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C S David

Publications and source records attributed to C S David.

At least 19 recordsLinked to original sources
PubMed1979

Regulatory mechanisms in cell-mediated immune responses. VIII. Differential expression of I-region determinants by suppressor cells and their targets in suppression of mixed leukocyte reactions.

The phenotypic expression of I-region determinants on cells producing and responding to MLR suppressor factor (MLR-TsF) was established in these studies. Alloantigen-activated MLR suppressor T cells (MLR-Ts), which produce MLR-TsF bearing gene products of the I-C subregion, were exposed to anti-I subregion sera and complement (C) before in vitro culture for MLR-TsF production. Suppressor activity was prevented by removal of cells bearing I-C determinants, whereas elimination of cells expressing I-A/B determinants had no effect. Interestingly, cytotoxic elimination of cells displaying I-J determinants also prevented MLR-TsF production. Admixture of anti-I-J and I-C antiserum-treated cells for MLR-TsF production failed to reconstitute suppressor activity, indicating that I-C and I-J gene products are expressed on a single population of cells critical to MLR suppression, rather than on distinct interacting subpopulations. Anti-I-C serum activity specific for I-C+ MLR-Ts was removed by adsorption with nylon wool-nonadherent splenic T cells and concanavalin A-activated thymocytes; adsorption with splenic B cells from anti-Thy-1,2 serum and C-treated spleen failed to remove relevant anti-I-C activity. These data suggest that regulatory I-C molecules, like I-J molecules, are preferentially expressed on T lymphocytes. Expression of I-C, or other I-region molecules on responder cell targets of MLR-TsF activity was also investigated. Responder cells were pretreated with anti-I subregion-specific sera in blocking or complement-dependent cytotoxic protocols before addition to MLR with MLR-TsF. Neither blocking nor the cytotoxic removal of cells bearing I-C or other I-region determinants from MLR responder populations interfered with MLR-TsF suppression. Because it has previously been demonstrated that MLR-TsF interacts optimally with activated, I-C syngeneic target cells, blocking and cytotoxic studies with anti-I subregion sera were also performed with responder cells activated by 24 h culture in MLR in the absence of MLR-TsF. Brief MLR-TsF pulse after antiserum treatment generated marked suppression regardless of blocking or absence of cells bearing serologically detected I-region determinants. I-C restricted suppression may thus be mediated not by interaction with I-C-bearing cells, but by target cells which exist in requisite association with populations of I-C+ cells.

Animals↗
PubMed1979

Regulatory mechanisms in cell-mediated immune responses. VII. Presence of I-C subregion determinants on mixed leukocyte reaction suppressor factor.

The presence of H-2 gene products on mixed leukocyte reaction (MLR) supressor factor was investigated by passage of MLR-suppressor factor (SF) over solid immunoadsorbents prepared with various anti-H-2 subregion sera. Antisera with specificity for all or certain I subregion determinants removed or significantly reduced suppressor activity; adsorption was not consistent with K or D region specificity. The single I subregion specificity common to all adsorbing preparations was I-C. Serologic differentiation of I-C products of k and d haplotypes expressed on MLR-SF was established with antisera prepared in I-Cd/I-Ck disparate strain combinations. These sera define allelic T cell restricted Lad determinants encoded by I-C genes. MLR-SF prepared from (BALB/c X CBA)F1 mice and exposed to the I-Cd and I-Ck specific adsorbents demonstrated d and k haplotype specific adsorption respectively. F1 suppressor activity adsorbed on an anti-I-Cd column was eluted by glycine-HCl buffer and suppressed only BALB/c (H-2d) responses. B10.A suppressor activity was removed by anti-I-Cd sera, but was unaffected by anti-I-Ck sera, indicating that B10.A suppressor activity is encoded by an I-C subregion derived from the d haplotype. Antisera with anti-I-Jk specificity did not remove suppressor activity of various H-2k factors. Finally, adsorption with antisera directed against H-2-associated determinants of the allogeneic cell used to stimulate suppressor factor generation demonstrated that sensitizing alloantigens are not components of MLR suppressor factor. Thus among the major histocompatibility complex (MHC)-controlled suppressor factors, MLR suppressor factor is uniquely determined by the I-C subregion.

