HLA-DRW4 antigen linkage in patients with hypertrophic obstructive cardiomyopathy

To determine the association of histocompatibility (HLA) genes in patients with hypertrophic cardiomyopathy, we determined HLA-A, HLA-B, HLA-C, and HLA-DR specificities in 33 Japanese patients (15 with the obstructive type off hypertrophic cardiomyopathy, and 18 with the nonobstructive type). HLA-DRW4 was found in 73% of patients with hypertrophic obstructive cardiomyopathy, as compared to 33% of 144 normal controls (p < 0.005). HLA-DRW4 occurred in 33% of those with hypertrophic nonobstructive cardiomyopathy, and there was no significant difference as compared with controls. Thus, hypertrophic obstructive cardiomyopathy is associated with genes in the HLA-DR region and immunogenetic factors linked to HLA appear to play a role in the pathogenesis. This work is the first attempt at demonstration of HLA-DR antigen in hypertrophic cardiomyopathy.

Multiple sclerosis in the Orkney and Shetland Islands. III: Histocompatibility determinants

Histocompatibility testing was performed in 48 multiple sclerosis patients and two carefully matched control groups in Orkney Islands, an area of high multiple sclerosis prevalence. The frequency of HLA-A3, HLA-B7, and DW2 was comparable in patients and controls. However, HLA-B7 was significantly more common in female patients compared with male patients. A B-cell alloantigen (B-cell 4) was also as frequent in patients as among controls. Strong linkage between HLA-B7, DW2 and B-cell 4 occurred in controls, but not patients; the linkage was particularly striking in female controls. These data are not consistent with theories that relate certain of the histocompatibility antigens to the aetiology of multiple sclerosis.

Multiple sclerosis in the Orkney and Shetland Islands. V: The effect on viral titres of histocompatibility determinants

HLA phenotypes were correlated with serum antibody titres to eight viruses in patients with multiple sclerosis and two matched control groups in the Orkney Islands. In patients, no specific HLA antigen was associated wtih increased or decreased viral titres. However, HLA-B7 was significantly correlated with higher measles titres in healthy controls. Furthermore, controls who had the HLA haplotypes, B7, DW2 ad B-cell 4, demonstrated significantly higher antibody titres to measles and rubella than controls without these determinants (P less than 0.005). To determine the effect of age, sex, and other variables upon viral titres, regression analysis was undertaken. A significant proportion of measles titre variance in patients was explained by sex and clinical factors. Among normal controls, HLA determinants explained a significant amount of measles and rubella titre variance. These data suggest that viral titres in normal individuals are influenced by certain HLA antigens and give indirect evidence that another, as yet undefined, determinant in the histocompatibility complex governs the immune response.

Genetic susceptibility to multiple sclerosis: a linkage analysis with age-of-onset corrections

To test the hypothesis that a multiple sclerosis susceptibility (MSS) gene is linked to the HLA loci, formal linkage analysis was conducted on 40 multiplex families, 20 each from the Seattle and Los Angeles areas. The computer program LIPED was utilized. A dominant model of inheritance was assumed. Penetrance values of 0.05, 0.35, and 0.67 were entered into the analyses, and an age-of-onset correction was incorporated. The resulting lod scores were supportive of linkage at the lower penetrance levels. The maximum lod score, 2.411, at an estimated recombination fraction of 0.10 in both males and females, was generated at a penetrance value of 0.05. With a penetrance value of 0.67, the lod scores did not support linkage. Under an autosomal dominant model of inheritance, the results were supportive of linkage when the presumed penetrance of the MSS gene is low. The results also confirmed the importance of incorporating an age-of-onset correction into linkage analyses.

B cell antibodies and crossmatching

Over 200 cadaver donor transplants were crossmatched against T and B lymphocytes at 5 and 37 C. Of 54 positive B cell crossmatches, one-half had cold antibodies and one-half had warm antibodies. The 1-year transplant survival was 58% for B-cold-positive crossmatches and 42% for B-warm-positive crossmatches. The B-warm-positive crossmatches, when subdivided into those with strong HLA-DR antibodies showed a 27% 1-year transplant survival rate. We conclude that B cell-positive crossmatches with HLA-DR antibodies are deleterious and that those with cold anti-IgM antibodies may enhance graft survival.

HLA types and immunity in multiple sclerosis

HLA types and levels of humoral and cell-mediated immune responses to several antigens were studied in a large group of patients with multiple sclerosis, and in controls. Patients were more likely than controls to have the DRw2 antigen. They had higher mean antibody titers to measles but not to cytomegalovirus, herpes 1, or herpes 2, and had less competent cell-mediated responses. Antibody titers to measles were lower and cell-mediated immune responses were more effective in patients with the DRw2 antigen in patients than in patients without it. This apparent specificity for measles suggests that the etiology of multiple sclerosis is related to the immune response to measles or related viruses.

ABH and Lewis antigens on lymphocytes: screening of pregnant women's sera with the B-cell cytotoxicity test

Five phenotypes related to the ABH-Lewis substances were defined by the B-cell lymphocytotoxic test. These five antigens are built up in a stepwise fashion by the action of the glycosyl transferases specified by the Le, H, and the A, B genes onto the same ABO percursor molecules. The comparison of their chemical structures with the cluster analysis obtained by cytotoxicity suggests that antibodies reacting with large antigenic structures (pentasaccharides) have a more restricted specificity than antibodies reacting only with smaller antigenic determinants (trisaccharides).

