摘要:

AbstractTwo monoclonal antibodies, CT‐1 (IgG1,χ) and CT‐1a (IgG3,χ), were prepared against chicken thymocytes. The antigen identified by these antibodies was found to be a glycoprotein with a major polypeptide component having an apparent molecular weight of 63000 and a minor polypeptide component of approximately 103000. Immunoprecipitation and blocking experiments revealed that the two antibodies react with different antigenic determinants of the molecule. Ontogenic studies employing immunofluorescence failed to reveal the antigenic determinants on cells from the embryo or embryonic yolk sac on days 3 and 6 of incubation. The number of embryonic thymocytes bearing the molecules detected by these antibodies increased from 6% on day 12 to 54% on day 13; the frequency of thymocytes expressing this glycoprotein reached adult levels (>90%) by the 15th day of embryonic age. In contrast, the CT‐1 and CT‐1a antibodies reacted with only 2‐5% of blood and splenic cells and less than 0.05% of cells from bursa or bone marrow of young adult chickens. In the quail CT‐1 reacted with cortical, but not medullary, thymocytes, while the CT‐1a antibody was unreactive with quail thymocytes. The surface glycoproteins detected by these discriminating monoclonal antibodies may provide an important discriminating marker for thymic lymphocytes in the chicke

ISSN:0014-2980    

DOI:10.1002/eji.1830140502

出版商:WILEY‐VCH Verlag GmbH    

年代:1984

数据来源: WILEY

摘要:

AbstractThe surface membrane antigens of infectiousTrypanosoma cruzitrypomastigotes were studied at the levels of the strain and of individual trypomastigote clones. Blood trypomastigotes from threeT. cruzistrains, Y, CL and Tehuantepec (“Teh”), were grownin vitroby weekly infection of J774 mouse macrophage tumor cells. EachT. cruzistrain was subsequently cloned by infection of J774 cells at limited trypomastigote dilution, and antisera were produced in mice against a selection of trypomastigote clones. Criss‐cross panel analyses indicated the existence of a large degree of polymorphism among trypomastigote surface antigens. Various trypomastigote surface antigens were cross‐reactive, appeared to be highly conserved, and were common to the three strains considered and to all the clones derived from each strain. Analysis by sodium dodecyl sulfate polyacrylamide gel electrophoresis showed that numerous trypomastigote antigenic proteins were precipitated by mouse antisera generated against cloned trypomastigotes. Some of these proteins were commonly distributed, while others were polymorphic. Finally, a state of cross‐reactive immunity could be induced in C3H/He mice by infection with a clonedT. cruzitrypomastigote population. Immune mice resisted subsequent infections with lethal doses of wild‐type bloodstream trypomastigotes from any one of the threeT. c

ISSN:0014-2980    

DOI:10.1002/eji.1830140503

出版商:WILEY‐VCH Verlag GmbH    

年代:1984

数据来源: WILEY

摘要:

AbstractPeripheral blood lymphocytes from an individual, recently boosted with tetanus toxoid (TT), were transformed with Epstein‐Barr virus. No antigen‐specific selection nor stimulation of B cells was performed prior to transformation. One stable cell line, designated CLB‐Hu‐TT‐1, was established. This cell line has a doubling time of 24 h and yields 10 μg/ml of a monoclonal IgG1,χ anti‐TT antibody in bulk cultures. The antibody is biologically active in that it can protect mice against the effects of tetanus toxin. The cell line has been characterized with regard to some cytoplasmic and mem

ISSN:0014-2980    

DOI:10.1002/eji.1830140504

出版商:WILEY‐VCH Verlag GmbH    

年代:1984

数据来源: WILEY

摘要:

AbstractOver 300 monoclonal IgG alloantibodies have been prepared against RT1Aa, the class I major histocompatibility complex molecule of the DA rat. In this study a combination of techniques is exploited to show that all these antibodies can be allocated to 9 antigenic sites which form a continuous antigenic surface, that is, no site is completely isolated from the rest. The results suggest that techniques for the identification of antigenic sites using competitive inhibition of monoclonal antibody binding are generally valid, in the sense that competition between antibodies appears most commonly to represent competition between combining sites for a structural feature of the antigenic surface. From the distribution of antibodies between sites, it is clear that the RT1Aamolecule has three immunogenic areas against which nearly all the antibodies studied were directed. Of these areas one is both antigenically complex, consisting of four closely spaced sites, and remarkably immunodominant. Antibodies directed at sites between the major areas are extremely rare.