Animals↗
PubMed1979

Serological analysis of antigen-specific helper factors specific for poly-L(Tyr, Glu)-poly-DLAla--poly-LLys [(T, G)-A--L] and L Glu60-LAla30-LTyr10 (GAT).

In vitro prepared antigen-specific helper factors reactive to the synthetic polypeptide antigens poly-L(Tyr, Glu)-poly-DLAla--poly-LLys [(T, G)-A--L] or LGlu60-LAla30-LTyr10 (GAT) and bearing Ia determinants were analyzed serologically to determine the nature of the Ia determinants they expressed. I subregion-specific mouse anti-Ia antisera were used, and showed that (T, G)-A--L-specific helper factor (HF) contains I-A subregion-controlled determinants, whereas GAT-specific HF carries I-J subregion-controlled antigens. This unexptected finding was confirmed in both the H-2k and H-2 b haplotypes, using a variety of anti-I-J antisera. Rabbit anti-Ia antisera also reacted with both HF which raised the possibility that the Ia determinants on HF may be carbohydrate in nature. The fact that HF has a low molecular weight and yet contains Ia determinants, antigen-binding capacity and idiotypic markers is compatible with this interpretation.

Adsorption↗
PubMed1979

Differences in the susceptibility of MHC and non-MHC mixed lymphocyte reactions to suppression by murine amnionic fluid and its components.

The ability of mouse amniotic fluid (MAF), alpha-foetoprotein (AFP) and MAF depleted of AFP (MAF - AFP) to suppress primary one-way MLR's was investigated. It was found that MAF, AFP and MAF - AFP were all suppressive of MLR's specific for MHC, K, D or I + S determinants. Suppression was observed when either lymph node or spleen cells were used as the responder cells. Nylon wool column passage of these cells did not significantly affect the immunosuppressive action of these substances. In contrast, MLR's specific for non-MHC/M-locus determinants demonstrated either diminished suppression or augmentation of the response, compared with the MHC stimulated MLR's. Our results show a differential effect of whole MAF and its fractions on the proliferative responses induced by various allogeneic stimuli and suggest that suppression is not due to a non-specific effect on proliferation regardless of the stimulus or cell type involved.

Amniotic Fluid↗
PubMed1979

Genetic control of the immune response to hen's egg-white lysozyme in mice. I. Antibody and T-lymphocyte proliferative responses to the native protein.

We have initiated studies to determine whether the antibody and T-lymphocyte proliferative responses to lysozyme and its antigenic sites is genetically controlled in mice. Mice of the H-2f, H-2k and H-2p were high responders, while haplotypes H-2b, H-2d, H-2r and H-2s were low responders. Studies with recombinants indicated that the immune response is controlled by two H-2I region loci, one being in the I-A subregion and the other may be in the I-C subregions.

Animals↗
PubMed1979

Regulation of autoimmune response to mouse thyroglobulin: influence of H-2D-end genes.

Studies were initiated to define the H-2-linked genetic control of response to self-determinants of MTg. In addition to the Ir gene control of H-2K end, a modifying effect of D end was seen. The extent of regulation depended upon the derivation of the K-end Ir-Tg gene(s) as well as the D-end genes. When the Ir-Tg gene was from good responder H-2k and H-Ss strains, and the H-2D-end gene from the d allele, antibody levels were moderate to high but cellular infiltration was significantly reduced. These findings demonstrate genetic interaction between I-region and D-end gene products in the response to a self-antigen, MTg.

Alleles↗
PubMed1979

Genetic control of immune response to sperm whale myoglobin in mice. II. T lymphocyte proliferative response to the synthetic antigenic sites.