Genetic susceptibility to multiple sclerosis

Previous studies of histocompatibility (HLA) types in multiple sclerosis (MS) families did not provide convincing proof of an HLA-linked susceptibility factor. In 12 families we studied, all MS cases in each family shared at least one chromosome. The probability of this occurring in the absence of genetic linkage is approximately 0.001. The estimated penetrance is 5 percent, implying that the genetic susceptibility factor may be a necessary but not a sufficient cause of MS. Additional studies are needed to identify other differences between affected and unaffected susceptible individuals.

HLA-DRW4 in 91% of Jewish pemphigus vulgaris patients

HLA-DRW4 was found in all 11 female and 10 out of 12 male Jewish patients with pemphigus vulgaris, a frequency of 91% in all, which was significantly higher than the 25% frequency among normal Jewish controls. The relative risk was 31.5. The BW38-DRW4 haplotype occurred in 12 out of 22 patients (55%) but in only 2% of White non-Jews and 11% of normal Jewish people.

Dilutions and specificity analysis of pretransplant sera

Six serial dilutions of 51 sera from pretransplant patients were reacted against T and B lymphocytes at 5 degrees C and 37 degrees C. By the use of defined panels of T and B lymphocytes it could be shown that 10% of the 51 positive sera contained T-warm antibodies against HLA-A, -B, and -C specificities. There were 28% of the sera that had antibodies against non-HLA antigens reactive to B lymphocytes in the cold. Other sera contained mixtures of HLA and non-HLA antibodies. By dilution analysis of the sera, the mixtures could be detected and the HLA specificities identified. This ability to distinguish between HLA and non-HLA antibodies should be important in classifying pretransplant patients into high- and low-risk patients. Prior evidence that we have presented suggests that the non-HLA antibodies may be enhancing antibodies.

Enhancement of human kidney allografts by cold B-lymphocyte cytotoxins

The sera of 233 kidney transplant patients before transplantation were tested by cytotoxicity against a panel of B and T lymphocytes at 5 degrees C and 37 degrees C. The results divided the patients into four groups: those whose sera reacted with B lymphocytes at 5 degrees C; those reacting with B lymphocytes at 5 degrees C and 37 degrees C; those reacting with T lymphocytes at 37 degrees C; and those with no antibodies. The patients with pre-transplant antibodies reactive with B lymphocytes at 5 degrees C had a significantly higher kidney-transplant survival rate at 6 months (70%) and 1 year (65%) than patients who had no antibodies (47% and 46%, respectively). Patients with antibodies reactive at 37 degrees C had a 6-month survival-rate of 38% when reactive against B cells and 43% when reactive against T lymphocytes. The cold cytotoxins were IgM.

Autoantibody against B lymphocytes

The sera of 20 out of 99 (20%) normal males and females were shown to have antibodies that kill their own B lymphocytes. The sera were specifically cytotoxic to B lymphocytes and not T lymphocytes. Allogeneic B lymphocytes were also killed by these autocytotoxins. Maximum killing of B lymphocytes occurred when the incubation temperature in serum was 5 degrees C and complement incubation temperature was 20 degrees C. Under these cold conditions, some sera reacted up to a dilution of 1/16. These results suggest that positive B-lymphocyte crossmatches found in kidney transplantation do not detect alloantibodies. Since the B-cell autoantibodies tend to appear at the time of immunisation, their role as autoregulators of the antibody response is an intriguing possibility.

Relation between HLA-DW and the b-lymphocyte specificities

Homozygous DW typing cells were tested for six B-lymphocyte specificities. All four of the second locus specificities of B lymphocytes were strongly associated with the DW specificities. DW1 typing cells were B group 6, DW2 were B4, DW3 were B5, and LD107 were B3. The first B-cell locus antigens 1 and 2 tended to be uniform within the DW groups. From an analysis of the typing responses of a panel of cells to the homozygous typing cells, it has become apparent that the first B-locus specificity present on the homozygous typing cells also plays a role in determining whether a typing response is obtained or not. Thus, the DW3 typing cells were themselves B2 and B5, and cells having B2-B5 were most frequently nonreactive to DW3 in mixed lymphocyte culture. Homozygous typing cells therefore mainly detect the second B-cell locus antigens and, to a lesser degree, the first locus specificities. Stated another way, homozygous typing cells do not define a single specificity, but rather the presence of two B-lymphocyte specificities, even though their responses often reflect matching of only the second B-locus specificity.

B-lymphocyte haplotypes in asthma families

Thirty families in whom at least one member had asthma were typed for five new B-lymphocyte specificities, as well as the antigens of the A and B loci of HLA. The B-cell reactions were consistent with the concept that they were determined by genes linked to the HLA-A and HLA-B loci. Between 22 HLA-identical siblings and 16 two-haplotype different siblings, a significant difference in concordance of reactions for the B-cell groups was noted. The data obtained were most compatible with B-groups 1 and 2 being determined by one locus and B-groups 3, 4, and 5 by another locus. The superhaplotypes of HLA-A, HL-B, and B-cell loci 1 and 2 were then determined. The most striking linkages noted were for the second B-cell locus and the HLA-B locus: B-cell group 3 with HLA-B12, B-cell group 4 with HLA-B7, and B-cell group 5 with HLA-B8, B17, and Bw35.

The role of B-lymphocyte antigens in MLC stimulation

A total of 950 MLC combinations were set up out of which 259 were classified as low MLC response. An attempt was made to predict which of the combinations would give low response by matching the B-lymphocyte specificities and the HLA-A and -B antigens. A statistically significant prediction of a low response was noted for the B-lymphocyte specificities as well as for HLA-A and -B antigens. The fraction of the low response, which was correctly found, was, however, greater with the B-cell specificities than the HLA-A and -B locus antigens. It is concluded that the B-lymphocyte specificities may be either identical or closely linked to the DW specificities. To what extent they are associated with the strong transplantation antigens of man remains to be determined.