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C G Fathman

Publications and source records attributed to C G Fathman.

At least 163 records · Page 9Linked to original sources
PubMed1982

Abnormal migration of T lymphocyte clones.

Several in vitro T cell clones were markedly deficient in their ability to home to peripheral lymphoid tissue. This was found for an alloreactive noncytolytic clone, a soluble antigen- (KLH)specific line, and cytotoxic clones specific for allogeneic cells and for Abelson virus-induced lymphoma cells. This abnormal circulation pattern was probably caused by the lack of the receptors of the lymphocytes for high endothelial venules (HEV), as implied by the lack of binding of these T cells to HEV in frozen sections of mouse lymph node and Peyer's patches. The loss of surface receptors that are necessary for normal lymphocyte migration may thereby alter the in vivo function of adoptively transferred T cells.

Animals↗
PubMed1981

T cell clones reactive with sperm whale myoglobin. Isolation of clones with specificity for individual determinants on myoglobin.

We have been able to isolate clones of sperm whale muscle myoglobin (Mb)-reactive T cells from (C57BL/6 x A/J)F1 [(B6A)F1] mice. Four types of clones were isolated, distinguished by their patterns of recognition of Mb cyanogen bromide (CNBr) fragments and antigen presenting cell (APC) requirements. Individual T cell clones proliferated in response to one of three CNBr fragments of Mb. Dose-response curves of all clones were identical for native Mb and the appropriate fragment. T cell clones reactive to fragment 1-55 did not proliferate in response to peptide 15-22 (a peptide that binds to serum antibody directed against 1-55). These data support previous findings suggesting differences between antigen recognition by T and B cells, i.e., T cells may not recognize antigen in its native conformation and/or T and B cells may recognize distinct epitopes on the same antigen. Using T cell clones to analyze genetic control of responsiveness to Mb, we found that certain (B6A)F1 T cells recognize Mb presented by low responder strain APC. Thus, genetically determined low responsiveness in this case is probably not due to failure of APC function. We also found that responsiveness to certain Mb epitopes mapped to the I-A subregion whereas others mapped, via gene complementation, to the I-A and I-E subregions. We found no examples of responsiveness mapping to the I-C subregion and suggest an alternative explanation for previous reports mapping genetic control of responsiveness to certain Mb determinants to I-C.

Animals↗
PubMed1981

Major histocompatibility complex-restricted antigen presentation to antigen-reactive T cells by B lymphocyte tumor cells.

Previous reports have demonstrated that accessory cells function to present soluble protein antigens in association with gene products encoded within the I region of the major histocompatibility complex (MHC) to antigen-reactive T helper cells. The biochemical events that occur during antigen presentation are, however, not well-documented primarily because of the difficulties involved in purifying sufficient numbers of homogeneous antigen-presenting cells. In this paper, a number of Ia-positive B lymphocyte tumor lines are shown to be capable of presenting soluble protein antigens to antigen-reactive continuous T cell lines in an MHC-restricted fashion. The characterization of the antigen presentation function of these tumor cells indicates that the tumor cells have many of the functional antigen-presenting characteristics previously thought to be limited to macrophages. These tumor cells should provide a useful model system for determining the biochemical events that occur in antigen uptake and processing as well as for determining the potential interactions between processed antigen and Ia molecules on the plasma membrane of these antigen-presenting cells.

Animals↗
PubMed1981

Antigen-reactive T clones. III. Low responder antigen-presenting cells function effectively to present antigen to selected T cell clones derived from (High Responder x Low Responder)F1 mice.

Long-term-cultured poly(Tyr, Glu)-poly-D,L,-Ala-poly-Lys [(T,G)-A--L]-reactive T cells and clones derived from (high responder x low responder)F1 [(C57BL/6 x A/J)F1] mice were shown to recognize (T,G)-A--L presented by cells from low responder strain A/J mice. The antigen-presenting determinant(s) that allowed recognition of (T,G)-A--L by such T cell clones was controlled by the I-A subregion of the major histocompatibility complex. These results suggest that there is no functional defect in the ability of low responder Ir gene products (I-A antigens) to associate with (T,G)-A--L for effective recognition by T cells. Although these results might tentatively be interpreted to suggest that Ir gene-controlled low responsiveness is due to the inability of the T cell to recognize the association between (T,G)-A--L and low responder I-A gene products, it is similarly possible that there might be a defect in the functional capabilities of low responder antigen-presenting cells to effectively process (T,G)-A--L into immunodominant epitopes.

Animals↗
PubMed1981

Antigen-reactive T cell clones. II. Unique homozygous and (high responder x low responder)F1 hybrid antigen-presenting determinants detected using poly(Tyr, Glu)-poly D, L-Ala--poly Lys-reactive T cell clones.

