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C W Pierce

Publications and source records attributed to C W Pierce.

16 recordsLinked to original sources

Primary in vitro immunogenicity of liposomal model membranes in mouse spleen cell cultures.

Neither 2,4-dinitrophenyl-6-N-aminocaproylphosphatidylethanolamine (DNP-Cap-PE) nor fluoresceinthiocarbamylphosphatidylethanolamine (F1-PE) induces hapten-specific plaque-forming cells (PFC) when incubated with suspensions of spleen cells from unimmunized C57BL/6J mice. However, PFC are produced after incorporation of these synthetic lipid antigens into liposomal model membranes. The in vitro response is characterized by the following: a) it is time and dose dependent; b) the frequency of IgM PFC exceeds IgG PFC; c) both nonadherent and adherent cells are required (2-mercaptoethanol can replace the requirement for adherent cells in some experiments); d) depletion of thymus-derived cells by treatment with anti-theta antiserum plus complement does not diminish the response; e) spleen cells from nude BALB/c mice also produce PFC. Thus, the essential features of the in vivo immunogenicity of DNP-Cap-PE and F1-PE sensitized liposomes, which have been previously described, can be replicated in an in vitro cell culture system.

Aminocaproates

Antigen-specific suppressor T-cell activity in genetically restricted immune spleen cells.

Virgin spleen cells develop comparable primary antibody responses in vitro to syngeneic or allogeneic macrophages (Mphi) bearing the terpolymer L-glutamic acid60-L-alanine30-L-tyrosine10 (GAT), whereas immune spleen cells primed with syngeneic or allogeneic GAT-Mphi develop secondary responses preferentially when stimulated with GAT-Mphi syngeneic to the GAT-Mphi used for priming in vivo. These restrictions are mediated by products of the I-A subregion of the H-2 complex and are operative at the level of the GAT-Mphi-immune helper T-cell interactions. To investigate why these immune spleen cells fail to develop a significant antibody response to GAT-Mphi other than those used for in vivo immunization and determine the mechanism by which the restriction is maintained, spleen cells from virgin and syngeneic or allogeneic GAT-Mphi-primed mice were co-cultured in the presence of GAT-Mphi of various haplotypes. Antibody responses to GAT developed only in the presence of GAT-Mphi syngeneic to the Mphi used for in vivo priming; responses in cultures with GAT-Mphi allogeneic to the priming Mphi, whether these Mphi were syngeneic or allogeneic with respect to the responding spleen cells, were suppressed. The suppression was mediated by GAT-specific radiosensitive T cells. Thus, development of GAT-specific suppressor T cells appears to be a natural consequence of the immune response to GAT in responder as well as nonresponder mice. The implications of stimulation of genetically restricted immune helper T cells, and antigen-specific, but unrestricted, suppressor T cells after immunization with GAT-Mphi in vivo are discussed in the context of regulatory mechanisms in antibody responses.

Animals

Suppressor T-cell activity in responder X nonresponder (C57BL/10 X DBA/1)F1 spleen cells responsive to L-glutamic acid60-L-alanine30-L-tyrosine10.

The ability of spleen cells from (responder X nonresponder)F(1) mice immunized with various GAT-Mphi, GAT-MBSA, and soluble GAT to develop IgG GAT-specific PFC responses in vitro after stimulation with responder and nonresponder parental and F(1) GAT-Mphi, was investigated. F(1) spleen cells from mice immunized with F(1) GAT-Mphi or GAT-MBSA developed secondary responses to responder and nonresponder parental and F(1) GAT- Mphi, but not to unrelated third party GAT-Mphi. Spleen cells from F(1) mice immunized with either parental GAT-Mphi developed secondary responses to F(1) GAT-Mphi and only the parental GAT-Mphi used for immunization in vivo. Soluble GAT-primed F(1) spleen cells responded to F(1) and responder parental, but not nonresponder parental, GAT-Mphi. Simultaneous immunization in vivo with the various GAT-Mphi or GAT-MBSA plus soluble GAT modulated the response pattern of these F(1) spleen cells such that they developed secondary responses only to F(1) and parental responder GAT-Mphi regardless of the response pattern observed after immunization with the various GAT-Mphi or GAT-MBSA alone. These observations demonstrate the critical importance of the physical state of the GAT used for immunization in determining the subsequent response pattern of immune F(1) spleen cells to the parental and F(1) GAT-Mphi. Further, suppressor T cells, capable of inhibiting primary responses to GAT by virgin F(1) spleen cells stimulated by nonresponder parental GAT-Mphi, were demonstrated in spleens of F(1) mice immunized with soluble GAT, but not those primed with F(1) GAT-Mphi. Because responder parental mice develop both helper and suppressor T cells after immunization with GAT-Mphi, and soluble GAT preferentially stimulates suppressor T cells whereas GAT-Mphi stimulate helper T cells in nonresponder parental mice, these observations suggest that distinct subsets of T cells exist in F(1) mice which behave phenotypically as responder and nonresponder parental T cells after immunization with soluble GAT and GAT- Mphi.

