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3. Trends in Nuclear Explosion Monitoring Research & Development - A Physics Perspective

Author

Maceira, Monica, primary, Blom, Philip Stephen, additional, MacCarthy, Jonathan K., additional, Marcillo, Omar Eduardo, additional, Euler, Garrett Gene, additional, Begnaud, Michael Lee, additional, Ford, Sean R., additional, Pasyanos, Michael E., additional, Orris, Gregory J., additional, Foxe, Michael P., additional, Arrowsmith, Stephen J., additional, Merchant, B. John, additional, and Slinkard, Megan E., additional

Published
2017
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8. Progress on Component Evaluation for Nuclear Explosion Monitoring

Author

SANDIA NATIONAL LABS ALBUQUERQUE NM, Hart, Darren, Merchant, B. John, Harris, J. M., SANDIA NATIONAL LABS ALBUQUERQUE NM, Hart, Darren, Merchant, B. John, and Harris, J. M.

Abstract

The Ground-Based Nuclear Explosion Monitoring Research and Development (GNEM R&D) program at Sandia National Laboratories (SNL) is regarded as the primary center for unbiased expertise in testing and evaluation of geophysical sensors and instrumentation for nuclear explosion monitoring. We had four main areas of interest to make progress on this year; this report will cover the advances made in these areas. First is the continued development and research of the three-component coherence technique of Sleeman et al. (2006). We have reverted back to synthetic testing to develop a firm understanding of the arithmetic limitations in processing to recover small value estimates of noise relative to large input signals. We explored the effects of digital quantization of the analog signal, as well as the limitations of the technique in the presence of high signal-to-noise input signals. The second area of interest is the upgrade of our suite of software used to analyze sensors and digitizer data (e.g., to calculate noise floor, time-tag accuracy). This past year has allowed us time to develop the new data model and relevant meta-architecture, proto-type existing algorithms in MATLAB with validation against existing tool sets, and develop sets of reusable modules (e.g., waveform editing tools and test description). Our third area of concentration over the past year focused on testing new components for both Provisional Technical Secretariat and the Air Force Technical Applications Center (AFTAC). Characterization reports were produced for two infrasound sensors, Chaparral Physics model 2.5 low-gain and the Inter-Mountain Labs model SS avalanche sensor as well as one data logger, Geotech Smart24. For the infrasound sensors tested, the test results allow us to conclude that both sensors had sufficiently quiet noise floor to be at or below the Acoustic low-noise model from 0.1 to 7 Hz, which make these sensors suitable to explosion monitoring., Published in the Proceedings of the Monitoring Research Review: Ground-Based Nuclear Explosion Monitoring Technologies (30th) held in Portsmouth, VA on 23-25 Sep 2008, p939-948, 2008. The original document contains color images.

Published
2008

9. Merging Event Catalogs Using Agglomerative Hierarchical Clustering

Author

SANDIA NATIONAL LABS LIVERMORE CA, Lewis, Jennifer E., Ballard, Sanford, Young, Christopher J., Carr, Dorthe B., Gonzales, Antonio I., Merchant, B. J., SANDIA NATIONAL LABS LIVERMORE CA, Lewis, Jennifer E., Ballard, Sanford, Young, Christopher J., Carr, Dorthe B., Gonzales, Antonio I., and Merchant, B. J.