The genetic control of T lymphocyte proliferative response to the five synthetic antigenic sites of myoglobin, two synthetic nonantigenic control peptides, and one "nonsense" peptide was determined in independent and recombinant strains of mice. In all the strains examined, the nonantigenic control peptides and the "nonsense" peptide did not invoke a response in myoglobin-primed mice. Further, when mice were not primed with whole myoglobin, no response was obtained with any of the antigenic sites. Haplotypes H-2d, H-2f, and H-2s are higher responders to sites 1 and 2, whereas haplotypes H-2d and H-2s are high responders to site 5. Response to site 3 may be controlled by a non-H-2-linked gene. Site 4 can stimulate H-2b and H-2k haplotypes that are nonresponders to the whole myoglobin. Studies with the recombinant strains suggested that Ir genes to sites 1 and 2 map in the I-A subregion and I-C subregion and were designated Ir-Mb-1,2(A) and Ir-Mb-1,2(C). Ir genes to sites 4 and 5 mapped only in the I-A subregion and were designated Ir-Mb-4(A) and Ir-Mb-5(A). These studies suggest that individual antigenic sites in a molecule are controlled by unique Ir genes.

Animals↗
PubMed1978

A new lymphocyte-activating determinant locus expressed on T cells, and mapping in I-C subregion.

A new lymphocyte-activating determinant (Lad) locus expressed on T cells was identified, mapping in the I-C subregions of H-2k and H-2d haplotypes. The mixed lymphocyte reaction stimulation could be inhibited by anti-Ia sera made in strains incompatible for this chromosomal segment. Experiments with purified lymphocyte cell populations suggested that this Lad locus was expressed on T cells. Further, only purified T cells were able to remove the inhibiting activity from the anti-Ia sera. I-C subregion gene(s) seem to code for products selectively expressed on a subpopulation of T cells.

Animals↗
PubMed1978

Inhibition of dual Ir gene-controlled T-lymphocyte proliferative response to poly (Glu56Lys35Phe9)n with anti-Ia antisera directed against products of either I-A or I-C subregion.

Previous studies have demonstrated that both the antibody and T-lymphocyte proliferative immune responses to poly(Glu53Lys36Phe11)n (GLphi) are under the control of two major histocompatibility-linked immune response (Ir) genes. One gene, termed Ir-GL phi-alpha, has been mapped to the I-C or I-E subregion of the major histocompatibility complex, while the other, termed Ir-GL phi-beta, has been mapped to the I-A subregion. In this paper we examine the effect of anti-I-region-associated (Ia) antisera on the T-lyphocyte proliferative response to GL phi. Antibodies directed against Ia antigens coded for by genes in either the I-A or I-C subregion were found to inhibit the proliferative response to GLphi. These results suggest that a function mediated by two Ir gene products can be blocked by anit-Ia antisera directed against either one, and thus, that both products are expressed on the cell surface.

Animals↗
PubMed1978

Immune response-associated antigens on mouse leukemia cells. II. Anti-Ia sera inhibit the MLR reaction between normal GR spleen cells and syngeneic spleen cells of GRSL tumor-bearing mice.

Mitomycin C-treated ascites cells of Ia antigen-positive GRSL14 tumor cells and spleen cells from GRSL14 tumor-bearing mice stimulated lymphocyte proliferative responses in normal syngeneic GR spleen cells. Furthermore, mitomycin C-treated T cells purified from spleen cells of tumor-bearing mice also stimulated normal GR spleen cells. Anti-Ia sera inhibited the stimulating ability of tumor cells and of spleen cells of tumor-bearing mice. These data suggest a role for I region gene products in immune surveillance for syngeneic tumors.

Animals↗
PubMed1978

Murine Ia antigens: identification and mapping of Ia.23 and further definition of the I-E subregion.

The Ia.23 specificity is a private specificity of the H-2d haplotype which we have assigned to the I-E subregion. It is found on the same Ia molecule that bears Ia.7, a public specificity previously assigned to the I-C subregion of haplotypes H-2d, H-2k, H-2p and H-2r. We suggest a reassignment of specificity Ia.7 to the I-E subregion to simplify the interpretation of the data presented in this paper and elsewhere, and to permit an orderly description of that part of the I region to the right of I-J.

Animals↗
PubMed1978

Structural studies of the protein portion of the H-2-linked Ia glycoprotein antigens of the mouse: tryptic peptide comparison of products from the I-A and I-C subregions of B10-HTT.

