive. Animal models resembling human MetS and its complications, while important, are scarce. We aimed at developing a porcine model of human MetS., Methods: Forty pigs with familial hypercholesterolemia were fed a high fat + fructose diet for 30 weeks. Metabolic assessments and subcutaneous fat biopsies were obtained at 18 and 30 weeks, and fat distribution was assessed by CT-scans. Postmortem, macrophage density, and phenotype in fat tissues were quantified along with atherosclerotic burden., Results: During the experiment, we observed a >4-fold in body weight, a significant but small increase in fasting glucose (4.1 mmol/L), insulin (3.1 mU/L), triglycerides (0.5 mmol/L), and HDL cholesterol (2.6 mmol/L). Subcutaneous fat correlated with insulin resistance, but intra-abdominal fat correlated inversely with insulin resistance and LDL cholesterol. More inflammatory macrophages were found in visceral versus subcutaneous fat, and inflammation decreased in subcutaneous fat over time., Conclusions: MetS based on human criteria was not achieved. Surprisingly, visceral fat seemed part of a healthier metabolic and inflammatory profile. These results differ from human findings, and further research is needed to understand the relationship between obesity and MetS in porcine models.
- Published
- 2018
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28. Treatment with a human recombinant monoclonal IgG antibody against oxidized LDL in atherosclerosis-prone pigs reduces cathepsin S in coronary lesions.
- Author
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Poulsen CB, Al-Mashhadi AL, von Wachenfeldt K, Bentzon JF, Nielsen LB, Al-Mashhadi RH, Thygesen J, Tolbod L, Larsen JR, Frøkiær J, Tawakol A, Vucic E, Fredrickson J, Baruch A, Frendéus B, Robertson AK, Moestrup SK, Drouet L, and Falk E
- Subjects
- Animals, Atherosclerosis diagnostic imaging, Disease Models, Animal, Female, Fluorodeoxyglucose F18, Humans, Hypercholesterolemia diagnostic imaging, Lipids blood, Positron-Emission Tomography methods, Swine, Treatment Outcome, Antibodies, Monoclonal pharmacology, Atherosclerosis blood, Atherosclerosis drug therapy, Cathepsins blood, Hypercholesterolemia drug therapy, Recombinant Proteins pharmacology
- Abstract
Background: Immunization with oxidized LDL (oxLDL) reduces atherosclerosis in rodents. We tested the hypothesis that treatment with a human recombinant monoclonal antibody against oxLDL will reduce the burden or composition of atherosclerotic lesions in hypercholesterolemic minipigs., Methods and Results: Thirty-eight hypercholesterolemic minipigs with defective LDL receptors were injected with an oxLDL antibody or placebo weekly for 12weeks. An 18F-fluorodeoxyglucose positron emission tomography (FDG PET) scan (n=9) was performed before inclusion and after 3months of treatment. Blood samples were obtained prior to each injection. Following the last injection all animals were sacrificed, and the heart, aorta, and iliac arteries were removed. The left anterior descending coronary artery was sectioned at 5mm intervals for quantitative and qualitative assessments of atherosclerosis, including immunohistochemical phenotyping of macrophages using a pan-macrophage marker (CD68) and markers for putative pro-atherogenic (cathepsin S) and atheroprotective (CD163) macrophages. Aorta, right coronary artery, and left iliac artery were stained en face with Sudan IV and the amount of atherosclerosis quantified. There was no effect of treatment on plasma lipid profile, vascular FDG-PET signal or the amount of atherosclerosis in any of the examined arteries. However, immunostaining of coronary lesions revealed reduced cathepsin S positivity in the treated group compared with placebo (4.8% versus 8.2% of intima area, p=0.03) with no difference in CD68 or CD163 positivity., Conclusions: In hypercholesterolemic minipigs, treatment with a human recombinant monoclonal antibody against oxLDL reduced cathepsin S in coronary lesions without any effect on the burden of atherosclerosis or aortic FDG-PET signal., (Copyright © 2016. Published by Elsevier Ireland Ltd.)
- Published
- 2016
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29. Development and Characterization of Monoclonal Antibodies Specific for Mouse and Human Fcγ Receptors.