Abstract

Many agencies construct catalogs of the hundreds of seismic events that occur daily around the world. The Ground-Based Nuclear Explosion Monitoring Research and Development (GNEMRD) program merges these catalogs together into a composite catalog containing multiple descriptions of the same seismic event, one from each catalog of interest. The merging process requires associating seismic events in individual catalogs (herein called origins), that are independent estimates of the same seismic event. In this paper we describe application of classical cluster analysis techniques that provide a straightforward and robust solution to this merging problem. The resulting algorithm is much simpler to tune than the rule-based methodology used by EvLoader, which is the application currently used to merge catalogs in the GNEMRD program. For this study, we used a simple agglomerative hierarchical clustering technique to create clusters of similar origins where the various origins in a cluster represent different estimates of the seismic parameters of the same actual seismic event. Similarity between origins is calculated using a difference measure based on latitude, longitude, depth, time, and catalog author. Uncertainty in locations is accounted for by dividing distances between origins and differences in origin time by uncertainty estimates from the catalogs. To enforce the assumption that each catalog contains only a single origin for each event, origins from the same catalog are assigned infinite difference, regardless of other parameter values., Presented at the Conference on Monitoring Research Review: Ground-Based Nuclear Explosion Monitoring Technologies (30th), held in Portsmouth, VA, on 23-25 Sep 2008. Published in the proceedings of the conference, p959-967, 2008. Sponsored in part by the National Nuclear Security Administration (NNSA). The original document contains color images.

Published
2008

11. Monk Parakeets: An Expanding Problem on Power Lines and Other Electrical Utility Structures.

Author

Newman, J. R., Newman, C. M., Lindsay, J. R., Merchant, B., Avery, M. L., and Pruett-Jones, S.

Abstract

The monk parakeet (Myiopsitta monachus), a bird native to South America, was brought to the US in the late 1960s and early 1970s as a pet. They have escaped and now populations breed throughout the US from Florida to New York to Oregon to Texas. In urban and suburban areas in Florida and other states the monk parakeet nests on transmission lines, substations and distribution poles as well as other man-made structures and trees. As a stick building nester, its populations have grown exponentially in the last 10 to 15 years. Their nests on utility structures cause significant electrical reliability problems, increased operation and maintenance costs, and safety concerns. The monk parakeet is an invasive species that is banned in some states, e.g. California, but not in others, e.g. Florida. In the past, control of the monk parakeet involved shooting the birds. This was socially unacceptable and control measures stopped. Presently the most effective short-term control strategy is capture of the birds and removal of the nest. Nest removal without capture of the birds only compounds the problem, as the parakeets will rebuild their nests. Long-term controls for the monk parakeet are not yet developed, however, a chemosterilant, Diazacon, shows promise. This paper describes the effects of monk parakeets to electric utilities and other economic sectors, monk parakeet basic biology, and short-term and long-term control and management strategies. [ABSTRACT FROM AUTHOR]

Published
2008
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17. Imaging with indium111-labeled anticarcinoembryonic antigen monoclonal antibody ZCE-025 of recurrent colorectal or carcinoembryonic antigen-producing cancer in patients with rising serum carcinoembryonic antigen levels and occult metastases.

Author

Patt, Y Z, primary, Lamki, L M, additional, Shanken, J, additional, Jessup, J M, additional, Charnsangavej, C, additional, Ajani, J A, additional, Levin, B, additional, Merchant, B, additional, Halverson, C, additional, and Murray, J L, additional

Published
1990
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18. Effects of cyclophosphamide on the in vivo response of outbred athymic (nude) mice to a thymus-independent antigen (DNP-AGG-Ficoll).

Author

Snippe, H., Merchant, B., Johannessen, L., and Inman, J. K.

Subjects
*IMMUNIZATION, *IMMUNOTHERAPY, *THYMUS, *ANTIGENS, *FICOLL, *LYMPHOCYTES, *B cells, *T cells, *ANTIGEN presenting cells
Abstract

Both nude mice (nu/nu) and their heterozygous littermates (nu/+) were injected with a single IP dose of 300 mg cyclophosphamide (CY)/kg. CY is a known immunosuppressive agent, which affects primarily B lymphocytes. Immunization with the thymus independent antigen DNP-AGG59- Ficoll after CY treatment disclosed that restoration of the primary direct PFC response occurred more rapidly in nude mice than in nu/+ mice. However in these same experiments, the primary indirect PFC response, recovered earlier in nu/+ mice than in nude mice. After CY treatment, secondary indirect PFC responses were delayed in both nude and nu/+ mice, but the greatest effect was seen in nude mice. The data suggest that the presence of T cells has little if any influence on the recovery capacity of those B cells which are destined to become direct PFC. However the recovery of B cells which are destined to produce indirect PFC responses is facilitated by the presence of T cells. [ABSTRACT FROM AUTHOR]

Published
1978

19. The effects of synthetic polymeric agents on immune responses of nude mice.

Author

Gershwin, M.E., Merchant, B., and Steinberg, A.D.

