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J A Frelinger

Publications and source records attributed to J A Frelinger.

At least 145 records · Page 8Linked to original sources
PubMed1979

Immunochemical characterization of the Ly-8.2 murine lymphocyte alloantigen: possible relationship to actin.

An immunochemical analysis of the Ly-8.2 antigen was performed. Reactivity of B10-radiolabeled T and B cell lysates with a C3H anti-AKR serum immunoprecipitates a major 43,000 m.w. protein detectable by one-dimensional gel electrophoresis. The protein can be radioiodinated, however, it does not appear to blind to lentil lectin. Two-dimensional gel electro phoresis and peptide-mapping studies indicate that this protein is structurally very similar to lymphocyte actin. The possible molecular relationship between Ly-8.2, other lymphocyte membrane antigens, and actin is discussed.

Actins↗
PubMed1978

T-lymphocyte response to H-2 mutants. I. Proliferation is dependent on Ly 1+2+ cells.

We have determined the Ly phenotype of the T lymphocytes which proliferate in response to mutant H-2K and H-2D alloantigens in primary mixed lymphocyte culture. Responder T cells proliferating in reciprocal cultures of H-2d(KdDd) and H-2da(KdDda) lymphocytes were typed Ly 2+ through selective depletion with specific alloantiserum plus complement. Further, B6-Ly 1a lymphocytes proliferating in response to B6-H-2ba and B6-H-2bf stimulators were typed as Ly 1+2+ through similar analysis. These results are discussed with regard to their impact on views of lymphocyte differentiation and factors determining the identity of alloreactive lymphocytes.

Animals↗
PubMed1978

Murine Ia and human DR antigens: homology of amino-terminal sequences.

Murine Ia and human DR antigens were isolated and purified by immunoprecipitation and sodium dodecyl sulfate/polyacrylamide gel electrophoresis with allo- and xenoantisera, respectively. The I-A subregion antigen consists of two chains, designated Aalpha and Abeta, with molecular weights of 35,000 and 26,000, respectively. The I-C subregion antigen likewise consists of two chains, designated Calpha and Cbeta, with molecular weights of 32,000 and 29,000, respectively. Under nonreducing conditions, the Cbeta chain migrates appreciably more rapidly on sodium dodecyl sulfate/polyacrylamide gels than the reduced Cbeta chain, reflecting the presence of an intrachain disulfide bond. The human DR antigen is also a two-chain unit and contains DRalpha and DRbeta components with molecular weights of 34,000 and 28,000, respectively. The DRbeta chain migrates more rapidly before reduction than afterward, like the murine Cbeta chain. The DRbeta and Cbeta chains are also strikingly homologous if a single amino acid shift is imposed on one of those chains. Thus, human DR antigens strongly resemble the murine I-C subregion antigens.

Amino Acid Sequence↗
PubMed1978

Expression of I-A and I-E,C region-coded Ia antigens on functional B cell subpopulations.

Ia antigens from specific subregions have been examined on functional B cell populations. Expression of both I-A and I-E,C region antigens was demonstrated on cells required for both lipopolysaccharide mitogenesis and polyclonal activation. Similar I-A and I-E,C subregion expression was found on cells required for response to the T-independent antigen, polyvinylpyrrolidone. TNP-specific IgM and hen egg lysozyme-specific IgG plaque-forming cells also express I-A and I-E,C region antigens. No evidence was found for an Ia- population responsive in the systems tested. Further, no evidence of preferential expression of I-A or I-E,C region antigens was observed in any system examined. Therefore, it appears that B cells express both I-A and I-E,C region-coded Ia antigens.

Animals↗
PubMed1977

H-2 effects on cell-cell interactions in the response to single non-H-2 alloantigens. I. Donor H-2D region control of H-7.1-immunogenicity and lack of restriction in vivo.

Genes in the H-2 complex regulate the relative immunogenicity of the H-7.1 histocompatibility alloantigen, as measured by survival times of H-7.1-incompatible skin grafts in vivo. The gene controlling relative rejectability of H-7.1-incompatible grafts has been mapped to the H-2D region. H-7.1-incompatible skin grafts donated by H-2Db donors were rejected significantly more rapidly by H-2a/H-2b heterozygous recipients than similar H-7.1-incompatible grafts donated by H-2Dd donors. Further, there was absolutely no evidence of H-2 restriction in cytotoxic effector activity. In vivo cross-priming, as indicated by accelerated secondary graft rejection, was extensive. The efficiency of cross-priming was dependent upon the primary and secondary graft donor H-2 haplotypes.

Animals↗
PubMed1977

H-2 effects on cell-cell interactions in the response to single non-H-2 alloantigens. II. H-2D region control of H-7.1-specific stimulator function in mixed lymphocyte culture and susceptibility to lysis by H-7.1-specific cytotoxic cells.