- Author
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Tutt AL, James S, Laversin SA, Tipton TR, Ashton-Key M, French RR, Hussain K, Vaughan AT, Dou L, Earley A, Dahal LN, Lu C, Dunscombe M, Chan HT, Penfold CA, Kim JH, Potter EA, Mockridge CI, Roghanian A, Oldham RJ, Cox KL, Lim SH, Teige I, Frendéus B, Glennie MJ, Beers SA, and Cragg MS
- Subjects
- Animals, Bone Marrow immunology, CHO Cells, Cell Line, Cricetinae, Cricetulus, Flow Cytometry, HEK293 Cells, Humans, Mice, Mice, Inbred BALB C, Mice, Inbred C57BL, Mice, Knockout, Palatine Tonsil immunology, Protein Isoforms genetics, Protein Isoforms immunology, Rats, Rats, Wistar, Spleen immunology, Antibodies, Monoclonal immunology, Immunoglobulin G immunology, Receptors, IgG biosynthesis, Receptors, IgG immunology
- Abstract
FcγRs are key regulators of the immune response, capable of binding to the Fc portion of IgG Abs and manipulating the behavior of numerous cell types. Through a variety of receptors, isoforms, and cellular expression patterns, they are able to fine-tune and direct appropriate responses. Furthermore, they are key determinants of mAb immunotherapy, with mAb isotype and FcγR interaction governing therapeutic efficacy. Critical to understanding the biology of this complex family of receptors are reagents that are robust and highly specific for each receptor. In this study, we describe the development and characterization of mAb panels specific for both mouse and human FcγR for use in flow cytometry, immunofluorescence, and immunocytochemistry. We highlight key differences in expression between the two species and also patterns of expression that will likely impact on immunotherapeutic efficacy and translation of therapeutic agents from mouse to clinic., (Copyright © 2015 by The American Association of Immunologists, Inc.)
- Published
- 2015
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30. Resistance is futile: Targeting the inhibitory FcγRIIB (CD32B) to maximize immunotherapy.
- Author
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Roghanian A, Cragg MS, and Frendéus B
- Abstract
Monoclonal antibodies (mAb) are central to the treatment of several types of malignancy. However, these reagents are subject to particular types of resistance. Several resistance mechanisms are regulated by the inhibitory FcγRIIB. We recently developed mAbs to block FcγRIIB and provided in vivo proof-of-concept for their ability to overcome FcγRIIB-mediated resistance.
- Published
- 2015
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31. Antagonistic human FcγRIIB (CD32B) antibodies have anti-tumor activity and overcome resistance to antibody therapy in vivo.
- Author
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Roghanian A, Teige I, Mårtensson L, Cox KL, Kovacek M, Ljungars A, Mattson J, Sundberg A, Vaughan AT, Shah V, Smyth NR, Sheth B, Chan HT, Li ZC, Williams EL, Manfredi G, Oldham RJ, Mockridge CI, James SA, Dahal LN, Hussain K, Nilsson B, Verbeek JS, Juliusson G, Hansson M, Jerkeman M, Johnson PW, Davies A, Beers SA, Glennie MJ, Frendéus B, and Cragg MS
- Subjects
- Animals, Antibodies, Monoclonal pharmacology, Antibodies, Monoclonal, Murine-Derived metabolism, Antibodies, Monoclonal, Murine-Derived pharmacology, Drug Synergism, Humans, Mice, Neoplasms drug therapy, Neoplasms immunology, Receptors, IgG physiology, Rituximab, Antibodies, Monoclonal therapeutic use, Antibodies, Monoclonal, Murine-Derived therapeutic use, Receptors, IgG antagonists & inhibitors
- Abstract
Therapeutic antibodies have transformed cancer therapy, unlocking mechanisms of action by engaging the immune system. Unfortunately, cures rarely occur and patients display intrinsic or acquired resistance. Here, we demonstrate the therapeutic potential of targeting human (h) FcγRIIB (CD32B), a receptor implicated in immune cell desensitization and tumor cell resistance. FcγRIIB-blocking antibodies prevented internalization of the CD20-specific antibody rituximab, thereby maximizing cell surface accessibility and immune effector cell mediated antitumor activity. In hFcγRIIB-transgenic (Tg) mice, FcγRIIB-blocking antibodies effectively deleted target cells in combination with rituximab, and other therapeutic antibodies, from resistance-prone stromal compartments. Similar efficacy was seen in primary human tumor xenografts, including with cells from patients with relapsed/refractory disease. These data support the further development of hFcγRIIB antibodies for clinical assessment., (Copyright © 2015 Elsevier Inc. All rights reserved.)
- Published
- 2015
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32. Upregulation of FcγRIIb on monocytes is necessary to promote the superagonist activity of TGN1412.