Subjects
*IMMUNE response, *NUDE mouse, *POLYMERS, *NUCLEIC acids
Abstract

Investigates the influence of synthetic polymeric agents on the immune responsiveness of congenitally athymic nude mice by determining the effects of in vivo treatment with polynucleotides and polymeric haptenated antigens on splenic theta-bearing cells. Cell responses to thymic dependent and thymic independent antigens; Absence of acquisition of improved T-cell function in nude mice.

Published
1977

26. Hapten-specific B cell blockade of the immune response to a thymus-independent-1 antigen produced by concomitant administration of a thymus-independent-2 antigen.

Author

Snippe, H., Van Houte, A. J., Inman, J. K., Lizzio, Elaine F., and Merchant, B.

Subjects
HAPTENS, B cells, ANTIGENS, IMMUNE response, THYMUS, CELL populations, MICE
Abstract

CBA/N mice harbour an X-linked B cell defect which is transmitted by CBA/N female mice to their hybrid male progeny. These mice mount normal responses to thymus-dependent (TD) and some thymus-independent (TI-1) antigens, while the response to TI-2 antigens is absent. Hapten-specific plaque-forming cell (PFC) responses to TD antigens can be blockaded by concomitant exposure of these mice to TI-2 antigens bearing the same hapten. This paper investigates in defective mice the blockade of their response to TNP3-LPS (trinitrophenylated lipopolysaccharide, a TI-1 antigen), imposed by DNP59-Ficoll (dinitrophenylated Ficoll, a TI-2 antigen). The effectiveness of the blocking agent, DNP59-Ficoll, differed in various inbred mouse strains: CBA/N × C3H/HeN F1 male > CBA/N female > CBA/N · C3H/HeN F1 female. The role of T cells in the observed hapten-specific blockade phenomenon was investigated using athymic CBA/N nude mice and a B cell tolerogen. Our findings indicate that T cell participation is not essential for the blockade of CBA/N PFC responses and they suggest that direct blockade of TI- and TD-responsive B cell populations is likely to occur. [ABSTRACT FROM AUTHOR]

Published
1984

27. Characterization of immunogenic properties of haptenated liposomal model membranes in mice VII. SYNERGISTIC RESPONSES TO HAPTENATED LIPOSOMES AND HAPTENATED THYMUS-DEPENDENT ANTIGENS IN CBA/N MICE.

Author

Snippe, H., Van Houte, A. J., Janssen, A., Lizzio, Elaine F., Willers, J. M. N., and Merchant, B.

Subjects
MICE, ANTIGENS, THYMUS, FICOLL, LIPOSOMES, DINITROBENZENES
Abstract

CBA/N mice have an X-linked S-cell defect which prevents them from responding to non- mitogenic thymus-independent (T1-2) antigens such as haptenated Ficoll. The CBA/N mice do, however, respond to another group of thymus-independent (TI-2) antigens among which are haptenated liposomes. The F1 male progeny of CBA/N female mice express the same characteristics. Hapten-specific plaque-forming cell (PFC) responses to haptenated proteins (thymus-dependent, TD, antigens) by CSA/N mice and CBA/N × C3H/HeN F1 male mice can be blocked by concomitant exposure to TI-2 antigens bearing the same hapten. Simultaneous exposure to haptenated liposomes (TI- I antigen) and TD antigens, however, results in a synergistic response to the hapten if the antigens share common epitopes. The tripeptide-enlarged hapten dinitrophenyl-β-alanylgly- cylglycine (J), conjugated to phosphatidyl-ethanol- amine (PE) and incorporated into liposomal model membranes, was used throughout the experiments. In F1 male mice the moderate responses to TD antigens could be restored to values equivalent to those seen in F1 female mice. This adjuvant effect of haptenated liposomes is hapten-specific, time-dependent, and restricted to certain structural forms of the liposomes. [ABSTRACT FROM AUTHOR]