Using murine (T,G)-A--L-reactive T cell clones, we have demonstrated the existence of unique homozygous antigen-presenting determinants expressed on C57bl/6 mice, controlled by the I-A subregion of the murine major histocompatibility complex (MHC), which are not expressed on semisyngeneic (C57Bl/6 x A/J)F1 [(B6A)F1] cells. Additionally, we were able to demonstrate that there exist (T,G)-A--L-reactive clones in F1 mice derived between low responder and high responder parents [(B6A)F1] that recognize antigen in association with transcomplementing hybrid I-A subregion determinants expressed uniquely on (B6A)F1 cells not expressed on cells of either of the parental strains. These data suggest that phenotypic high responsiveness exhibited by (higher responder x low responder)F1 mice was not simply controlled by the high responder parental genome, but was controlled at the phenotypic level of expression of antigen-presenting determinants. Such antigen-presenting determinants can be created by complementation using products of the low responder as well as high responder genome. The significance of the existence of such F1 specific hybrid antigen-presenting determinants for T cell specificity and recognition of self was discussed.

Animals↗
PubMed1981

I-region genetic restrictions imposed upon the recognition of KLH by murine T-cell clones.

Data presented in this paper show that the recognition of keyhole limpet hemocyanin by murine T-cell clones is restricted by products of the I region. These data have been obtained by genetic mapping studies as well as by the use of monoclonal Ia-specific antibodies which inhibit the ability of antigen-presenting cells to effectively present antigen to such T- cell clones. Use of heterozygous antigen-presenting cells derived from crosses between B6.C-H-2bm12 and B10.A(4R) mice have allowed us to show that both trans-complementing I-A products are used for restriction of recognition of KLH. These data were confirmed using monoclonal Ia antibodies to inhibition recognition of KLH by the same T -cell clones. Thus, we have shown that there exist hybrid molecules formed by free combinatorial association of products encoded within the I-A subregion which restrict the recognition of soluble antigen. Additionally, we have shown that the molecule formed by complementation between the alpha chain encoded within the I-E region and a beta chain encoded within the A region (Ae) can fuction effectively in presenting KLH to certain murine T -cell clones. These results support the hypothesis that the recognition of individual antigenic epitopes within large multideterminant antigens is under the control of Ir genes.

Animals↗
PubMed1981

Functional helper activity of monoclonal T cell populations: antigen-specific and H-2 restricted cloned T cells provide help for in vitro antibody responses to trinitrophenyl-poly(LTyr,Glu)-poly(DLAla)--poly(LLys).

The ability of long-term cultured and monoclonal T cell populations to provide antigen-specific help was assessed in a system of Ir gene-controlled in vitro antibody responses to soluble antigens. T-cell colonies and monoclonal T-cell lines were generated which proliferated specifically in response to poly(LTyr,Glu)-poly(DLAla)--poly(LLys) [(T,G)-A--L] and were I-A restricted in these proliferative responses. These (T,G)-A--L-specific T-cell populations were evaluated for their ability to help unprimed and T-cell depleted spleen cell populations in the generation of antibody responses to trinitrophenyl (TNP)-(T,G)-A--L in vitro. It was found that long-term T-cell lines, including monoclonal T-cell populations derived by limiting dilution, were highly efficient helper cells for IgM responses to TNP-(T,G)-A--L. These helper T cells were both antigen-specific and I-A restricted in their ability to be activated and to cooperate with T-cell depleted spleen cell populations. Once specifically activated, however, these clones provided help that was antigen nonspecific. These studies have thus demonstrated the ability of antigen-specific and H-2-restricted monoclonal T-cell populations to provide help for responses to soluble antigens in vitro.

Animals↗
PubMed1981

Reconstitution of Ir genes, Ia antigens, and mixed lymphocyte reaction determinants by gene complementation.

By using clones of murine T cells reactive with alloantigens as well as soluble antigens, it has been possible to demonstrate that Ia antigens, Ir gene phenomena (defined as the ability of immune T cells to recognize antigen), and mixed lymphocyte reaction (MLR)-stimulating determinants encoded within the I-A subregion are different manifestations associated with same product. These studies utilized the I-Ab mutant mouse B6.C-H-2bm (bm12), whose defect in the normal expression of the cell surface products of the I-Ab subregion can be partially circumvented through trans-complementation by deriving hybrids between bm12 and mice expressing normal I-A subregion products. Such mice [e.g., (bm12 X B10.A)F1] express several serologically normal I-Ab products but have defects in certain I-A subregion gene products normally expressed on cells of H-2a X H-2b heterozygote mice that are used as restricting elements for antigen recognition by antigen-reactive T cell clones or recognized as alloantigens by alloreactive T cell clones. This defect in cell surface expression of certain normal I-Ab products on the mutant bm12 cells has allowed us to suggest that there exist trans-complementing products on H-2a X H-2b heterozygote mice consisting of Ab alpha Ak beta and Ak alpha Ab beta that restrict antigen recognition by cloned T cells, stimulate MLR responses by cloned T cells, and react with certain anti-Ia antisera.

Animals↗
PubMed1980

Antigen-reactive T cell clones. I. Transcomplementing hybrid I-A-region gene products function effectively in antigen presentation.