- Author
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Hussain K, Hargreaves CE, Roghanian A, Oldham RJ, Chan HT, Mockridge CI, Chowdhury F, Frendéus B, Harper KS, Strefford JC, Cragg MS, Glennie MJ, Williams AP, and French RR
- Subjects
- Animals, B-Lymphocytes cytology, CD28 Antigens metabolism, CHO Cells, Cell Proliferation, Coculture Techniques, Cricetinae, Cricetulus, Cytokines metabolism, Humans, Leukocytes, Mononuclear cytology, T-Lymphocytes cytology, T-Lymphocytes immunology, Transfection, Antibodies, Monoclonal, Humanized chemistry, Monocytes cytology, Receptors, IgG metabolism, Up-Regulation
- Abstract
The anti-CD28 superagonist antibody TGN1412 caused life-threatening cytokine release syndrome (CRS) in healthy volunteers, which had not been predicted by preclinical testing. T cells in fresh peripheral blood mononuclear cells (PBMCs) do not respond to soluble TGN1412 but do respond following high-density (HD) preculture. We show for the first time that this response is dependent on crystallizable fragment gamma receptor IIb (FcγRIIb) expression on monocytes. This was unexpected because, unlike B cells, circulating monocytes express little or no FcγRIIb. However, FcγRIIb expression is logarithmically increased on monocytes during HD preculture, and this upregulation is necessary and sufficient to explain TGN1412 potency after HD preculture. B-cell FcγRIIb expression is unchanged by HD preculture, but B cells can support TGN1412-mediated T-cell proliferation when added at a frequency higher than that in PBMCs. Although low-density (LD) precultured PBMCs do not respond to TGN1412, T cells from LD preculture are fully responsive when cocultured with FcγRIIb-expressing monocytes from HD preculture, which shows that they are fully able to respond to TGN1412-mediated activation. Our novel findings demonstrate that cross-linking by FcγRIIb is critical for the superagonist activity of TGN1412 after HD preculture, and this may contribute to CRS in humans because of the close association of FcγRIIb-bearing cells with T cells in lymphoid tissues., (© 2015 by The American Society of Hematology.)
- Published
- 2015
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33. Inhibitory FcγRIIb (CD32b) becomes activated by therapeutic mAb in both cis and trans and drives internalization according to antibody specificity.
- Author
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Vaughan AT, Iriyama C, Beers SA, Chan CH, Lim SH, Williams EL, Shah V, Roghanian A, Frendéus B, Glennie MJ, and Cragg MS
- Subjects
- Antibodies, Monoclonal metabolism, Antibody Specificity, Antigens, CD20 immunology, B-Lymphocytes immunology, B-Lymphocytes metabolism, Humans, Protein Isoforms immunology, Protein Transport, Antibodies, Monoclonal immunology, Receptors, IgG immunology
- Abstract
A major feature that distinguishes type I from type II anti-CD20 monoclonal antibodies (mAbs) and reduces their therapeutic efficacy is the tendency to internalize from the cell surface. We have shown previously that the extent of internalization correlates with the capacity of type I mAb to simultaneously engage both CD20 and the inhibitory Fcγ receptor, FcγRIIb, in a bipolar configuration. Here, we investigated whether mAbs directed at other B-cell surface receptors also engaged FcγRIIb and whether this interaction promoted internalization. Most mAbs engaged and activated FcγRIIb, with the strength of activation related to the level of mAb bound to the cell surface. However, engagement did not affect internalization of most mAb-ligated receptors, either in cell lines or primary chronic lymphocytic leukemia cells with the exception of CD19 and CD38. Furthermore, at high cell concentrations/density both cis and trans interactions between cell-surface bound mAb and FcγRIIb were evident, but trans interactions did not inhibit type I anti-CD20 mAb-mediated internalization. These data identify that FcγRIIb is engaged by many mAbs in both cis and trans configurations, triggering its activation, but that internalization via FcγRIIb occurs for only a select subset. These findings have implications when designing new antibody-based therapeutics.
- Published
- 2014
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34. Function-first antibody discovery: Embracing the unpredictable biology of antibodies.
- Author
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Frendéus B
- Abstract
Therapeutic antibodies may mediate antineoplastic effects by altering the biological functions of their target, by directly stimulating the demise of cancer cells or by activating antibody-dependent immune effector mechanisms. We have recently provided in vivo proof-of-concept for a "function-first" target and drug discovery platform in which antibodies against a multitude of tumor-associated antigens are screened for biological effects in a target-unbiased manner.
- Published
- 2013
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35. Targeting oxidized LDL improves insulin sensitivity and immune cell function in obese Rhesus macaques.
