HLA-A, B, C and DR antigens in immunoglobulin A deficiency

HLA-A, B, C and DR typing was performed in 21 unrelated healthy blood donors with selective IgA deficiency (< 0.02 G/l of IgA). A significant increase in HLA A1 ( P < 0.05), HLA B8 ( P < 0.01) and HLA DR3 ( P < 0.001) was found. The frequency of HLA A28 was also increased ( P < 0.05). Furthermore, HLA A28 was present in all four donors lacking DR3.     

HLA—DR Typing of Frozen B Lymphocytes

In the complement dependent lymphocytotoxic microtechnique it was found that antibody-killed frozen B lymphocytes are sufficiently stained for reliable reading after 30 min of incubation with trypan blue, while the background of staining is only about 10%. During the next 30 min of incubation, however, the background of staining increases to about 30%, whereafter it remains constant for at least 24 h. Formaldehyde is able to stop the trypan blue uptake by killed or damaged lymphocytes completely. Consequently, if formaldehyde is added to the reactions 30 min after the trypan blue addition, the otherwise rapidly increasing background of staining is kept at an acceptable level of 10%, thus making HLA-DR typing of frozen stored B lymphocytes possible. The trypan blue staining seems rather independent of incubation conditions before the addition of the dye. Similar results were obtained with T lymphocytes.     

HLA-A,B,C and DR antigens in psoriasis

51 psoriasis vulgaris patients and 93 controls were tested for HLA-A,B,C and DR antigenic frequencies. Significant increases of B17, Cw6 and DR7 were documented in the patient group, as well as a decreased frequency of DR1. The significance of these findings is discussed. DR7 occurred more often together with Cw6 in psoriasis patients than in controls, which might suggest that there are at least two interacting HLA linked genes which increase the disease susceptibility and possibly one DR1 linked gene associated with resistence to the disease.     

HLA-A, B, DR antigens and insulin-dependent diabetes in Algerians

HLA-A, B and DR antigens have been investigated in insulin-dependent diabetics and compared to controls in a population of Algerians. A decrease of A1 and DR2 and an increase of Aw 19.2; B8, B18 and especially DR3 were found in diabetics in comparison to controls. The strongest association was found for DR3, which is a good genetic marker of IDD (RR = 8.50) in this population. The frequency of some HLA antigen associations in IDD suggests that the diabetic gene(s) is linked to 2 main haplotypes: Aw 19.2; B18; DR3 and Aw 19.2; B8; DR3. Antigen DR4 was equally represented in IDD (21%) and controls (28.4%), but heterozygote DR3-DR4 was more frequent in diabetics. The relation between IDD and HLA antigens found in the Algerian population is very similar to that described in diabetic Caucasian populations of southern Europe, except for the lack of association with DR4.     

Identification of human minor histocompatibility antigens

Minor Histocompatibility antigen (mHag) disparities between HLA-matched bone marrow donors and recipients are a risk factor for Graft-versus-Host-Disease. Using T cell clones recognizing human mHag in the context of HLA, we have recently identified the HLA-A2.1 restricted HA-2 and the HLA-B7 restricted H-Y. The HLA-B7 restricted H-Y is encoded by the SMCY gene located on the human Y chromosome. It is unknown whether other H-Y mHag are also encoded by the same gene. Therefore we have isolated HLA-A2.1 and HLA-A1 restricted H-Y positive peptide fractions eluted from the respective HLA molecules that are purified by affinity chromatography. These fractions are currently being analysed by tandem mass spectrometry. At present, we are isolating and purifying the mHag HA-1. This non-sex linked antigen is significantly associated with Graft-versus-Host-Disease and may therefore be a suitable candidate for immunotherapy.     

HLA-A, B and DR antigens in patients with gonadal dysgenesis

HLA (human leukocyte antigens) antigens A, B, and DR were determined in a series of 50 patients with gonadal dysgenesis (GD), separated into different groups according to karyotype. There were no significant differences in frequency of HLA antigen types between GD patients and the population control. When frequencies of the HLA antigens in the various GD patient groups by karyotype were compared, only one significant difference was found: HLA-A3 was more common among GD patients with isochromosome X than among GD patients with karyotype 45, X (p<0.001, corr. p<0.008). Although GD patients have a higher expectancy for development of autoimmune disorders, and in our 50 patients thyroglobulin and/or microsomal antibodies were detected in 20 (i.e., 40%), we failed to find any increased frequency of specific HLA antigen types known to be associated with juvenile autoimmune thyroiditis.     