Alanine

L-glutamic acid60-L-alanine30-L-tyrosine10 (GAT): A probe for regulatory mechanisms in antibody responses.

The synthetic random terpolymer of L-glutamic acid60-L-alanine30-L-tyrosine10 (GAT) has been used as a probe to investigate regulatory mechanisms in antibody responses in tissue culture systems. In this brief review, the mechanisms of H-2 linked Ir gene control of antibody responses to GAT and genetic restrictions governing Mphi-immune T cell interactions in antibody responses to GAT are summarized.

Alanine

Modulation of immune responses by suppressor T cells.

The activity of suppressor T cells has been demonstrated in almost every phase of the immune response. These regulatory cells modulate both humoral and cell-mediated immunity utilizing antigen-specific and nonspecific mechanisms. For comparative purposes two murine models are described, the nonspecific suppressor T cell stimulated by the mitogen concanavalin A and the antigen-specific suppressor T cell stimulated by injection of the synthetic terpolymer acid 60-L-alanine30-L-tyrosine10 (GAT) in nonresponder mice. These two T cells are similar to expression of Ly alloantigens, ability to inhibit antibody responses, and the mediation of suppression, at least in part, by soluble products. However, differences in radio-resistance and antigenic specificity of the suppressor T cells, as well as differences in molecular characteristics of the soluble factors and their targets suggest that these T cells regulate the immune response by different mechanisms. The relationship of these two suppressor T cells to other nonspecific and antigen-specific suppressor T cells is discussed.

Alanine

Secondary antibody responses in vitro to L-glutamic acid60-L-alanine30-L-tyrosine10 (GAT) by (responder X nonresponder)F1 spleen cells stimulated by parental GAT-macrophages.

The development of IgG L-glutamic Acid60-L-alanine30-L-tyrosine10 (GAT)-specific plaque-forming cell responses in vitro by virgin and immune (responder X nonresponder)F1 spleen cells after stimulation with responder and nonresponder parental GAT-macrophages (Mphi) was investigated. Virgin F1 spleen cells developed comparable primary responses to both parental GAT-Mphi. By contrast, F1 spleen cells from mice immunized with GAT or responder parental GAT-Mphi developed secondary responses after stimulation with only responder parental GAT-Mphi. Spleen cells from F1 mice immunized with nonresponder parental GAT-Mphi developed secondary responses to these GAT-Mphi, but failed to respond to responder parental GAT-Mphi. These results are discussed in the context of genetic restrictions regulating Mphi-T-cell interactions in secondary antibody responses and the possible expression of Ir-gene function in Mphi.

Antibody Formation

Immunosuppressive factor(s) extracted from lymphoid cells of nonresponder mice primed with L-glutamic acid60-L-alanine30-L-tyrosine10 (GAT) II. Cellular source and effect on responder and nonresponder mice.