- Author
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Li S, Kievit P, Robertson AK, Kolumam G, Li X, von Wachenfeldt K, Valfridsson C, Bullens S, Messaoudi I, Bader L, Cowan KJ, Kamath A, van Bruggen N, Bunting S, Frendéus B, and Grove KL
- Abstract
Oxidation of LDL (oxLDL) is a crucial step in the development of cardiovascular disease. Treatment with antibodies directed against oxLDL can reduce atherosclerosis in rodent models through unknown mechanisms. We demonstrate that through a novel mechanism of immune complex formation and Fc-γ receptor (FcγR) engagement, antibodies targeting oxLDL (MLDL1278a) are anti-inflammatory on innate immune cells via modulation of Syk, p38 MAPK phosphorylation and NFκB activity. Subsequent administration of MLDL1278a in diet-induced obese (DIO) nonhuman primates (NHP) resulted in a significant decrease in pro-inflammatory cytokines and improved overall immune cell function. Importantly, MLDL1278a treatment improved insulin sensitivity independent of body weight change. This study demonstrates a novel mechanism by which an anti-oxLDL antibody improves immune function and insulin sensitivity independent of internalization of oxLDL. This identifies MLDL1278a as a potential therapy for reducing vascular inflammation in diabetic conditions.
- Published
- 2013
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36. A human ICAM-1 antibody isolated by a function-first approach has potent macrophage-dependent antimyeloma activity in vivo.
- Author
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Veitonmäki N, Hansson M, Zhan F, Sundberg A, Löfstedt T, Ljungars A, Li ZC, Martinsson-Niskanen T, Zeng M, Yang Y, Danielsson L, Kovacek M, Lundqvist A, Mårtensson L, Teige I, Tricot G, and Frendéus B
- Subjects
- Adult, Aged, Aged, 80 and over, Animals, Antibodies, Monoclonal immunology, Antibodies, Monoclonal isolation & purification, B-Lymphocytes metabolism, Cell Line, Tumor, Epitopes biosynthesis, Epitopes immunology, Female, Humans, Macrophages metabolism, Male, Mice, Mice, SCID, Middle Aged, Multiple Myeloma drug therapy, Multiple Myeloma metabolism, Peptide Library, Receptors, IgG immunology, Xenograft Model Antitumor Assays, Antibodies, Monoclonal pharmacology, B-Lymphocytes immunology, Intercellular Adhesion Molecule-1 immunology, Macrophages immunology, Multiple Myeloma immunology, Multiple Myeloma therapy
- Abstract
We isolated a tumor B-cell-targeting antibody, BI-505, from a highly diversified human phage-antibody library, using a pioneering "function-first" approach involving screening for (1) specificity for a tumor B cell surface receptor, (2) induction of tumor programmed cell death, and (3) enhanced in vivo antitumor activity compared to currently used treatments. BI-505 bound to intercellular adhesion molecule-1, identifying a previously unrecognized role for this receptor as a therapeutic target in cancer. The BI-505 epitope was strongly expressed on the surface of multiple myeloma cells from both newly diagnosed and relapsed patients. BI-505 had potent macrophage-dependent antimyeloma activity and conferred enhanced survival compared to currently used treatments in advanced experimental models of multiple myeloma., (Copyright © 2013 Elsevier Inc. All rights reserved.)
- Published
- 2013
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- View/download PDF
37. Design of recombinant antibody microarrays for cell surface membrane proteomics.
- Author
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Dexlin L, Ingvarsson J, Frendéus B, Borrebaeck CA, and Wingren C
- Subjects
- Equipment Design, Humans, Immunoglobulin Fragments, Membrane Proteins analysis, Recombinant Proteins, Antibodies, Antigens, Surface analysis, Protein Array Analysis, Proteomics methods
- Abstract
Generating proteomic maps of membrane proteins, common targets for therapeutic interventions and disease diagnostics, has turned out to be a major challenge. Antibody-based microarrays are among the novel rapidly evolving proteomic technologies that may enable global proteome analysis to be performed. Here, we have designed the first generation of a scaleable human recombinant scFv antibody microarray technology platform for cell surface membrane proteomics as well as glycomics targeting intact cells. The results showed that rapid and multiplexed profiling of the cell surface proteome (and glycome) could be performed in a highly specific and sensitive manner and that differential expression patterns due to external stimuli could be monitored.
- Published
- 2008
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38. Rapid induction of apoptosis in B-cell lymphoma by functionally isolated human antibodies.
