EVIDENCE FOR A POSSIBLE MAJOR HISTOCOMPATIBILITY COMPLEX (BLA) IN CATTLE

Lymphocytotoxic sera have been produced in forty-seven cattle following skin grafting or lymphocyte immunization between dam-offspring pairs. From these sera seventy antilymphocyte reagents have been produced. Seven of the sera were operationally monospecific without absorption, thirty-seven others were made operationally monospecific and twenty-six partially purified by absorption with lymphocytes. Thirty-five of these sera were used in France and an additional thirty-five were used in Scotland. The inheritance of the antigenic factors detected by these sera has been studied in 480 cattle families and the evidence is consistent with the hypothesis that at least seventeen of the factors are inherited in a simple Mendelian fashion. Fourteen of these factors show evidence of linkage with at least one other factor and are likely to be controlled by a limited number of closely linked loci. It is suggested that these loci should be identified as the BLA region.     

大鼠MHC-Ⅰ类基因cDNA的克隆

采用逆转录ＰＣＲ技术自ＳＤ大鼠脾细胞中克隆出全长１１２５个ｂｐ的编码主要组织相容性抗原Ｉ类分子（ＭＨＣ－Ｉ）ｃＤＮＡ，经限制性内切酶图谱分析证实后，定向插入表达载体ｐＢＶ２２０，并筛选出带有插入片断的阳性克隆，为研究在原核或真核表达系统中表达及其在抗原识别，免疫应答中的作用奠定了基础。     

GENETIC STUDIES IN INBRED RATS VII. TENTATIVE MODEL FOR THE MAJOR HISTOCOMPATIBILITY COMPLEX

Several lines of evidence are presented which support a tentative model of the major histocompatibility complex (MHC) of the rat. The serologically defined (SD), lymphocyte defined (LD) and immune response (Ir) loci are separate but linked, and there are probably two loci controlling the serologically defined antigens. The MHC in the rat appears to resemble that in the human more than that in the mouse.     

THE MAJOR HISTOCOMPATIBILITY COMPLEX OF THE GUINEA-PIG

The relationship between the mixed leucocyte reaction (MLR) and the serologically-defined antigens controlled by genes in the guinea-pig B locus (equivalent to the murine D or K region) and I region was investigated in various inbred and partially inbred strains and in guinea-pig families homozygous for their GPLA alleles. No MLR reactions could be detected among guinea-pig families of a closed colony which had been bred to homozygosity for their GPLA antigens. By contrast, animals which differed in their I region showed strong MLR reactivity. Animals with identical I regions as judged by four serologically-defined specificities only, but differ with respect to B locus determinants, yield appreciably lower MLR responses. It appears that in the guinea-pig, as in other mammalian species, the antigenic systems responsible for MLR reactivity are controlled primarily by genes identical with or closely linked to the I region of the major histocompatibility complex.     

COMPARISON OF THE HAPLOTYPES OF THE MAJOR HISTOCOMPATIBILITY COMPLEX IN THE RAT

Two haplotypes which posed difficult problems in serological identification, those of the HW and MNR/N strains, were studied. The HW strain was originally described as a unique haplotype (H-1^h), but breeding difficulties precluded its detailed serological analysis. The red blood cells of the HW strain agglutinate weakly and cross-react with antisera to the Ag-B8 group. Anti-HW antisera cross-react strongly with LEW, ACI and WKA, but absorption with these strains did not produce an adequate typing serum. By judicious selection of recipients, however, an appropriate typing reagent could be made; a particularly useful one was (BUF × MR)F₁ anti-HW absorbed with WKA red blood cells. The HW haplotype segregated appropriately in a (DA × HW)F₂ population. The HW strain is a low responder to poly (Glu⁵²Lys³³Tyr¹⁵). The H-1^h haplotype of this strain was designated Ag-B12. The MNR/N strain had not previously been studied serologically, although its MLR type had been defined as H-1^c (MLR-5). Antisera to MNR/N crossreacted strongly with the H-1^{a, b, d, f} haplotypes, but MNR/N red blood cells agglutinated only weakly with many antisera. An operationally monospecific reagent antiserum to the MNR/N haplotype could not be made. The uniquencess of the MNR/N haplotype was shown by F₁ tests with LEW.1A, LEW.1D and LEW.1F, by various serological analyses, including production of antisera against MNR/N and in the MR strain; by segregation studies with (LEW × LEW.1D)N₅ and (DA × DA.MNR)N₄ segregating back-cross populations, and by grafting skin from (DA × DA.MNR)N₄ homozygous and heterozygous animals to DA recipients. The MNR/N strain is a high-responder to poly (Glu⁵²Lys³³Tyr¹⁵). The MNR/N haplotype of this strain was designated Ag-B13 (H-1^m). The data led to the working hypothesis that the MNR/N strain may be a recombination between the A region of H-1^d and the B region of H-1^c. In addition, the H-1^d private specificity at the A region was probably lost by a deletion mutation which left the main complex of public specificities intact.     