Published
1982

28. Variable expression of delayed hypersensitivity in different mouse strains using dimethyl dioctadecyl ammonium bromide as an adjuvant.

Author

Snippe, H., Johannesen, L., Lizzio, Elaine, and Merchant, B.

Subjects
ALLERGIES, SERUM albumin, DINITROBENZENES, HAPTENS, IMMUNOLOGY, LABORATORY mice
Abstract

Delayed-type hypersensitivity measured as footpad swelling was studied in a large number of inbred mouse strains. A conjugate of bovine serum albumin (BSA) with the small 2.4-dinitrophenyl (DNP) hapten served to generate strong reactions, specific for the DNP group. Delayed hypersensitivity was produced with the DNP-BSA complex mixed with the cationic, surface active lipid. dimethyl dioctadecyl ammonium bromide (DDA). Great variation was observed in delayed hypersensitivity among different mouse strains. For convenience, the mice were classified into five groups, notably: non-, low, moderate, good and high responders. The highest responding animals were HALB/cJ mice, the lowest were PJJN and outbred nu/nu mice. No correlation was observed between 1-1-2 type and the intensity of the elicited reactions. [ABSTRACT FROM AUTHOR]

Published
1980

29. The specificity of antibody formation in mice following immunization with hapten-carrier complexes mixed with the surfactant, dimethyl dioctadecyl ammonium bromide.

Author

Snippe, H., Willers, J. M. N., Inman, J. K., and Merchant, B.

Subjects
IMMUNIZATION, IMMUNOGLOBULINS, HAPTENS, SURFACE active agents, SERUM albumin, LABORATORY mice
Abstract

Mice were immunized i.e. with various enlarged haptens conjugated to bovine serum albumin and mixed with the cationic, surface active lipid, dimethyl dioctadecyl ammonium bromide (DDA). This immunization generated delayed-type hypersensitivity (DH) in these mice without detectable concomitant antibody formation. The DH was measured as footpad swelling. However, both direct and indirect hapten-specific PFC could be detected in peripheral lymph nodes and in spleens 4 days after a challenge injection. Although the adjuvant, DDA, promotes a strong cross-reactivity in DH between heterologous hapten--carrier complexes, the antibody-forming cells produced 4 days after challenge showed relatively high specificity for the immunizing hapten. This indicates only weak cross-reactivity at the anti-body-forming cell level co-existent with high cross-reactivity in DH expression to the same hapten-carrier complexes. These results are consistent with the possibility that B-cell receptors may be capable of expressing a greater degree of hapten specificity than T-cell receptors. It is tentatively concluded that Thelper cells participating in antibody formation may represent a subset of the T cells involved in DH. [ABSTRACT FROM AUTHOR]

Published
1980

32. Specificity of murine delayed-type hypersensitivity to conjugates of large or small haptens on protein carriers bearing lipid groups.

Author

Snippe, H., Johannesen, Lynne, Inman, J.K., and Merchant, B.