- Author
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Fransson J, Tornberg UC, Borrebaeck CA, Carlsson R, and Frendéus B
- Subjects
- Antibodies immunology, Flow Cytometry, HLA-DP Antigens immunology, HLA-DR Antigens immunology, Humans, Immunoglobulin G immunology, Immunoglobulin Variable Region immunology, Immunoglobulin mu-Chains immunology, Immunohistochemistry, Intercellular Adhesion Molecule-1 immunology, Lymphoma, B-Cell pathology, Apoptosis immunology, Lymphoma, B-Cell immunology
- Abstract
Novel panning and screening methodology was devised to isolate high affinity human recombinant scFv antibody fragments with functionally associated properties in B lymphoma cells. The approach was used to generate a panel of apoptosis-inducing antibodies specific for antigens differentially expressed in B lymphoma vs. T leukaemia cells. The selections resulted in an antibody pool with near perfect selectivity (>99%) for the B lymphoma target cells. Randomly picked clones (72) revealed 7 unique antibody genotypes. Six of these rapidly induced apoptosis in target cells. Following the conversion to full IgGs, the antibodies were shown to be specific for HLA-DR/DP, the B-cell receptor mu chain and for CD54/ICAM-1. The latter receptor was not previously associated with apoptotic properties in B-cell lymphomas. Anti-ICAM-1 IgG induced apoptosis in a broad range of B lymphoma cell lines and were shown by immunohistochemistry to bind strongly to B lymphoma tissue obtained from 5 different B lymphoma patients. The recombinant IgG antibodies had affinities in the subnanomolar (0.3 nM) to nanomolar (3 nM) range. The described technology is generally applicable for the rapid isolation of high affinity human antibodies with specificity for differentially expressed cell surface receptors with intrinsic negative or positive signalling properties from naïve phage libraries., (2006 Wiley-Liss, Inc.)
- Published
- 2006
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39. The 'innate' host response protects and damages the infected urinary tract.
- Author
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Svanborg C, Bergsten G, Fischer H, Frendéus B, Godaly G, Gustafsson E, Hang L, Hedlund M, Karpman D, Lundstedt AC, Samuelsson M, Samuelsson P, Svensson M, and Wullt B
- Subjects
- Animals, Carrier State, Escherichia coli, Fimbriae, Bacterial, Genetic Predisposition to Disease, Humans, Membrane Glycoproteins genetics, Mice, Mice, Inbred C3H, Mice, Knockout, Neutrophil Infiltration, Pyelonephritis genetics, Receptors, Cell Surface genetics, Receptors, Interleukin-8A genetics, Signal Transduction, Toll-Like Receptor 4, Toll-Like Receptors, Drosophila Proteins, Urinary Tract Infections genetics, Urinary Tract Infections immunology
- Abstract
Symptoms of infection and tissue pathology are caused by the host response; not by the microbe per se. The same response is also critical for the defence and is needed to clear infection. It is therefore essential to understand how the host response is activated and to identify the critical effector mechanisms of the defence. We have studied these issues in the urinary tract infection (UTI) model. The symptoms of UTI and the host defence both rely on the so-called 'innate' immune system, making this one of the best characterized human disease models of 'innate immunity. We discuss the critical molecular events that determine whether the host response will be activated by P-fimbriated uropathogenic Escherichia coli as well as factors determining whether the patient develops acute pyelonephritis or asymptomatic bacteriuria. We will describe the glycoconjugate receptors used by the P-fimbriated bacteria adhering to host tissues, the recruitment of TLR4 co-receptors and the signalling pathways that allow progression to symptomatic disease, and discuss how these mechanisms are altered in asymptomatic carriers, presenting the possible genetic basis for unresponsiveness. We have shown that neutrophils are the critical effectors of the host defence and that neutrophil dysfunctions lead to acute pyelonephritis and renal scarring. Here we discuss the mechanisms of neutrophil-mediated, chemokine receptor (CXCR1)-dependent clearance, and the defect in interleukin-8 receptor homolog knock-out (IL-8Rh KO) mice and describe the data linking low CXCR1 expression to recurrent pyelonephritis in man, as well as the information on the genetic basis for low CXCR1 expression in affected patients. Finally, the mechanisms of renal scarring in IL8Rh KO mice will be discussed in relation to human disease. Our studies hold the promise to provide a molecular and genetic explanation for disease susceptibility in some patients with UTI and to offer more precise tools for the diagnosis and therapy of these infections.
- Published
- 2001
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40. Escherichia coli P fimbriae utilize the Toll-like receptor 4 pathway for cell activation.