ANALYSIS OF THE MAJOR HISTOCOMPATIBILITY COMPLEX MICROSATELLITE CL1 IN DIFFERENT HUMAN HAPLOTYPES

Characterization of the region between HLA-B and the TNF loci in the human MHC revealed the presence of duplicated loci, named CL1 and CL2, that included repeat sequences. Development and use of a PCR typing methodology that amplified both CL microsatellites simultaneously indicated that PCR product patterns analysed on native agarose gels were allelic (Abraham et al., 1992). The purpose of the current study was to determine the molecular explanation for the unique patterns achieved. Sequence analysis of the CL1 locus from 32 chromosomes representing 10 ancestral haplotypes indicated that six alleles were present. The CL microsatellites also provided an opportunity to study the evolutionary relationships between MHC haplotypes from different racial groups. Sequence comparison of closely related ancestral haplotypes from different racial groups suggested that the CL1 microsatellite has not changed in the period since divergence.     

INVESTIGATION OF THE ASSOCIATION OF MAJOR HISTOCOMPATIBILITY COMPLEX GENES,INCLUDING HLA CLASS I,CLASS II and TAP GENES,WITH CLINICAL FORMS OF CROHN'S DISEASE

The aim of this study was to determine immunogenetic markers of susceptibility in Crohn's disease (CD), taking the different features of the clinical course of the disease into account. HLA class I, HLA class II and TAP transporter gene polymorphisms were studied using DNA typing methods. Gene and antigen frequencies were analysed and compared in a group of 102 CD patients and 200 unrelated healthy controls from the same area. Analysis of the whole CD patient population revealed no definite association with either HLA or TAP gene alleles, with the exception of an association with DRB1*1302 (P_c < 0.05). However, when clinical subgroups of patients were considered, specific associations with some genetic markers were found. The most definitive results involved a genetic association in the group of patients who did not respond to glucocorticoid therapy. This group was characterized by a high frequency of HLA-DRB1*04 (P < 0.05). Conversely, a positive association with the TAP2-A allele was found in cortico-responder patients (P_c < 0.03). Furthermore, analysis of the distribution of HLA class II alleles in relation to the presence of extra-intestinal manifestations revealed an association with the DQB 1*0501 or *0503 suballele of DQ5 (P < 0.05). Finally, patients with lesions in the small bowel were more frequently HLA DRB1 *07 (P < 0.05). The present study supports the concept of clinical heterogeneity in Crohn's disease associated with a background of genetic heterogeneity.     

MAP OF MAJOR HISTOCOMPATIBILITY COMPLEX SUBREGIONS INFLUENCING VAGINAL SEPTA FREQUENCY

The frequency of dorso-ventral vaginal septa (DVS) in mice in influenced by genes associated with the major histocompatibility complex, H-2. Data shows that two subregions within the H-2 complex, K-E_β and D, have a very strong influence on the frequency, while the E_β-S subregion appears to have a weak effect.     

IMMUNOCHEMICAL EVIDENCE FOR MULTIPLE β UNITS OF THE CLASS II MOLECULE IN THE RAT

The RTI-B/D region-associated antigens which were serologically defined in the previous study (Ohhashi et al., 1981), were partially purified from membranes of a rat B cell leukaemia, KNL-14. Sequential immunoprecipitation test, with the partially purified ¹²⁵I-B/Da^k preparation using four different rat alloantisera, including a monoclonal antibody, disclosed three distinctive populations of β units of the class II molecules. Highly purified β units of three discriminable class II molecules were shown to have different structural properties in terms of molecular weights and of electrophoretic profiles on the isoelectric focusing. The β units shifted to a position of higher molecular weight on SDS-PAGE under reducing condition, thus suggesting to carry intradisulfide bonds. Furthermore, the highly purified β units crossreacted with murine anti-Ia sera. The rebinding test revealed that at least two discriminable species of β units cross-react with anti-I-A^k monoclonal antibody, whereas β units purified by binding with the IE4 monoclonal antibody cross-reacted with anti-I-A^b and/or anti-I-A^d antiserum. On the basis of structural and antigenic properties, we have postulated that the rat class II region can be divided into at least three subregions, each containing a locus which encodes a distinctive β unit of the class II molecule.     