ISSN:0014-2980    

DOI:10.1002/eji.1830140505

出版商:WILEY‐VCH Verlag GmbH    

年代:1984

数据来源: WILEY

摘要:

AbstractHybridomas producing monoclonal antibodies (mAb) specific for immunoglobulin heavy chain (Igh) allotype‐linked gene products expressed only on functional T cells but not on B cells and macrophages were established by fusion of allotype congenic SJL (Igh‐1b) and SJA/9 (Igh‐1a) B cells immunized reciprocally with partner spleen cells with a myeloma P3‐X63‐Ag8‐653 of BALB/c origin. Nine mAb have been selected on the criteria that they can specifically block various antigen‐dependent functions of known T cell subsets inin vitroimmune responses of mouse strains having the corresponding Igh allotype, but not the other one. These included (a) four mAb that augment thein vitrosecondary antibody response of either Igh‐1aor Igh‐1bstrains and thus are considered to react with the Igh‐linked allotypic determinant expressed on suppressor T cells, (b) one mAb that inhibits the helper T cell activity of Igh‐1bbut not of Igh‐1astrains, (c) two mAb that inhibit the antigen‐induced pro‐liferative response of Igh‐1abut not Igh‐1bstrains, and (d) two mAb that block the cytotoxicity of alloreactive cytotoxic T cells of Igh‐1astrains. The linkage to Igh‐1 allotype of the T cell products was established by testing with Igh‐1‐congenic strains with different backgrounds including the H‐2 complex. Some of the mAb were able to react with cloned hybridomas and a continuous cell line of the given allotype and functions. Each mAb was able to block one of the known functions of T cell subsets, but not others, indicating the existence of the heterogeneity and multiplicity of th

ISSN:0014-2980    

DOI:10.1002/eji.1830140506

出版商:WILEY‐VCH Verlag GmbH    

年代:1984

数据来源: WILEY

摘要:

AbstractMigration and lodging properties of IgA cells and their precursors of the gut lamina propria (GLP) were studied by transfer of highly purified GLP lymphoid cells between immunoglobulin allotype‐congenic mice (CB‐20 to BALB/c). The donor IgA‐containing (cIgA) cells appeared in the GLP of the recipients at day 1, peaked at days 12–15 (late repopulation peak) and persisted up to day 20 after cell transfer. An additional peak at day 3 (early repopulation peak) was seen only when large numbers of GLP B cells were transferred. Few cIgA cells appearing in spleen and mesenteric lymph nodes were seen mainly at days 12–15. The early repopulation peak was probably formed by the differentiation and accumulation of IgA blasts, recirculating IgA‐bearing cells and some IgA precursors. The former 2 cell types homed directly back, while the later homed indirectly via spleen to the GLP. The late repopulation peak was possibly formed by the homing and differentiation of Peyer's patch IgA precursors arriving in the GLP with membrane immunoglobulins unchanged. These GLP IgA precursors migrated first to the spleen and later back to the GLP, where they differentiated into IgA p

ISSN:0014-2980    

DOI:10.1002/eji.1830140507

出版商:WILEY‐VCH Verlag GmbH    

年代:1984

数据来源: WILEY

摘要:

AbstractThe monoclonal antibody (mAb) OKT4A (but not OKT4) inhibits thein vitroantibody response of human peripheral blood mononuclear cells. The target of OKT4A mAb is the helper T cell, as the helper cells for the antibody response to trinitrophenylated polyacrylamide beads (TNP‐PAA) are exclusively in the T4 subset. The OKT4A mAb is still suppressive when the anti‐TNP response of cultures of monocyte‐depleted cells is supported by purified interleukin 1. Both the OKT4A mAb and anti‐DR mAb suppress the non‐specific T cell proliferation in the cultures leading to thein vitromAb response. A parallel inhibition is observed for the autologous mixed lymphocyte reaction, the nonspecific B cell response, but the T cell response to mitogens is not affected. These results suggest that the recognition of self major histocompatibility complex class II determinants by the T4 molecule plays a major role in the activation of T helper cells for antibody production to this particulat

ISSN:0014-2980    

DOI:10.1002/eji.1830140508

出版商:WILEY‐VCH Verlag GmbH    

年代:1984

数据来源: WILEY

摘要:

AbstractThe role of I‐A molecules in lectin‐ and antigen‐induced interleukin 2 (IL2) production has been analyzed using monoclonal antibodies. Both lectin‐ and antigen [plus major histocompatibility complex (MHC)]‐induced IL2 production were profoundly inhibited by monoclonal anti‐I‐A antibodies, whereas monoclonal anti‐D and anti‐K antibodies had no effect. The anti‐I‐A‐mediated inhibition of lectin‐induced IL2 production was fully overcome by addition of interleukin 1 (IL1), while no recon‐stitution was observed in antigen (plus MHC)‐specific induction. Anti‐I‐A antibodies were also found to inhibit the T cell‐independent induction of IL1 production.I‐A antigens appear, therefore, to play two distinct roles in the induction of IL2 production: (a) I‐A molecules are directly involved in mediating activation signals to the macrophages at the level of IL1 production; (b) I‐A epitopes act as restricting elements in specific antigen recognition by T helper cells at the level of IL2 production,

ISSN:0014-2980    

DOI:10.1002/eji.1830140509

出版商:WILEY‐VCH Verlag GmbH    

年代:1984

数据来源: WILEY

摘要:

AbstractAttempting to obtain a representative sample of the “natural antibody” repertoire in the developing immune system, we have derived IgM‐secreting hybridomas from 4 normal untreated BALB/c mice of the same litter on day 6 after birth. Partially purified IgM preparations obtained in the supernatants of 70 such clones were each screened in binding assays for reactivity with a panel of 9 IgM antibodies, randomly selected from the same collection. Five of these 9 IgM antibodies were found to react with a considerable number of other IgM in the collection, while the other 4 showed only sporadic reactivity. On the other hand, more than half of the 70 antibodies were found to bind specifically to at least one of these five. With a few exceptions, these reactions showed quantitative levels ranging from 5 to 20% of those observed between either of the two interacting IgM and monoclonal rat anti‐μ antibodies. The selectivity of these reactions indicated V‐region specificity, which was confirmed by analyzing in some detail the reaction between 2 IgM antibodies isolated from the

ISSN:0014-2980    

DOI:10.1002/eji.1830140510

出版商:WILEY‐VCH Verlag GmbH    

年代:1984

数据来源: WILEY

摘要:

AbstractThe lack of response to hen egg white lysozyme (HEL) by C57BL (H‐2b) mice has been demonstrated previously to be related to the induction of suppressor T (Ts) cells which recognize the amino terminal region of HEL. In this report, the nature of the protein determinant required for Tscell induction is more precisely detailed using des‐1,2,3‐HEL (AP‐HEL) prepared with an aminopeptidase purified fromAeromonas proteolytica.Remarkably, the removal of just these three amino acids obliterates the ability of HEL to induce Tscells specific for HEL. Additionally, in contrast to HEL, AP‐HEL is able to prime for anin vitroT cell proliferative response to either AP‐HEL or HEL. Thus, removal of a very limited region of a protein antigen can drastically alter its immunogenic

ISSN:0014-2980    

DOI:10.1002/eji.1830140511

出版商:WILEY‐VCH Verlag GmbH    

年代:1984

数据来源: WILEY