HLA antigens A, B, C and DR in hay-fever families of similar environmental conditions

Investigation of 98 members (healthy and affected) belonging to 17 hay-fever families, for clinical picture, total and specific IgE and HLA A, B, C and DR is presented. There was no significant correlation between hay-fever, total or specific IgE and a certain HLA antigen or haplotype. There was, however, an association between hay-fever and same haplotype within 4 of the 17 families.     

Cryopreservation of human fetal organs

Summary The effects of low temperature preservation on morphology, viability and differentiation capacity of different human fetal organs were studied using transmission (TEM) and scanning (SEM) electron microscopy, in vitro cultivation as well as xenogeneic transplantation. For this purpose fragments of lung, kidney, small intestine, thyroid, brain, liver and spleen from 10 human fetuses (aged 9 to 14 weeks of gestation) were frozen by a three step cooling procedure. After 3 to 12 months the specimens were thawed rapidly and processed for TEM and/or in vitro cultivation and/or transplantation into nude mice. TEM studies on frozen lung, kidney and intestine revealed generally a well preserved ultrastructure whereas liver and spleen fragments appeared highly necrotic. From three fetuses, frozen intestine and lung specimens were used for the establishment of monolayer cultures. Following trypsinization, both epithelial and mesenchymal cells formed a continous layer on the bottom of plastic bottles. During further subpassages the number of epithelial cells decreased resulting in the formation of pure fibroblast cultures. Frozen brain tissue from one fetus was also successfully cultivated forming cell clusters and fiber bundles of variable size at the surface of glass cover slips. Following subcutaneous implantation into nude mice, the vast majority of fragments from lung, kidney, intestine and thyroid was found to growth in the recipients. The growth of xenografts was accompanied by persistence (kidney, intestine) or even increase (lung, thyroid) in cellular differentiation studied by TEM or autoradiography. Transplanted liver and spleen fragments, however, regularly regressed forming solid scars in the subcutaneous tissue of nude mice.In summary, the three-step cooling procedure is an effective method for storage of different human fetal organs preserving morphology, viability and differentiation capacity of the tissues. Thawed specimens may be used for several experiments including in vivo and in vitro studies.In memoriam Prof. Dr. med. G. Töndury, 15.3.1985     

HLA-A,B,C and DR antigens in a sample of the Tunisian population

The HLA-A, B and DR phenotypes of 109 unrelated Tunisian individuals have been determined. The HLA-A and B antigen frequencies were compared with data reported for European Caucasoids and various Arab populations. Most similarities in antigen frequencies were seen between Tunisians and Kabyles from North Africa. A high frequency of HLA-A23 and HLA-Bw50 was observed in Tunisians and all Arab populations. A very close similarity in HLA-DR antigen frequencies exists between Tunisians and European Caucasoids. Linkage disequilibria between alleles of HLA loci were examined; many instances of previously reported antigen associations were seen in Tunisians, together with a number of associations which have not been described elsewhere. Aw34B8 and A2DRw14 are suggested as being common haplotypes in Tunisians.     

Multiplex genotyping of human minor histocompatibility antigens

Minor histocompatibility antigens (mHAg) induce major histocompatibility complex-restricted, T cell-mediated immune responses that may contribute to increased risk of graft-versus-host disease and graft-versus-leukemia effects. Unlike human leukocyte antigen genes, mHAg are encoded by genetically and functionally unrelated genes located throughout the chromosome. The role of mHAg in stem cell transplantation and the population frequencies of mHAg alleles remain unknown due in part to the lack of suitable high throughput methods for genotyping these diverse genes. Here we describe the development and utility of a multiplexed Luminex assay for genotyping human mHAg, including HA-1, HA-2, HA-3, HA-8, HB-1, CD31(125), and CD31(563). The assay uses a multiplexed, allele-independent, gated amplification of mHAg genes followed by differential detection of allele-specific primer extension products using the MultiCode PLx system (EraGen Biosciences, Madison, WI). The alleles are interrogated using a multiplex allele-specific primer extension reaction using primers tagged with EraCodes. The products are hybridized to Luminex beads and the hybridization duplexes are detected using streptavidin-phycoerythrin. The assay resolved the mHAg genotypes of 259 Caucasian donors and provided population estimates of mHAg gene and phenotypic frequencies. All mHAg alleles evaluated in this study exhibited Hardy-Weinberg equilibrium, although some mHAg phenotypes were present in large majority of individuals tested (HA-2, HB-1). This assay will provide a valuable tool for determining mHAg frequencies in other ethnic populations, as well as for establishing the clinical importance of mHAg disparities in stem cell transplantation.     