LINKAGE RELATIONSHIPS OF THE LOCI OF THE MAJOR HISTOCOMPATIBILITY COMPLEX IN FAMILIES WITH A RECOMBINATION IN THE HLA REGION

A number of families with an established recombination in the major histo-compatibility complex has been investigated for markers known to be coded by genes of this linkage group. The results provide further data on the relative position of the loci for HLA-A, HLA-B, HLA-C, HLA-D, Bf, Chido, Rodgers and PGM₃ on chromosome 6. A positive lodscore for linkage between HLA and blood group P was found; lodscores between HLA and nineteen other markers were negative.     

HUMAN AND MURINE TUMOURS: CHANGES IN CELL SURFACE STRUCTURES CODED BY THE MAJOR HISTOCOMPATIBILITY COMPLEX REGION

Serological and structural changes of surface markers involved in immune reactions may occur in human and murine tumour systems. Thus nine out of twenty-one human tumour cell lines and SV₄₀-transformed fibroblasts differed from autologous lymphoblastoid cells or fibroblasts in their reactivity with HLA allonatisera. H-2 antigens isolated from the murine tumour cells 6C3HED and TP 1422, undergo structural changes. An alien HLA-B7 was detected in sera from two melanoma patients. The serologic activity on H-2 antigens was significantly increased in the serum and ascites fluid of tumour bearing mice. Additionally, human SV₄₀-transformed fibroblatsts acquire receptors for monkey red blood cells and the murine lymphosarcoma cells 6C3HED express receptors for sheep red blood cells.     

INFLUENCE OF THE MAJOR HISTOCOMPATIBILITY COMPLEX IN THE PIG (SLA) ON SERUM HAEMOLYTIC COMPLEMENT LEVELS

Sera from fourty-six non-congenic adult pigs from one inter-related herd were tested for their haemolytic serum complement levels. A comparison of these data with the major histocompatibility complex (SLA) genotypes of these animals resulted in the demonstration of highly significant differences in lytic activity between sera obtained from animals of two distinct SLA haplotypes. These data showed a high correlation between the SLA complex and the level of haemolytic activity.     

LINKAGE OF NEURAMINIDASE AND α-MANNOSIDASE TO THE MAJOR HISTOCOMPATIBILITY COMPLEX IN THE RAT

Variation in enzyme activity of liver neuraminidase and in electrophoretic mobility of liver α-mannosidase is controlled by a gene or by independently acting genes linked to the major histocompatibility complex of the rat.     

RABBIT MAJOR HISTOCOMPATIBILITY COMPLEX.: III. MULTIPLE CLASS II DRβ GENES AND RESTRICTION FRAGMENT LENGTH POLYMORPHISM OF THE CLASS II α AND β GENES

Several class II α and β chain genes of the rabbit MHC have been cloned and classified into three distinct subregions, R-DP, R-DQ and R-DR, based on their homology to the corresponding HLA-DP, -DQ and -DR genes. The organization of the rabbit MHC class II genes has now been studied in greater detail by analysing genomic DNA of an inbred III/J strain and several other RLA-D homozygous rabbits, with DNA probes derived from cloned R-DRβ genes. Eight previously cloned R-DRβ genes were shown to be allelic forms of five R-DRβ loci. Genomic blot analyses of DNA from seven rabbits homozygous for different RLA haplotypes revealed that the germline contains a total of approximately seven class II β genes, one DQβ, one DPβ and five DRβ. Extensive allelic polymorphism was identified by RFLP analysis using DQ and DR probes; limited RFLP was observed with DP probes. RFLP analyses allowed us to distinguish two haplotypes which had not been previously distinguished by MLR. Such RFLP analyses will be useful for identifying MHC ‘compatible’ rabbits for various immunobiological studies, including transplantation.     