The relative immunogenicity of the H-7.1 alloantigen has been shown in a previous communication to be regulated by a gene in the D region of the mouse major histocompatibility (H-2) complex. The level of relative immunogenicity was inferred from survival times of H-7.1-incompatible skin grafts donated by donors with different H-2 haplotype origins of H-2D region genes. In this communication we report the results of an extension of these previous investigations into the possible role of H-2D region genes in controlling the capacity of H-7.1-incompatible lymphocytes to stimulate H-7.1-speciflc mixed lymphocyte culture proliferation and generation of cytotoxic effector cells. The results reported herein demonstrate that the H-2D genotype of H-7.1-incompatible stimulator cells determines the relative H-7.1-specific capacity of those lymphocytes to stimulate H-7.1-specific proliferation of in vivo primed responder T cells in secondary mixed lymphocyte culture. H-2D(b)-bearing, H-7.l-incompatible stimulators were significantly more effective in stimulating H-7.1-specific proliferation than H-2D(d)-bearing stimulators. As expected, H-2D(b), H-7.1-in-compatible stimulators were also more effective than H-2D(d) a stimulators in generating H-7.1- specific cytotoxic effector cells. Further, the susceptibility of (51)Cr- labeled, H-7.1-incompatible lymphoblast targets to H-7.1-specific lysis was similarly regulated by an H-2D gene. Reciprocal H-2 restriction (F(1) cells are capable of killing only the cells bearing the immunizing cell parental H-2 haplotype) observed by other investigators for cytolysis of non-H-2-incompatible targets was not observed. H-2D a-bearing, H-7.1- incompatible stimulators stimulated generation of cytotoxic effectors capable of detectably lysing H-2D(b) but not H-2D(a)-bearing, H-7.1- incompatible targets. The impact of these observations on the proposed models for H-2 restriction of non-H-2 histocompatibility antigen-specific cytolysis is discussed.

Animals↗
PubMed1977

Immune mechanisms in leukemia role of the Ia antigens.

We have shown that the selective removal of cells possessing Ia determinants coded by the I-A, I-B, and I-J regions of the H-2 gene complex completely abrogates the protective capacity of nylon-wool-purified T lymphocytes against leukemic challenge. This suggests that the Ia antigen bearing T cells play an important role in tumor immunity.

Animals↗
PubMed1977

Ia-bearing cells promote the concanavalin A mitogenic response of Ia-negative T cells.

Nylon wool column-purified T cell populations depleted of Ia-bearing cells do not respond to the T cell mitogen concanavalin A (Con A). The response of this population can be restored by admixture of untreated nylon wool-nonadherent T cells. These promotor cells express Thy-1, are not sensitive to mitomycin C treatment and cannot be replaced with adherent spleen cells. Experiments using the T6 chromosome marker demonstrate that Ia-depleted populations respond to ConA only in the presence of the Ia-positive population.

Animals↗
PubMed1977

Chemical characterization of murine Ia alloantigens determined by the i-E/i-C subregions of the H-2 complex.

Alloantisera directed against the alloantigens determined by the I-E and I-C subregions of the murine major histocompatibility complex precipitate two components that have molecular weights of 35,000 and 29,000. These components, when analyzed by partial NH2-terminal sequencing, show no homology to two components of similar size determined by the I-A subregion. However, the large chain determined by the murine I-E and/or I-C subregion is homologous to the large chain of the human HLA-D region alloantigen, although the small chains isolated from these two species do not display any such homology.

Amino Acid Sequence↗
PubMed1976

Effects of anti-Ia sera on mitogenic responses. III. Mapping the genes controlling the expression of Ia determinants on concanavalin A-reactive cells to the I-J subregion of the H-2 gene complex.

We have shown that the Ia determinants expressed on nylon wool-purified T lymphocytes reactive to concanavalin A (Con A) in serum-free media are coded in a single I subregion of the H-2 gene complex. This region, I-J, is defined by two pairs of intra-H-2 recombinant haplotypes: H-2t3, H-2t4 and H-2i3, H-2i5, carried by B10.HTT, B10.S(9R), B10.A(3R), AND B10.A(5R), respectively. No activity against Con A-reactive T cells has been detected in any antiserum that was produced in strain combinations which shared a common I-J region. This suggests that Ia antigens expressed on Con A-reactive T cells are restricted to the I-J subregion.

Animals↗
PubMed1976

Effects of anti-Ia sera on mitogenic responses. II. Differential expression of the Ia marker on phytohemagglutinin and concanavalin A-reactive T cells.

Genes mapping in the I region of the H-2 complex control a system of lymphocyte alloantigens (Ia) which are expressed on a subpopulation of T cells and on most B cells. Specific anti-Ia serum in the presence of rabbit complement removed the splenic T-cell subpopulation responsive to Con-A, but did not affect the response to phytohemagglutinin (PHA) or Leucoagglutinin. Antibodies specific for Ia, H-2K, or H-2D membrane antigens were used without complement to pretreat spleen cells. These antibody pretreated cells responded normally to Con-A and PHA.

Animals↗
PubMed1975

Inhibition of immune responses in vitro by specific antiserums to Ia antigens.

Mouse antiserums prepared against Ia antigens, which are products of I (immune response) region genes of the H-2 complex, can inhibit both primary (immunoglobulin M) and secondary (immunoglobulin G) immune responses in vitro by mouse spleen cultures to heterologous erythrocytes. Antiserums directed specifically at products of either the H-2K or H-2D loci have no effect on this response.

Animals↗