Ia antigens from the I-A8 and I-Ck subregions of the B10.HTT (H-2t3) strain of mice were isolated by indirect immunoprecipitation of arginine-labeled, nonionic detergent-solubilized materials. After biochemical purification the electrophoretically homogeneous 28,000 dalton glycoprotein beta chains from the Ia precipitates were digested with trypsin and the resultant radiolabeled tryptic peptides were compared by analytical ion exchange chromatography. These comparisons reveal that the beta chains of Ia antigens from the A (I-A8) and C (I-Ck) subregions of B10.HTT share only two out of 12 to 14 of their arginine tryptic peptides. Thus these noncross-reactive Ia antigens are structurally quite diverse, and would possess sufficient structural variability to account for their lack of antigenic cross-reactivity.

Amino Acids↗
PubMed1978

Genetic control of immune response to sperm whale myoglobin in mice. I. T lymphocyte proliferative response under H-2-linked Ir gene control.

Studies on the genetic control of immune response to sperm whale myoglobin were initiated. As demonstrated in this paper, the T lymphocyte proliferative response to whale myoglobin is under H-2-linked Ir gene control. Mice of H-2d, H-2f, and H-2s haplotypes were high responders to the myoglobin, whereas haplotypes H-2b, H-2k, H-2p, H-2q, and H-2r were low responders. The Ir gene(s) was localized between H-2K and H2D regions, since the recombinant strain A.TL (KsIkSkDd) was a low responder and A.TH (KsIsSsDd) was a high responder. Further studies with recombinant strains revealed that the expression of the high-responder I-Ad or Ias alleles was sufficient to give a good response, since strains D2.GD (d d b b b b b b) and B10.HTT (s s s s k k k d) were high responders. The expression of the I-Cd allele in strains B10.A (k k k k k d d d) and B10.A(5R) (b b b k k d d d) also gave high response, and thus suggested a second Ir gene, derived from the H-2d haplotype. The finding that expression of the I-Cs allele in B10.S(8R) (k k ? ? s s s s) did not result in high response suggests the lack of the second Ir gene in the high-responder H-2s haplotype.

Animals↗
PubMed1977

The role of gene products of the I-J subregion in mixed lymphocyte reactions.

We have examined the MLR reaction in two sets of recombinants that differ in the I-J subregion. In both cases, significant stimulation was mediated by antigens controlled by genes in the I-J subregion. This stimulation was inhibitable by the addition of the culture of antisera directed against the I-J gene products on the stimulator cell. The specificity of this inhibition was shown by specific blocking of the relevant gene product on F1 hybrid stimulator cells. MLR stimulation was also eliminated by pretreatment of the stimulator population with anti-I-J sera plus complement. Pretreatment of F1 hybrid stimulator T cells with anti-I-J sera directed against either parental I-J product in the presence of complement, completely eliminated stimulation, indicating that there is no allelic exclusion of the relevant I-J products. Pretreatment with an anti-I-E/I-C serum and complement also eliminated stimulation, suggesting that the stimulating T cells express both I-J and I-E/I-C subregion products. This assay offers a potentially more direct and practical method for serological detection of the I-J products.

Animals↗
PubMed1977

Properties of reticulum cell sarcomas in SJL/J mice. V. Nature of reticulum cell sarcoma surface antigen which induces proliferation of normal SJL/J T cells.

The results of studies on the reticulum cell sarcoma (RCS) tumors of SJL/J mice presented here, indicate that spontaneous tumors, which arise in older mice, also possess the capacity to induce the vigorous proliferative response in syngenetic T lymphocytes that are characteristic of the transplantable RCS lines. Analysis of cell surface antigens revealed the presence of Ia determinats on gradient-purified transplantable RCS tumor cells; however, these cells did not express Thy 1.2, nIg, or, any of the viral proteins that were tested for by specific antisera. Pretreatment of RCS cells with anti-Ia sera and complement-deleted cells that were stimulatory for syngenetic T lymphocytes, and addition of anti-Ia sera directly to cultures blocked the proliferative response at the stimulator (RCS) cell level. Lymph node cells from H-2(8) strains other than SJL/J, including A.SW and B10.S also gave proliferative responses to RCS cells, although lower in magnitude. A requirement on the part of responding cells for identity with RCS cells at the Ir region was indicated by the finding that A.TH but not A.TL lymph node cells responded to RCS. It is concluded that RCS cells stimulate Ir-region identical T cells (without evidence of presensitization) through a modification in the expression of Ia antigens on the surface of the tumor cells.

Animals↗