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R M Horton W H Hildebrand J M Martinko L R Pease 《Journal of immunology (Baltimore, Md. : 1950)》1990,145(6):1782-1787
The H-2Kf allele and the spontaneous mutant Kfm1 have been cloned using locus-specific sequences. The mutation consists of a cluster of four nucleotide changes, resulting in amino acid substitutions at positions 95 (Leu----Ile) and 97 (Val----Arg). This finding has structural, genetic, and technical implications. The amino acid substitutions are located on the beta-strands of the antigen recognition site. Their influence on the allogeneic properties of the Kf glycoprotein is consistent with the hypothesis that alloreactivity results from alterations in the spectrum of peptides presented to T cells. These substitutions would not, however, be predicted to be directly accessible for binding to antibodies. Nonetheless, the fm1 mutant binds anti Kf alloantisera and mAb much less strongly than the parent molecule, suggesting some indirect effect of these residues on serologic phenotype. The mutant is also interesting genetically because the sequence of the mutated region is identical to the sequence of the Df gene. This implies that there is a gene conversion-like mutational mechanism operating in the H-2f haplotype. Finally, the strategy used to obtain these K-locus cDNA should prove generally useful for isolating other MHC alleles. 相似文献
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Using the fluorescence-activated cell sorter (FACS II), we have analyzed the expression of H-2K- and H-2D-gene products on the membrane of various cellular components of the murine immune system. Using this serological technique we show a basic difference between T and B lymphocytes. Whereas all cellular components analyzed — hydrocortisone-resistant thymocytes, splenic T and B lymphocytes, macrophages and bone-marrow cells — expressed H-2K-subregion-encoded alloantigens at a high density, it seems that the high density expression of H-2D-encoded alloantigens is restricted mainly to B cells and to macrophages. Hydrocortisone-resistant thymocytes, splenic T lymphocytes and bone-marrow cells, on the other hand, showed significant expression of the H-2D alloantigens only at low membrane density. These results, then, provide evidence for the existence of an imbalance in serologically detectable expression of H-2K- and H-2D-region-gene products on the cell membrane of various cells comprising the murine immune system.Abbreviations usedin this paper DTH
delayed type hypersensitivity
- FCS
fetal calf serum
- FITC
fluorescein isothiocyanate
- HrT
hydrocortisone-resistant thymocytes
- Ig
immunoglobulins
P. De Baetselier is an EMBO and Euratom postdoctoral fellow 相似文献
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Klaus Pfizenmaier Hartmut Jung Roland Kurrle Martin Röllinghoff Hermann Wagner 《Immunogenetics》1980,10(1-4):395-404
Herpes-simplex-virus (HSV) specific, H-2k-restricted, immune cytotoxic T lymphocytes also lyse noninfected H-2d target cells. Genetic mapping studies revealed that HSV-specific Dk-restricted CTL cross-react with allogeneic targets expressing Dd alloantigens. Cold target inhibition experiments indicate that only a minority of HSV-specific CTL mediate cross-reactive cytolysis. The data give an example of where the phenomenon of H-2-restricted versus nonrestricted responsiveness is not due to distinct subsets of T cells but solely depends on the antigenic determinants recognized.This work was supported by the SFB 107 and the Stiftung Volkswagenwerk. 相似文献
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Herpes-simplex-virus (HSV) specific, H-2k-restricted, immune cytotoxic T lymphocytes also lyse noninfected H-2d target cells. Genetic mapping studies revealed that HSV-specific Dk-restricted CTL cross-react with allogeneic targets expressing Dd alloantigens. Cold target inhibition experiments indicate that only a minority of HSV-specific CTL mediate cross-reactive cytolysis. The data give an example of where the phenomenon of H-2-restricted versus nonrestricted responsiveness is not due to distinct subsets of T cells but solely depends on the antigenic determinants recognized. 相似文献
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Serological characterization of three K-S interval recombinant strains, TBR2 (H-2at2), TBR3 (H-2at3) and AIR 1 (H-2a2) was performed using anti-H-2, Ia, Ss and Slp antisera. The data presented here reveal that the crossover events in both TBR2 and TBR3 occurred between the I-A and I-E subregions. In both cases, the H-2K and I-A subregions were derived fron the H-2t1 of chromosome, while the I-E, S and H-2D regions were derived from the H-2b chromosome (KsAkEbSbDb). The H-2a2 chromosome resulted from a crossover event between the H-2a1 and H-2i9 chromosomes. Ia and Ss typing of AIR 1 suggested that the K to I-E regions originated from H-2a1 and the S and D regions originated from H-2i9 (KkAkEkSbDd). 相似文献
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Discrimination between mammalian RNases H-1 and H-2. 总被引:1,自引:0,他引:1
