In vivo, the antibody response in mice to the random terpolymer L-glutamic acid(50)-L-alanine(30)-L-tyrosine(10) (GAT) is controlled by a histocompatibility-linked immune response gene(s). We have studied antibody responses by spleen cells from responder and nonresponder mice to GAT and GAT complexed to methylated bovine serum albumin (GAT-MBSA) in vitro. Cells producing antibodies specific for GAT were enumerated in a modified Jerne plaque assay using GAT coupled to sheep erythrocytes as indicator cells. Soluble GAT stimulated development of IgG GAT-specific plaque-forming cell (PFC) responses in cultures of spleen cells from responder mice, C57Bl/6 (H-2(b)), F(1) (C57 x SJL) (H-2(b/s)), and A/J (H-2(a)). Soluble GAT did not stimulate development of GAT-specific PFC responses in cultures of spleen cells from nonresponder mice, SJL (H-2(s)), B10.S (H-2(s)), and A.SW (H-2(s)). GAT-MBSA stimulated development of IgG GAT-specific PFC responses in cultures of spleen cells from both responder and nonresponder strains of mice. These data correlate precisely with data obtained by measuring the in vivo responses of responder and nonresponder strains of mice to GAT and GAT-MBSA by serological techniques. Therefore, this in vitro system can effectively be used as a model to study the cellular events regulated by histocompatibility-linked immune response genes.

Alanine↗

PubMed1973

Genetic control of immune responses in vitro. II. Cellular requirements for the development of primary plaque-forming cell responses to the random terpolymer 1-glutamic acid 60-1-alanine30-1-tyrosine10 (GAT) by mouse spleen cells in vitro.

The cellular requirements for the development of primary IgG GAT-specific PFC responses in cultures of spleen cells from responder, C57Bl/6, mice stimulated with GAT and GAT-MBSA and in cultures of spleen cells from nonresponder, SJL and B10.S, mice stimulated with GAT-MBSA were investigated. Macrophages were required for development of responses to GAT and GAT-MBSA in cultures of spleen cells from responder mice and for responses to GAT-MBSA in cultures of spleen cells from nonresponder mice. Macrophages from nonresponder mice supported the development of responses to GAT by nonadherent responder spleen cells, indicating that the failure of nonresponder mice to respond to GAT is not due to a macrophage defect. Furthermore, responder macrophages supported the responses of nonadherent, nonresponder spleen cells to SRBC and GAT-MBSA, but not to GAT. This indicates that the capacity to respond to GAT is a function of the nonadherent population which is composed of thymus-derived (T) helper cells and precursors of antibody-producing cells. Treatment of spleen cells with anti-theta serum and complement before culture initiation abolished PFC responses to GAT and GAT-MBSA thus establishing the requirement for T cells in the development of PFC responses to these antigens. Since precursors of antibody-producing cells in nonresponder mice are capable of synthesizing antibody specific for GAT after stimulation with GAT-MBSA and since the response to GAT is thymus-dependent, it appears that nonresponder mice lack GAT-specific helper T cell function.

Alanine↗

PubMed1973

Hapten-specific IgE antibody responses in mice. II. Cooperative interactions between adoptively transferred T and B lymphocytes in the development of IgE response.

The present studies have established conditions for the demonstration of cooperative interactions between specific T and B lymphocyte populations in the development of IgE antibody responses in vivo in mice. This has been accomplished by utilizing a system which permits the successful adoptive transfer to irradiated recipients of DNP-specific secondary IgE responses with spleen cells from suitably primed syngeneic donor mice. Thus, adoptively transferred DNP-KLH or DNP-ASC-primed spleen cells produced high levels of anti-DNP antibodies of both IgE and IgG antibody classes in response to challenge with the appropriate homologous priming conjugate but failed to develop more than meager responses to the reciprocal heterologous conjugate. However, when spleen cells from donors primed to the second carrier were concomitantly transferred with hapten-primed lymphocytes, secondary IgE ant-DNP responses were consistently obtained upon challenge with the heterologous conjugate. Moreover, we have been able to elicit augmented primary IgE anti-DNP antibody responses to either DNP-ASC or DNP-KLH after adoptive transfer of spleen cells from donors primed only to the carrier, ASC or KLH, respectively. This adoptive transfer system has enabled us to provide direct proof for the participation of theta-bearing T lymphocytes in antibody responses of the IgE class. Thus, the capacity of ASC-primed spleen cells to effectively cooperate with the DNP-KLH-primed lymphocytes in the adoptive secondary response to DNP-ASC could be abolished by in vitro treatment of such cells with anti-theta serum plus complement. This was true not only for the anti-DNP response of the IgG antibody class, but for the IgE antibody class as well. These studies have, furthermore, demonstrated the capacity to stimulate secondary anti-DNP antibody production in vivo by the concomitant administration of the DNP and relevant carrier determinants on separate molecules. This was more readily seen in the IgE than in the IgG antibody class. Thus, DNP-ASC-primed cells developed significant IgE, but more variable IgG, anti-DNP responses upon challenge with DNP-KLH plus unconjugated ASC. Antibody responses of both classes elicited in this manner were appreciably improved by the transfer of additional carrier (ASC)-primed cells. These and other results presented herein suggest that IgE B lymphocyte precursors may be inherently more sensitive than IgG B cells to at least certain of the functions of T lymphocytes concerned with regulatory mechanisms involved in antibody production.

Adjuvants, Immunologic↗

PubMed1973

Cell interactions between histoincompatible T and B lymphocytes. IV. Involvement of the immune response (Ir) gene in the control of lymphocyte interactions in responses controlled by the gene.

In the present study we have asked the question of whether F(1) carrier-primed T cells can serve as helper cells for either or both parental B cells when (a) the carrier molecule employed is under genetic control such that one parental strain is a responder and the other is a nonresponder, and (b) the determinant specificity of the parental B cells being assessed is not under genetic control and bears no relationship to the specificity of the carrier molecule. Utilizing the system of immune response gene control of responses to the terpolymer L-glutamic acid-L-lysine-L-tyrosine (GLT) to which A strain mice (H-2(a)) are nonresponders, whereas BALB/c (H-2(d)) and (BALB/c x A)F(1) hybrids (CAF(1)) are responders, these studies demonstrate that GLT-primed T cells of CAF(1) donors can provide for responder BALB/c, but not for nonresponder A/J, the required stimulus for the anti-DNP responses of DNP-specific B cells of these respective parental strains to the DNP conjugate of GLT. The implications of these findings for Ir gene function in physiologic T-B cell interactions are discussed in detail.

Animals↗