Studies in our laboratory and elsewhere have shown that it is possible to propagate antigen-specific murine T cells in vitro with resultant specific stepwise enrichment of antigen-induced proliferative cells. The proliferative responses of these T cells are antigen specific and dependent upon the presence of antigen-presenting cells (spleen cells) that share the I-A subregion with the proliferating T cell. Using techniques of soft-agar cloning, it has been further possible to isolate clones of antigen-reactive T lymphocytes from such long-term cultures. Data suggesting that these were clones of antigen-reactive T cells were obtained by studying the recognition of antigen in association with antigen-presenting cells with a panel of such clones of antigen-reactive T cells. Proof of clonality was obtained by subcloning. Clones derived from F1-immune mice can be divided into three separate categories: one clone recognizes antigen in association with antigen-presenting determinants of parent A and the F1; the second type recognizes antigen in association with antigen-presenting determinants of parent B and the F1; and the third type recognizes antigen only in association with antigen-presenting determinants of the F1 mouse. Genetic studies on the major histocompatibility complex requirements for antigen presentation to such F1-reactive T cell clones suggests that the hybrid antigen-presenting determinant in this system results from transcomplementation of products of the I-A region of haplotypes a and b. These studies support the concept developed in our laboratory that there exist unique F1 hybrid determinants on (A/J X C57BL/6) F1 cells and suggest that these determinants can be utilized physiologically by hybrid mice in immunocompetent cellular interactions.

Animals↗
PubMed1980

Associations of antibodies to native DNA with HLA-DRw3. A possible major histocompatibility complex-linked human immune response gene.

We examined the incidence of B lymphocyte (HLA-DRw) alloantigens in patients who exhibited elevated antibody titers to native DNA irrespective of their diagnosis. We found a statistically significant (P less than or equal to 0.0001) association between HLA-DRw3 and the presence of antibodies to native DNA not only in patients with a diagnosis of systemic lupus erythematosus but in other patients who did not share that diagnosis. This association supports the existence of a human immune response gene linked to the HLA complex. These data suggest that the hypothesis of an association between HLA and disease operating through disease susceptibility antigens or genes might be invalid and supports an alternative hypothesis, that HLA and disease associations are a manifestation of an immune response gene that controls the production of specific antibodies in any of several disease states.

Antibody Formation↗
PubMed1980

Clones of alloreactive T cells. I. A. unique homozygous MLR-stimulating determinant present on B6 stimulators.

We have developed a method which allows us to clone and reclone primed responder T cells derived from serially restimulated murine mixed lymphocyte cultures. We have derived clones from two such mixed lymphocyte cultures, A anti-B6 [A(B6)] and A anti-(B6XA)F1 [A(B6A)]. In the A (B6) system, we have isolated clones which can ve stimulated by B6 but not by (B6XA)F1 cells. This implies the presence of a unique parental H-2b MLR determinant which is absent on semi-allogeneic (B6XA)F1 cells. In the A(B6A) system, we have isolated clones which can be stimulated by (B6XA)F1 cells but not by B6 cells. This confirms our previous observation on the presence of unique hybrid MLR stimulating determinants on (B6XA)F1 cells. Many of the "clones" derived primarily from soft agar seem to be contaminated and contain several different sets of primed responder cells with different reactivity patterns . Experiments in which we subclone cells exhibiting selected reactivity patterns from such contaminated primary clones suggested that a T-cell growth factor or accessory cell is required for proliferation in soft agar following all antigen recognition by primed responder cells.

Animals↗
PubMed1979

Crossreactive mixed lymphocyte reaction determinants recognized by cloned alloreactive T cells.

We have isolated clones of alloreactive T cells by soft agar cloning of primed responder cells contained in serially restimulated, mixed lymphocyte cultures. These clones recognize unique mixed lymphocyte reaction (MLR) stimulating determinants present on (C57B/6 X A/J)F1 (B6A) spleen cells. By assaying the reactivity patterns of these clones on a panel of stimulator cells, we have identified at least three separate "specificities" of alloreactive T cell clones. Several clones exhibiting one of these three reactivity patterns have been isolated on many occasions from different experiments. Using such clones of alloreactive T cells, we have identified and are attempting to define crossreactive MLR stimulating determinants exhibited by a panel of stimulator cells. Recognition by certain clones of a shared MLR determinant(s) on B6A and DBA/2 and of the lack of this determinant(s) on B6 stimulator cells questions current concepts concerning the nature of MLR stimulating determinants and T cell recognition of alloantigens.

Animals↗
PubMed1979

Non-H-2 linked control of low versus high responses of antigen-induced lymph node cell proliferation: possible role for antigen-presenting cells.

Quantitative differences in the magnitude of antigen-induced proliferative responses of sensitized lymph node cells between low (C3H/Anf or C3H/Cr) and high (C3H/Hej or CBA/j) responder H-2k mice have been observed 1 to 2 weeks after in vivo sensitization with antigen (OVA, PPD, and GAT). We have shown that antigen presentation is less effective in the sensitized lymph node cell populations from low responder mice compared with those from high responder mice, suggesting that the number and/or functional status of antigen-presenting cells in the regional lymph nodes may be a key factor in determining the magnitude of antigen-induced proliferative responses. These data are consistent with the hypothesis that cell traffic after sensitization plays an important role in determining the immune responsiveness of lymph nodes.

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