- Author
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Frendéus B, Wachtler C, Hedlund M, Fischer H, Samuelsson P, Svensson M, and Svanborg C
- Subjects
- Animals, Base Sequence, Cell Line, Cytokines metabolism, DNA Primers, Genotype, Humans, Membrane Glycoproteins genetics, Mice, RNA, Messenger genetics, RNA, Messenger metabolism, Receptors, Cell Surface genetics, Toll-Like Receptor 4, Toll-Like Receptors, Urinary Tract microbiology, Drosophila Proteins, Escherichia coli metabolism, Fimbriae, Bacterial metabolism, Membrane Glycoproteins metabolism, Receptors, Cell Surface metabolism
- Abstract
Fimbriae mediate bacterial attachment to host cells and provide a mechanism for tissue attack. They activate a host response by delivery of microbial products such as lipopolysaccharide (LPS) or through direct fimbriae-dependent signalling mechanisms. By coupling to glycosphingolipid (GSL) receptors, P fimbriae trigger cytokine responses in CD14 negative host cells. Here we show that P fimbriae utilize the Toll-like receptor 4 (TLR4)-dependent pathway to trigger mucosal inflammation. Escherichia coli strains expressing P fimbriae as their only virulence factor stimulated chemokine and neutrophil responses in the urinary tract of TLR4 proficient mice, but TLR4 defective mice failed to respond to infection. Mucosal cells were CD14 negative but expressed several TLR species including TLR4, and TLR4 protein was detected. Infection with P fimbriated bacteria stimulated an increase in TLR4 mRNA levels. The activation signal did not involve the LPS-CD14 pathway and was independent of lipid A myristoylation, as shown by mutational inactivation of the msbB gene. Co-staining experiments revealed that TLR4 and the GSL receptors for P fimbriae co-localized in the cell membrane. The results demonstrate that P fimbriae activate epithelial cells by means of a TLR4-dependent signalling pathway, and suggest that GSL receptors for P fimbriae can recruit TLR4 as co-receptors.
- Published
- 2001
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41. Interleukin-8 receptor deficiency confers susceptibility to acute pyelonephritis.
- Author
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Frendéus B, Godaly G, Hang L, Karpman D, and Svanborg C
- Subjects
- Animals, Child, Child, Preschool, Disease Susceptibility immunology, Disease Susceptibility pathology, Female, Humans, Mice, Mice, Inbred C3H, Mice, Knockout, Neutrophils immunology, Pyelonephritis pathology, Receptors, Chemokine biosynthesis, Receptors, Chemokine immunology, Receptors, Interleukin-8A genetics, Receptors, Interleukin-8A immunology, Recurrence, Urinary Tract Infections microbiology, Urinary Tract Infections pathology, Pyelonephritis immunology, Receptors, Interleukin-8A deficiency, Urinary Tract Infections immunology
- Published
- 2001
- Full Text
- View/download PDF
42. Type 1 fimbriae deliver an LPS- and TLR4-dependent activation signal to CD14-negative cells.
- Author
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Hedlund M, Frendéus B, Wachtler C, Hang L, Fischer H, and Svanborg C
- Subjects
- Animals, Bacterial Adhesion, Cytokines metabolism, Escherichia coli physiology, Escherichia coli Infections immunology, Escherichia coli Infections microbiology, Female, Humans, Membrane Glycoproteins genetics, Mice, Mice, Inbred C3H, Receptors, Cell Surface genetics, Signal Transduction, Toll-Like Receptor 4, Toll-Like Receptors, Tumor Cells, Cultured, Urinary Tract Infections immunology, Urinary Tract Infections microbiology, Drosophila Proteins, Escherichia coli pathogenicity, Fimbriae, Bacterial metabolism, Lipopolysaccharide Receptors metabolism, Lipopolysaccharides metabolism, Membrane Glycoproteins metabolism, Receptors, Cell Surface metabolism
- Abstract
Fimbriae target bacteria to different mucosal surfaces and enhance the inflammatory response at these sites. Inflammation may be triggered by the fimbriae themselves or by fimbriae-dependent delivery of other host activating molecules such as lipopolysaccharide (LPS). Although LPS activates systemic inflammation through the CD14 and Toll-like receptor 4 (TLR4) pathways, mechanisms of epithelial cell activation by LPS are not well understood. These cells lack CD14 receptors and are unresponsive to pure LPS, but fimbriated Escherichia coli overcome this refractoriness and trigger epithelial cytokine responses. We now show that type 1 fimbriae can present an LPS- and TLR4-dependent signal to the CD14-negative epithelial cells. Human uroepithelial cells were shown to express TLR4, and type 1 fimbriated E. coli strains triggered an LPS-dependent response in those cells. A similar LPS- and fimbriae-dependent response was observed in the urinary tract of TLR4-proficient mice, but not in TLR4-defective mice. The moderate inflammatory response in the TLR4-defective mice was fimbriae dependent but LPS independent. The results demonstrate that type 1 fimbriae present LPS to CD14-negative cells and that the TLR4 genotype determines this response despite the absence of CD14 on the target cells. The results illustrate how the host "sees" LPS and other microbial products not as purified molecules but as complexes, and that fimbriae determine the molecular context in which LPS is presented to host cells.
- Published
- 2001
- Full Text
- View/download PDF
43. Interleukin-8 receptor knockout mice have subepithelial neutrophil entrapment and renal scarring following acute pyelonephritis.