Subjects
DELAYED hypersensitivity, MICE, SERUM albumin, HAPTENS, ANTIGENS, CARRIER proteins, BROMIDES
Abstract

Delayed-type hypersensitivity (DH) in the mouse was provoked with different haptencarrier complexes mixed with the cationic, surfaceactive lipid, dimethyl dioctadecyl ammonium bromide (DDA). DH was measured as footpad swelling.Conjugates of bovine serum albumin (BSA) with the small haptens dinitrophenyl (DNP), 'arsonate'(ARS) and 'sulphonate' (SULPH) served to generate strong DH reactions towards the homologous antigen. Insertion of a tripeptide spacer between the hapten and carrier resulted in lower DH reactivity. Optimal dosages and optimal time intervals between sensitization and DH elicitation were determined for the enlarged hapten-carrier complexes. Cyclophosphamide (CY) treatment, before priming with complexes mixed with DDA, caused a 5-6 day delay in the expression of DH but failed to evoke enhanced DH for any of the antigens tested. A broad array of cross reactions between small and enlarged hapten-carrier complexes showed a relative lack of specificity in these DH responses. The results are compared with others reported in the literature and are explained mainly by the effects of electrostatically bound lipid groups of DDA in the sensitizing conjugates. [ABSTRACT FROM AUTHOR]

Published
1978

41. Increased Multiclonal Antibody-Forming Cell Activity in the Peripheral Blood of Patients with SLE

Author

Reeves Jp, Becker Tm, Merchant B, Lizzio Ef, and Alfred D. Steinberg

Subjects
Antibody forming cell, Guinea Pigs, Immunology, Hemolytic Plaque Technique, Antibodies, Disease activity, immune system diseases, Animals, Humans, Lupus Erythematosus, Systemic, Immunology and Allergy, Medicine, Antibody-Producing Cells, skin and connective tissue diseases, B cell, Sheep, biology, business.industry, Complement C3, DNA, General Medicine, Peripheral blood, Clone Cells, medicine.anatomical_structure, biology.protein, Rabbits, Elevated igm, Antibody, business, Hapten
Abstract

21 patients with criteria for systemic lupus erythematosus (SLE) and 12 normal controls were studied for their spontaneous circulating IgM and IgG plaque-forming cells (PFCs) reactive against sheep erythrocytes (SRBC) and against a panel of five haptens. Quantitatively defined active and mildly active SLE patients had significantly elevated IgM- and IgG-producing PFCs in their peripheral blood reactive with the panel of five chemically defined haptens. Those patients having inactive SLE also showed increased circulating IgM PFCs. Significant elevations in circulating hapten-reactive PFCs were found to correlate progressively with disease activity in the inactive, mildly active, and active SLE patient groups. Circulating IgM- and IgG-secreting PFC reactive against SRBC were both significantly elevated only in those patients with active SLE. The data support the concept that SLE patients have a generalized increase in B cell activity against a broad repertoire of determinants, even those ostensibly unrelated to natural tissue antigens.

Published
1981

43. Hapten-specific hemolytic plaque assays usually fail to detect most of the diversity in the anti-hapten response.

Author

Merchant, B and Inman, J K

Abstract

Immunization of rabbits or mice with a single, chemically defined hapten elicits populations of plaque-forming cells (PFC) detectable not only on sheep erythrocytes (SRBC) bearing the immunizing hapten, but also on SRBC bearing structural analogues of the immunizing hapten. Most of these analogue-reactive PFC preferentially lyse analogue-conjugated SRBC and cannot be detected on erythrocytes bearing the immunizing hapten. Thus, they represent heretofore largely unstudied components of the secretory B-cell response to haptenic immunization, and they have been termed alloreactive PFC. Such alloreactive PFC are detectable using either classical small haptens or tripeptide-enlarged counterparts of these classical haptens. They are present in large numbers both in direct and in indirect PFC assays, and they are elicited in response to both thymic-dependent and thymic-independent antigens. Relatively few alloreactive PFC can be attributed to cells producing hapten-carrier or "bridge area"-specific antibodies. Since the antibodies released by alloreactive PFC can also be detected by passive hemagglutination, their presence does not appear attributable to vagaries of complement activation. Numerous coexisting alloreactive PFC populations are detectable after haptenic immunization. In early direct PFC responses it is not nucommon for a single alloreactive PFC population to outnumber the population of PFC detectable on SRBC bearing the actual immunizing hapten. These alloreactive PFC may be the source of at least some of the new "nonspecific" Ig which is formed at the time of immunization but about which little is known for lack of available techniques. Some possible implications of these findings on the specificity of B precursor cell activation are discussed.