The two principal RNases H in mammalian cells, H-1 and H-2, differ in their responses to sale, divalent metal, and sulfhydryl inhibition. Specific reaction conditions that provide unambiguous discrimination between RNases H-1 and H-2 with only two assays are described. The assays were used for identification in a new purification procedure for RNases H-1 and H-2. 相似文献
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Klaus Pfizenmaier Hubertus Stockinger Martin Röllinghoff Herman Wagner 《Immunogenetics》1980,11(1):169-176
Cytotoxic T lymphocytes generated in the course of an HSV-infection of CBA (H-2 k ) mice not only lyse syngeneic, virus-infected target cells but also cross-react with noninfected target cells expressing the Dd alloantigen. On the effector cell level, this alloreactivity is mediated by virus-specific CTL's that are restricted to H-2Dk determinants. On the prekiller cell level, the anti-HSV-reactive T cells exhibiting cross-reactivity for Dd alloantigen could be positively selected on H-2d spleen-cell monolayers. After differentiation into cytolytic effector cells, target cells expressing Dd alloantigens and syngeneic HSV-infected target were lysed with equal efficiency. The results imply that the phenomenon of H-2-restricted versus nonrestricted T-cell reactivity is not due to distinct T-cell subsets, but rather is dependent on the antigeneic determinants recognized. 相似文献
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Korten S Wilk E Gessner JE Meyer D Schmidt RE 《Journal of immunology (Baltimore, Md. : 1950)》1999,163(11):5896-5905
NK cells reject non-self hematopoietic bone marrow (BM) grafts via Ly49 receptor-mediated MHC class I-specific recognition and calibration of receptor expression levels. In this paper we investigated how Ly49+ subset frequencies were regulated dependent on MHC class I expression. The development of donor and host Ly49A+ (recognizes H-2Dd and H-2Dk ligands) and Ly49C/I+ (Ly49CBALB/c recognizes H-2Kb, H-2Kd, and H-2Dd, and Ly49CB6 recognizes only H-2Kb) NK cell frequencies were monitored for 120 days in murine-mixed allogeneic BM chimeras. C57BL/6 (H-2b) BM was transplanted into BALB/c (H-2d) mice and vice versa. Peripheral NK cell populations were examined every 5 days. Chimerism was found to be stable with 80-90% donor NK cells. In contrast to syngeneic controls reexpressing pretransplant patterns, donor and host NK cells revealed new and mainly reduced subset frequencies 55 days after allogeneic transplantation. Recipient NK cells acquired these later than donor NK cells. In H-2d --> H-2b chimeras Ly49A+, Ly49C/I+, and Ly49A+/Ly49C/I+ proportions were mainly diminished upon interaction with cognate ligands. Also in H-2b --> H-2d chimeras, Ly49A+ and Ly49A+/Ly49C/I+ subsets were reduced, but there was a transient normalization of Ly49C/I+ proportions in the noncognate host. After 120 days all subsets were reduced. Therefore, down-regulation of developing Ly49A+ and Ly49C/I+ chimeric NK cell frequencies by cognate ligands within 7-8 wk after BM transplantation may be important for successful engraftment. 相似文献
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Herpes-Simplex-virus-specific, H-2Dk-restricted T lymphocytes bear receptors for H-2Dd alloantigen 总被引:2,自引:0,他引:2
Cytotoxic T lymphocytes generated in the course of an HSV-infection of CBA (H-2k) mice not only lyse syngeneic, virus-infected target cells but also cross-react with noninfected taraget cells expressing the Dd alloantigen. On the effector cell level, this alloreactivity is mediated by virus-specific CTL's that are restricted to H-2Dk determinants. On the prekiller cell level, the anti-HSV-reactive T cells exhibiting cross-reactivity for Dd alloantigen could be positively selected on H-2d spleen-cell monolayers. After differentiation into cytolytic effector cells, target cells expressing Dd alloantigens and syngeneic HSV-infected target were lysed with equal efficiency. The results imply that the phenomenon of H-2-restricted versus nonrestricted T-cell reactivity is not due to distinct T-cell subsets, but rather is dependent on the antigeneic determinants recognized. 相似文献
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P C Doherty J R Bennink P J Wettstein 《Journal of immunology (Baltimore, Md. : 1950)》1981,126(1):131-133
Lymphocyte populations from B6, C-H-2bml (KbmlDb) mutant mice cannot, after both in vivo and in vitro negative selection for alloreactivity, be induced to recognize vaccinia virus presented in the context of H-2Kb. This finding may mean that the T cell receptor(s) expresses a component that is very specific for a particular "active site" on the self-H-2 molecule. Alternatively, (if recognition is directed at a virus-H-2 complex) the more similar 2 H-2 molecules are, the more likely it may be that precursor thymocytes in the mutant with the capacity to bind H-2Kb + vaccinia virus may be deleted during ontogeny as a result of cross-reaction with H-2Kbml + endogenous antigen. 相似文献
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