- Author
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Hang L, Frendéus B, Godaly G, and Svanborg C
- Subjects
- Abscess immunology, Acute Disease, Animals, Cicatrix pathology, Disease Models, Animal, Epithelium immunology, Escherichia coli, Fibrosis, Kidney pathology, Mice, Mice, Inbred BALB C, Mice, Knockout, Pyelonephritis pathology, Receptors, Interleukin genetics, Time Factors, Kidney immunology, Neutrophil Infiltration immunology, Pyelonephritis immunology, Receptors, Interleukin deficiency
- Abstract
Interleukin (IL)-8 receptor knockout (KO) mice were shown to have a dysfunctional neutrophil response to urinary tract infection and to develop renal scarring. Intravesical Escherichia coli infection stimulated epithelial chemokine secretion and IL-8 receptor expression in control mice. Neutrophils migrated through the tissues and crossed the epithelial barrier into the urinary tract lumen. In murine IL-8 receptor homologue (mIL-8Rh) KO mice, infection triggered a chemokine response, and neutrophils were recruited but failed to traverse the mucosal barrier and accumulated under the epithelium. After 7 days, control mice were healthy, and infection was cleared, but mIL-8Rh KO mice had swollen kidneys, with neutrophil abscesses and high numbers of bacteria. After 35 days, they developed kidney pathology and renal scarring. The results demonstrate that chemokine receptors drive transepithelial neutrophil migration. In their absence, the neutrophils are trapped, and the tissues are destroyed. This molecular deficiency may determine the progression from acute pyelonephritis to renal scarring.
- Published
- 2000
- Full Text
- View/download PDF
44. Transepithelial neutrophil migration is CXCR1 dependent in vitro and is defective in IL-8 receptor knockout mice.
- Author
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Godaly G, Hang L, Frendéus B, and Svanborg C
- Subjects
- Animals, Cell Communication genetics, Cell Communication immunology, Cell Line, Cell Movement genetics, Epithelial Cells cytology, Epithelial Cells microbiology, Epithelial Cells pathology, Escherichia coli Infections genetics, Escherichia coli Infections immunology, Escherichia coli Infections metabolism, Escherichia coli Infections pathology, Female, Genetic Predisposition to Disease, Humans, Interleukin-8 metabolism, Interleukin-8 physiology, Mice, Mice, Inbred BALB C, Mice, Knockout, Neutrophils cytology, Neutrophils microbiology, Neutrophils pathology, Protein Binding genetics, Protein Binding immunology, Receptors, Interleukin-8A biosynthesis, Receptors, Interleukin-8A deficiency, Receptors, Interleukin-8A genetics, Receptors, Interleukin-8B biosynthesis, Receptors, Interleukin-8B deficiency, Receptors, Interleukin-8B genetics, Urinary Tract Infections genetics, Urinary Tract Infections immunology, Urinary Tract Infections metabolism, Urinary Tract Infections pathology, Urothelium cytology, Urothelium immunology, Urothelium metabolism, Urothelium microbiology, Cell Movement immunology, Epithelial Cells immunology, Neutrophils immunology, Receptors, Interleukin-8A physiology
- Abstract
Neutrophil migration across infected mucosal surfaces is chemokine dependent, but the role of chemokine receptors has not been investigated. In this study, chemokine receptors were shown to be expressed by epithelial cells lining the urinary tract, and to play an essential role for neutrophil migration across the mucosal barrier. Uroepithelial CXCR1 and CXCR2 expression was detected in human urinary tract biopsies, and in vitro infection of human uroepithelial cell lines caused a dramatic increase in both receptors. As a consequence, there was higher binding of IL-8 to the cells and the IL-8-dependent neutrophil migration across the infected epithelial cell layers was enhanced. Abs to IL-8 or to the CXCR1 receptor inhibited this increase by 60% (p<0.004), but anti-CXCR2 Abs had no effect, suggesting that CXCR1 was the more essential receptor in this process. Similar observations were made in the mouse urinary tract, where experimental infection stimulated epithelial expression of the murine IL-8 receptor, followed by a rapid flux of neutrophils into the lumen. IL-8 receptor knockout mice, in contrast, failed to express the receptor, their neutrophils were unable to cross the epithelial barrier, and accumulated in massive numbers in the tissues. These results demonstrate that epithelial cells express CXC receptors and that infection increases receptor expression. Furthermore, we show that CXCR1 is required for neutrophil migration across infected epithelial cell layers in vitro, and that the murine IL-8 receptor is needed for neutrophils to cross the infected mucosa of the urinary tract in vivo.
- Published
- 2000
- Full Text
- View/download PDF
45. Interleukin 8 receptor deficiency confers susceptibility to acute experimental pyelonephritis and may have a human counterpart.