HLA-A,B and DR antigens in North Carolina Blacks with sarcoidosis

Forty-one Black sarcoidosis patients from North Carolina were typed for HLA-A. B and DR antigens. There were no significant alterations in their HLA antigen frequencies when compared to a control population.     

The distribution of HLA-A,B, DR antigens in Chinese Myasthenia Gravis

The association of HLA antigens with Myasthenia Gravis (MG) in many different races is well known. In this study, HLA-A, B and DR antigens were typed on 65 Chinese MG and 232 controls for HLA-A, B and 61 for DR antigens. A2 and DRw9 increased significantly in patients with MG (p less than 0.025 and p less than 0.05 respectively). DR2 and DR4 had the opposite influence (both p less than 0.005). Several alleles were shown to have relatively high values of P D/A and relative risk but low P A/D and E.F, which suggests the marker heterogeneity of MG. Comparisons of clinically different types of MG, variations of the age of onset and thymic pathology did not show any statistically significant difference in HLA distributions. The clinical implications were discussed.     

Improved B Cell Typing for HLA—DR Using Nylon Wool Column Enriched B Lymphocyte Preparations

A rapid, simple procedure for preparing B lymphocytes using nylon wool has been devised. When mixtures of T lymphocytes, B lymphocytes, and monocytes are applied to nylon wool columns, B lymphocytes can then be removed, virtually free of monocytes. Such preparations (Ad) are 85 +/- 6% SIg+ and have only 3 +/- 1% monocyte contamination. The yield from peripheral blood averages 5% of all mononuclear cells. In contrast, the E rosette depletion method (E-) yields cells which are only 64 +/- 5% SIg+ and have 25 +/- 7% monocyte contamination. The superiority of the nylon method for HLA-DR typing was demonstrated in a comparative study of Ad and E- with eight normal individuals. Cytotoxic scores were higher and a large number of reactions, representing DRw groups and additional cross-reactions, was detected.     

HLA-A,B,C and DR antigens in Asaro speakers of Papua New Guinea

The HLA profile of the Asaro speakers of Papua New Guinea exhibits restricted polymorphisms. Antigens like AW24, MT1, and MB1 were present in almost every individual assayed. A CW6-related antigen and a DR locus antigen FT19 (a split of DRW6), not previously found in Pacific populations, were observed in a significant number of individuals. Ancestral HLA-B,C haplotypic combinations, such as B13, CW4 and BW60, CW3, were frequently found. Preliminary evidence is provided for an association between BW62 and CW6 in this population. The observed distributions of multiple-locus heterozygosities are similar to those expected under the null hypothesis of linkage equilibrium. The results indicate that the Asaro, among other highland populations, have been isolated long enough for pre-existing linkage disequilibria at recombinational distances of 0.8% or more (such as occur with HLA-A,B and HLA-B,DR haplotypes) to have broken down.     

Correlations between HLA-D/DR associated Primed Lymphocyte Typing (PLT) defined DP-antigens, HLA-D and HLA-DR antigens

A panel of 79 individuals were typed for HLA-D/DR associated Primed Lymphocyte Typing (PLT) defined "DP"-antigens, HLA-D and HLA-DR antigens. Typing for DP-antigens was carried out with local PLT-cells. HLA-D and-DR typing was performed with all homozygous typing cells and all DR-antisera included in the 8th International Histocompatibility Workshop. Assignments of DP-, HLA-D-and HLA-DR-antigens were done independently and the correlations between DP/D/DR1–8 were analyzed. The panel included random unrelated individuals, and individuals previously found to have one or no identifiable HLA-D antigen (B). In the random group, 80% of the individuals were assigned to possess the same antigen with the 3 techniques, while this was only the case in 46% of B-group individuals. The overall correlation coefficients, r, for the antigens HLA-Dw/-DR/DP1–8 were 0.95 (DP/D), 0.94 (DP/DR), and 0.89 (D/DR). There is a remarkably strong correlation between HLA-D and-DR typing results concerning D/DR1–8, in particular in random individuals. It is possible to select PLT-cells that give typing results which are almost identical to those of HLA-D and-DR typing. When discrepant results were seen, HLA-DR was in general "broader" than DP which in turn was broader than HLA-D, indicating that it may be possible to split HLA-DR/DP1–8 into more "narrow" specificities.