Published
1977
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44. Nuclear antigen detected in hepatoma cell lines containing integrated hepatitis B virus DNA

Author

Wen, Y M, Mitamura, K, Merchant, B, Tang, Z Y, and Purcell, R H

Abstract

We identified, by anticomplement immunofluorescence, a nuclear antigen (hepatitis B virus-associated nuclear antigen [HBNA]) in two human hepatoma cell lines containing integrated hepatitis B virus DNA but not in three hepatoma cell lines lacking it. The antigen resembled neoantigens associated with the oncogenesis of certain papovaviruses, adenoviruses, and herpesviruses. Antibody to the antigen (anti-HBNA) was found in 7.3% of hepatitis B surface antigen-positive sera from patients with hepatocellular carcinoma but not in surface antigen-negative sera. The staining of HBNA was characterized by two patterns, reticular nuclear fluorescence and nucleolar fluorescence. The expression of HBNA did not parallel the production of extracellular hepatitis B surface antigen. Treatment of cells with proteinase K, RNase, DNase, or cycloheximide significantly diminished the staining of HBNA.

Published
1983
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45. Cellular and molecular requirements for X-linked, hapten-specific B-cell blockade in CBA/N mice.

Author

Merchant, B, Snippe, H, Lizzio, E F, and Inman, J K

Abstract

CBA/N mice, a mutant CBA subline, harbor an X-linked B-cell defect which prevents them from mounting immune responses to certain thymic-independent antigens such as pneumococcal polysaccharides and haptenated-Ficoll derivatives. These mice and the hybrid male progeny of CBA/N females are also exquisitely sensitive to a hapten-specific blockade of their otherwise adequate immune responses to thymic-dependent antigens such as N-2,4-dinitrophenylated-hemocyanin (DNP-KLH). As little as 10 ng of a DNP-Ficoll conjugate given 2 h before immunization with a 5,000-fold greater dosage of DNP-KLH, virtually abolishes the 4th-day direct plaque-forming cell (PFC) response specific for DNP. Responding hybrid (CBA/N x C3H/HeN) female mice are resistant to such blockade even at DNP-Ficoll dosages increased by three orders of magnitude. The DNP hapten and Ficoll must be chemically joined for this blocking effect to occur, and increasing the hapten derivatization of Ficoll increases its blockade-invoking capacity. Significant blockade can be produced by administering DNP-Ficoll as early as 4 days before or as late as 4 h after immunization with DNP-KLH. All currently available data point to the defective B cell as the target of this hapten-polysaccharide-mediated blockade. Mice bearing B memory cells, however, are refractory to such blockade. In addition, DNP-Ficoll injections which cause virtually total blockade of 4th-day primary direct PFC responses to DNP-KLH have little or no effect on the development of DNP-reactive B-cell memory measured at either 8 or 30 days. These findings suggest very different blockade susceptibilities for B cells or their precursors at various stages of differentiative development. Our findings also lead to the formulation of testable hypotheses regarding the mechanism of this selective B-cell blockade phenomenon.