- Author
-
Frendéus B, Godaly G, Hang L, Karpman D, Lundstedt AC, and Svanborg C
- Subjects
- Animals, Disease Models, Animal, Escherichia coli Infections immunology, Female, Gene Expression Regulation immunology, Genetic Predisposition to Disease, Humans, Mice, Mice, Inbred BALB C, Mice, Knockout, Receptors, Interleukin-8A deficiency, Receptors, Interleukin-8A genetics, Receptors, Interleukin-8B deficiency, Receptors, Interleukin-8B genetics, Transcription, Genetic, Urinary Tract Infections genetics, Neutrophils immunology, Pyelonephritis genetics, Pyelonephritis immunology, Receptors, Interleukin-8A physiology, Receptors, Interleukin-8B physiology, Urinary Tract Infections immunology
- Abstract
Neutrophils migrate to infected mucosal sites that they protect against invading pathogens. Their interaction with the epithelial barrier is controlled by CXC chemokines and by their receptors. This study examined the change in susceptibility to urinary tract infection (UTI) after deletion of the murine interleukin 8 receptor homologue (mIL-8Rh). Experimental UTIs in control mice stimulated an epithelial chemokine response and increased chemokine receptor expression. Neutrophils migrated through the tissues to the epithelial barrier that they crossed into the lumen, and the mice developed pyuria. In mIL-8Rh knockout (KO) mice, the chemokine response was intact, but the epithelial cells failed to express IL-8R, and neutrophils accumulated in the tissues. The KO mice were unable to clear bacteria from kidneys and bladders and developed bacteremia and symptoms of systemic disease, but control mice were fully resistant to infection. The experimental UTI model demonstrated that IL-8R-dependent mechanisms control the urinary tract defense, and that neutrophils are essential host effector cells. Patients prone to acute pyelonephritis also showed low CXC chemokine receptor 1 expression compared with age-matched controls, suggesting that chemokine receptor expression may also influence the susceptibility to UTIs in humans. The results provide a first molecular clue to disease susceptibility of patients prone to acute pyelonephritis.
- Published
- 2000
- Full Text
- View/download PDF
46. Innate defences and resistance to gram negative mucosal infection.
- Author
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Godaly G, Bergsten G, Frendéus B, Hang L, Hedlund M, Karpman D, Samuelsson P, Svensson M, Otto G, Wullt B, and Svanborg C
- Subjects
- Cytokines immunology, Escherichia coli immunology, Escherichia coli pathogenicity, Escherichia coli Infections immunology, Humans, Gram-Negative Bacterial Infections immunology, Immunity, Mucosal, Urinary Tract Infections immunology
- Published
- 2000
- Full Text
- View/download PDF
47. Neutrophil recruitment and resistance to urinary tract infection.
- Author
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Haraoka M, Hang L, Frendéus B, Godaly G, Burdick M, Strieter R, and Svanborg C
- Subjects
- Animals, Chemotaxis, Leukocyte, Child, Escherichia coli classification, Escherichia coli immunology, Escherichia coli isolation & purification, Escherichia coli Infections pathology, Female, Humans, Kidney microbiology, Kidney pathology, Kidney physiopathology, Lipopolysaccharides pharmacology, Mice, Mice, Inbred C3H, Pyelonephritis microbiology, Urinary Bladder microbiology, Urinary Bladder pathology, Urinary Bladder physiopathology, Urinary Tract Infections pathology, Escherichia coli Infections physiopathology, Neutrophils physiology, Urinary Tract Infections physiopathology
- Abstract
This study examined the role of neutrophil leukocytes for the antibacterial defense at mucosal infection sites. Urinary tract infection (UTI) was established by injection into the bladder lumen of Escherichia coli 1177, a fully virulent clinical isolate. Infection of C3H/HeN (lpsn, lpsn) mice recruited neutrophils into the urinary tract, and bacteria were cleared from kidneys and bladders. The neutrophil response was absent in C3H/HeJ (lpsd, lpsd) mice, and bacteria persisted in the tissues. Peripheral neutrophil depletion of C3H/HeN mice was subsequently achieved by pretreatment with the granulocyte-specific antibody RB6-8C5. The E. coli-induced neutrophil recruitment was inhibited, as shown by immunohistochemistry and tissue myeloperoxidase quantitation. As a consequence, bacterial clearance from kidneys and bladders was drastically impaired. Antibody treatment of C3H/HeJ mice had only a marginal effect. The results show that neutrophils are essential for bacterial clearance from the urinary tract and that the neutrophil recruitment deficiency in C3H/HeJ mice explains their susceptibility to gram-negative UTI.
- Published
- 1999
- Full Text
- View/download PDF
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