ORIENTATION OF LOCI IN THE MAJOR HISTOCOMPATIBILITY COMPLEX OF THE RAT AND ITS COMPARISON TO MAN AND THE MOUSE

Among 290 F2 progeny of an r10 x ACP cross were two recombinants which allowed the loci for glyoxalase-1 and neuraminidase-1 to be mapped relative to the RT1.A and dw-3 loci in the major histocompatibility complex (MHC) of the rat. In 673 progeny of the same cross there was a recombinant between ft and dw-3, and in 403 progeny of the backcross BY1 x (BY1 x BDIX)F1 there was another recombinant between ft and dw-3. These data, combined with those from previous studies, provide the information for constructing a detailed map of the rat major histocompatibility complex: the gene order and size in the rat are very similar to those in the mouse and different from those in man and in the other species that have been studied. Comparison of the structures of the MHC in the various species leads to a hypothesis about the evolution of the MHC which involves sequential duplications of the genes coding for class I and class II loci and an inversion in the prototypic muridae which placed the class II loci between the class I loci.     

MAJOR HISTOCOMPATIBILITY COMPLEX LOCATED COMPLEMENT C4 AND STEROID 21-HYDROXYLASE GENE REARRANGEMENTS IN COUPLES WITH RECURRENT SPONTANEOUS ABORTIONS

Major Histocompatibility Complex (MHC) class III located complement C4 and steroid 21-hydroxylase (21OH) genes, which form various deletion and duplication units, were studied by Taq I Restriction Fragment Length Polymorphism (RFLP) in 58 Finnish couples who suffered recurrent spontaneous abortions (RSA). The gene rearrangements found in the RSA couples did not differ from those in the controls.     

COMPARISON OF THE HAPLOTYPES OF THE MAJOR HISTOCOMPATIBILITY COMPLEX IN THE RAT IV. THE SIX ORIGINAL AG-B HAPLOTYPES

The six original haplotypes described in the Ag-B system were compared with their counterparts in the H-1 system. Antisera to the Ag-B haplotypes raised in inbred rats and antisera to H-1 haplotypes raised in congenic lines were tested against various panels of cell from inbred and congenic lines by the dextran and Ficoll haemagglutination methods. The private and strong public specificities detected in both systems were the same, but there were some minor differences in the intermediate and weak reactivities detected. The cross-reactivity of the antisera raised in inbred rats was broader than that of antisera raised in congenic lines. The identity of the antigenic products detected in the two systems by the dextran and Ficoll tests was further confirmed by a variety of absorption analyses and by F1 tests. This study completes the systematic serological comparison of the haplotypes of the major histocompatibility complex of the rat described originally in the Ag-B and H-1 systems.     

THE ROLE OF REGIONAL DIFFERENCES IN THE MAJOR HISTOCOMPATIBILITY COMPLEX IN THE PRODUCTION DURING PREGNANCY OF A SERUM FACTOR INHIBITING MACROPHAGE MIGRATION

The response by the mother to the paternal antigens of her foetus was evaluated in the rat by the production of a serum factor which inhibits macrophage migration (serum inhibitory factor, SIF). The SIF response depended upon antigenic differences controlled by genes within the major histocompatibility complex (MHC), as demonstrated by the use of congenic strains. Differences between mother and foetus within the RT1.A* region of the MHC led to SIF stimulation, whereas, differences in the RT1.B region did not. The SIF response followed the course of the pregnancy: it began at the time of implantation, reached a maximum at birth and then fell precipitously. In contrast, the SIF response to skin grafting did not correlate with differences in the MHC. Thus, the antigenic factors stimulating this maternal response to foetal antigens appear to depend upon a unique type of genetic difference, and this may be a factor in the apparent immunologic privilege enjoyed by the foetus during gestation.     

COMPARISON OF HAPLOTYPES OF THE MAJOR HISTOCOMPATIBILITY COMPLEX IN THE RAT I. THE Ag-B7 (H-18) AND Ag-B8 (H-1k) HAPLOTYPES

Two haplotypes of the major histocompatibility complex of the rat, Ag-B7 and Ag-B8, have been compared with known H-1 haplotypes using the F₁ skin-graft test and the dextran haemagglutination test. Both of these Ag-B haplotypes were different from the known H-1 haplotypes and determined different private specificities. The Ag-B7 haplotype was denoted as H-1^g and the Ag-B8 haplotype as H-1^k. The complex structure of the serologically detected antigenic products of these haplotypes was determined by means of H-1 congenic lines.