Published
1978
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47. The specificity of antibody formation in mice following immunization with hapten-carrier complexes mixed with the surfactant, dimethyl dioctadecyl ammonium bromide

Author

Snippe, H, Willers, J M, Inman, J K, and Merchant, B

Subjects
Mice, Inbred BALB C, T-Lymphocytes, chemical and pharmacologic phenomena, Hemolytic Plaque Technique, Cross Reactions, Mice, Surface-Active Agents, Antibody Specificity, Antibody Formation, Animals, Female, Hypersensitivity, Delayed, Immunization, Haptens, Research Article
Abstract

Mice were immunized i.c. with various enlarged haptens conjugated to bovine serum albumin and mixed with the cationic, surface active lipid, dimethyl dioctadecyl ammonium bromide (DDA). This immunization generated delayed-type hypersensitivity (DH) in these mice without detectable concomitant antibody formation. The DH was measured as footpad swelling. However, both direct and indirect hapten-specific PFC could be detected in peripheral lymph nodes and in spleens 4 days after a challenge injection. Although the adjuvant, DDA, promotes a strong cross-reactivity in DH between heterologous hapten-carrier complexes, the antibody-forming cells produced 4 days after challenge showed relatively high specificity for the immunizing hapten. This indicates only weak cross-reactivity at the antibody-forming cell level co-existent with high cross-reactivity in DH expression to the same hapten-carrier complexes. These results are consistent with the possibility that B-cell receptors may be capable of expressing a greater degree of hapten specificity than T-cell receptors. It is tentatively concluded that Thelper cells participating in antibody formation may represent a subset of the T cells involved in DH.

Published
1980

48. Effects of cyclophosphamide on the in vivo response of outbred athymic (nude) mice to a thymus-independent antigen (DNP-AGG-Ficoll)

Author

Snippe, H, Merchant, B, Johannessen, L, and Inman, J K

Subjects
B-Lymphocytes, Time Factors, T-Lymphocytes, Lymphocyte Cooperation, Mice, Nude, Cell Count, Hemolytic Plaque Technique, Dinitrobenzenes, Mice, Antibody Formation, Animals, Antigens, Cyclophosphamide, Immunologic Memory, Spleen, Research Article
Abstract

Both nude mice (nu/nu) and their heterozygous littermates (nu/+) were injected with a single IP dose of 300 mg cyclophosphamide (CY)/kg. CY is a known immunosuppressive agent, which affects primarily B lymphocytes. Immunization with the thymus independent antigen DNP-AGG59-Ficoll after CY treatment disclosed that restoration of the primary direct PFC response occurred more rapidly in nude mice than in nu/+ mice. However in these same experiments, the primary indirect PFC response, recovered earlier in nu/+ mice than in nude mice. After CY treatment, secondary indirect PFC responses were delayed in both nude and nu/+ mice, but the greatest effect was seen in nude mice. The data suggest that the presence of T cells has little if any influence on the recovery capacity of those B cells which are destined to become direct PFC. However the recovery of B cells which are destined to produce indirect PFC responses is facilitated by the presence of T cells.

Published
1978

49. The effects of synthetic polymeric agents on immune responses of nude mice

Author

Gershwin, M E, Merchant, B, and Steinberg, A D

Subjects
Mice, Poly I-C, Time Factors, Antibody Formation, Age Factors, Animals, Mice, Nude, Poly A-U, Hemolytic Plaque Technique, Antigens, Research Article
Abstract

The influence of synthetic polymeric agents on the immune responsiveness of congenitally athymic (nude) mice was investigated by determining the effects of in vivo treatment with polynucleotides and polymeric haptenated antigens on splenic theta-bearing cells, on mitogen stimulation and on plaque-forming cell responses to thymic dependent and thymic independent antigens. Contrary to in vitro data, no evidence was obtained to demonstrate in vivo restoration of these immune parameters by the use of non-specific immune enhancers. Further, despite the continued release of lipopolysaccharide from the bowel, older nude mice (10 months old) demonstrated no acquisition of improved T-cell function. Nude mice responded well to the thymic independent antigen p-azobenzenearsonate-N-acetyl-tyrosylglycylglycine (A-TGG) Ficoll. Finally, the class specific responses to the thymic independent antigen DNP-Ficoll were significantly different from those of nu/+ littermate controls, indicating the importance of thymic influences upon the class switching of immunoglobulin responses.

Published
1977

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