The synthetic terpolymer of L-glutamic acid60-L-alanine30-L-tyrosine10 (GAT) fails to stimulate development of GAT-specific antibody responses in nonresponder strains of mice, but does stimulate the development of GAT-specific suppressor T cells that inhibit the development of normal anti-GAT antibody responses to GAT complexed to methylated bovine serum albumin (GAT-MBSA). Furthermore, extracts prepared from lymphoid cells of GAT-primed, but not control, nonresponder mice inhibit the development of antibody responses to GAT-MBSA by normal nonresponder mice. This suppression is specific, dose-dependent, and can be readily analyzed in vitro. The suppressive factor is a T-cell product. An extract from GAT-primed DBA/1 mice inhibits the response to GAT-MBSA by spleen cells from histoincompatible strains of mice that are nonresponders to GAT, but not strains that are responders to GAT.

Animals

Immunosuppressive factor(s) extracted from lymphoid cells of nonresponder mice primed with L-glutamic acid60-L-alanine30-L-tyrosine10 (GAT).

The synthetic terpolymer of L-glutamic acid60-L-alanine30-L-tyrosine10 (GAT) not only fails to elicit a GAT-specific antibody response in nonresponder mice, but also prior injection of GAT specifically decreases the ability of nonresponder mice to develop a GAT-specific antibody response to a subsequent challenge with GAT-MBSA. This inhibition is mediated by GAT-specific suppressor T cells. Further, a suppressive factor can be extracted from lymphoid cells of GAT-primed nonresponder mice that inhibits the development of primary GAT-specific antibody responses to GAT-MBSA and to GAT-PRBC- by normal syngeneic mice. The suppressive activity is dose-dependent and absorbed by GAT-Sepharose, but not by BSA-Sepharose. The suppressive activity elutes from a G-100 Sephadex column in the same fraction as ovalbumin, suggesting its m.w. is approximately 45,000 daltons.

Animals

Biological expressions of lymphocyte activation. V. Characterization of a soluble immune response suppressor (SIRS) produced by concanavalin A-activated spleen cells.

Supernatant fluids from murine spleen cell cultures incubated with concanavalin A for 48 hr contain a factor(s), soluble immune response suppressor (SIRS), which suppresses plaque-forming cell responses to sheep erythrocytes by murine spleen cells in vitro. In the present studies, some of the biochemical and biophysical properties of SIRS were investigated. SIRS was non-dialysable; the suppressive activity was stable at 56 degrees C for 30 min, but was destroyed by treatment at 70 degrees C for 30 min, 80 degrees C for 10 min, or at pH 2. The suppressive activity was not absorbed by the stimulating antigen, SRBC, or antisera against murine IgG or mu-chain, suggesting that SIRS does not contain immunoglobulin determinants. Murine spleen and thymus, but not kidney cells, however, absorbed SIRS activity. Enzyme treatments revealed that SIRS was resistant to DNase and RNase, but was destroyed by trypsin and chymotrypsin. In gel filtration with Sephadex G-100, SIRS activity eluted in the fraction corresponding to m.w. in the range between 48,000 and 67,000. With polyacrylamide gel electrophoresis, SIRS activity migrated in the region cathodal to albumin. Isopycnic centrifugation in a cesium chloride gradient suggested that SIRS is a glycoprotein. These supernatant fluids with SIRS activity were also found to contain macrophage migration inhibitory factor (MIF). In the experiments using gel filtration, polyacrylamide gel electrophoresis, and isopycnic centrifugation to fractionate supernatant fluids, SIRS and MIF activity were found in the same fractions, and to date we have been unable to dissociate definitively SIRS activity from MIF activity.

Absorption

Cell-mediated immune responses in vitro. III. Elimination of specific cytotoxic lymphocyte responses by 3H-thymidine suicide.

The role of cellular proliferation in the development of cytotoxic lymphocyte (CL) responses in one-way mixed lymphocyte reactions was investigated by using tritiated thymidine of high specific activity to kill proliferating cells. To develop maximum CL responses, responding lymphoid cells must proliferate for approximately 72 hr; thereafter, precursors of CL appear to differentiate into active CL without further proliferation. Different alloantigen-sensitive precursor cell populations participate in the CL responses to each of two sets of stimulating alloantigens. When cells responding to one set of alloantigens were selectively destroyed after incorporating the hot thymidine, the surviving cells retained the capacity to develop a normal CL response to the second set of alloantigens.

Animals