Excess of HLA parental sharing in families with Turner patients

In utero selection processes are probably related to mother-father compatibility as has been reported in abortion-prone couples and in Down syndrome studies. In order to analyse this phenomenon, we investigated families with chromosomal imbalance (Turner syndrome). We chose this model because previous data indicated a high frequency of HLA-A31 and B38 in Turner patients and in their mothers. We report high HLA antigen sharing in Turner families and great histocompatibility between mother and affected daughter, not related to abortion histories. The proportion of HLA-A homozygous cases among Turner children was higher than expected. The level of lymphocytotoxic antibodies against fetus in mothers of Turner patients was comparable to that of mothers of families with normal fertility and probably favoured these pregnancies.     

Determination of the frequency of HLA antibody secreting B-lymphocytes in alloantigen sensitized individuals

Sera from prospective transplant patients are usually screened for HLA antibodies prior to transplantation, but presently available tests do not permit quantification of the humoral alloantigen directed response. We adapted a culture system for isolated human B-lymphocytes to assay the secretion of HLA-antibodies on a single cell basis. B-cell supernatants were screened for HLA antibodies by complement dependent cytotoxicity. The assay assigns precursor frequencies for HLA-alloantibody secreting B-lymphocytes (BCPFs), and simultaneously allows for dissection of the humoral alloantigen directed response into its monoclonal components. The lymphocytes of 15 HLA-seropositive multiparous women that were used to validate the assay, were found to contain HLA-BCPFs ranging from 0 to 123 per 10(6) B-lymphocytes (mean: 43 +/- 45 per 10(6) B-lymphocytes). The HLA-specificities of antibodies in the B-cell supernatants were in agreement with serum specificities. Genuine HLA reactivity of B-cell supernatants was confirmed using an ELISA with purified HLA class I antigens. When applied to lymphocytes of patients on transplant waiting lists, the present assay may enable the unraveling of serum specificities in their components, thus supplementing HLA antibody serum screening data.     

HLA genotypes in two three-generation families with rheumatoid arthritis

Two three-generation families from Northern Sweden with rheumatoid arthritis (RA) were clinically examined. Tissue typing was performed for HLA-A, -B, -C, and -DR antigens. No disease-associated haplotype could be defined within these families. Six of nine members with RA were HLA-DR4 positive. Both families had a HLA-DR4 containing haplotype in the first generation and second-generation members married DR4 positive individuals, which probably increased the risk to develop RA in the third-generation members.     

To B or not to B: role of B cells in pathogenesis of arthritis in HLA transgenic mice

Population studies have shown that amongst all the genetic factors linked with autoimmune disease development, MHC class II genes are the most significant. Experimental autoimmune arthritis resembling human rheumatoid arthritis (RA) can be induced in susceptible strains of mice following immunization with type II collagen (CIA). We generated transgenic mice lacking endogenous class II molecules and expressing various HLA genes including RA-associated, HLA-DRB1*0401 and HLA-DQ8, and RA-resistant, DRB1*0402, genes. The HLA molecules in these mice are expressed on the cell surface and can positively select CD4+ T cells expressing various Vβ T cell receptors. Endogenous class II invariant chain is required for proper functioning of the class II transgene. Arthritis development in transgenic mice is CD4+ and B cells dependent. Studies in humanized mice showed that B cells are required as antigen presenting cells in addition to antibody producing cells for the development of CIA. The transgenic mice expressing *0401 and *0401/DQ8 genes developed sex-biased arthritis with predominantly females being affected, similar to that of human RA. Further, the transgenic mice produced autoantibodies like rheumatoid factor and anti-cyclic antibodies. Antigen presentation by B cells leads to a sex-specific immune response in DRB1*0401 mice suggesting a role of B cells and HLA-DR in rendering susceptibility to develop arthritis in females.     

Difference in the ability of HLA serum to react with T and B lymphocyte populations

The ability of HLA sera to react with T and B lymphocytes of human blood was studied. The lymphocytes were separated by removal of one of the cell populations. The method of rosette formation was used, followed by centrifugation in a density gradient and adsorption of B lymphocytes on synthetic fiber. After removal of the B cells the cytotoxic activity of the HLA sera was reduced. Removal of T lymphocytes did not affect the result of the lymphocytotoxic test. It is postulated that B lymphocytes contain more determinants of HLA antigens than T lymphocytes.Laboratory of Immunohematology, Central Institute of Hematology and Blood Transfusion, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR P. N. Kosyakov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 81, No. 6, pp. 698–699, June, 1976.     

HLA antigens in Tlingit Indians with rheumatoid arthritis

HLA-DR4 has been described in association with rheumatoid arthritis (RA) in multiple populations. We have studied HLA antigens in Alaskan Tlingit Indians. HLA-DR4 was decreased in the RA group (n = 32) compared with controls (n = 62) (6% vs 21% p = 0.07). The predominant DR4 allele observed was DRB1*0403 (Dw13.1). The most striking observation in these studies was a marked predominance of the DRB1*1402 allele encoding Dw16 (DRw14). This allele was present in 91% of RA cases, but was also highly prevalent in controls (80%, OR = 2.4 p = 0.20). DRB1*1402 only was observed in 47% of cases and 31% of controls. The DRB3*0101 (DRw52), and the DQA*0501 and DQB*0301 alleles encoding a subset of DQw3 were associated with DRB1*1402 in cases and in controls. HLA-Bw62 was increased in RA cases (28%) compared with controls (8%) (OR = 4.5, p = 0.01, corrected p = ns).     

HLA and rheumatoid arthritis. A study of five families

Five families with two or more members ill with rheumatoid arthritis were investigated clinically. Tissue typing for HLA A, B, C and D/DR antigens was performed. We could not define may HLA haplotype associated with disease within these families. However, the prevalence of the haplotypes containing HLA-DR4 was high, suggesting a direct relationship between DR4 and increased risk of contracting rheumatoid arthritis.     

Associations of HLA microsatellites with rheumatoid arthritis in Singaporean Chinese

Rheumatoid arthritis in Singaporean Chinese has previously been shown to be associated with the DRB1*0405, DRB1*1001 haplotypes and to the DRB1*0901 haplotype when the former two were removed. The present paper focused on eight HLA associated microsatellite markers (TNFa, TNFd, D6S273, TAP1CA, DQCAR, DQCARII, D6S2222, D6S2223) and their allelic associations with Chinese RA. 60 RA patients and 75 healthy controls were studied. It appeared that DQCARII*194/DRB1*0405/TNFa*117 was part of the extended haplotype predisposed to RA, whereas DRB1*0901/D6S273*128 contributed to susceptibility to RA to a lesser degree in Singaporean Chinese. Additionally, a negative association with DQCAR*186/DRB1*0301/D6S273*122/TNFd*124 was observed. No association with disease development was observed in this study.     

Co-segregation of HLA and rheumatoid arthritis in multicase families

Inheritance of parental HLA haplotypes was examined in the offspring of 95 multicase rheumatoid arthritis (RA) families. Overall, in these families there was no evidence of preferential transmission of one parental haplotype, although this might have been expected given the loading of these families with RA cases. However, there was a difference in inheritance when the affected and non-affected offspring were compared. A co-segregation analysis showed that the inheritance of parental HLA haplotypes was different between the affected and the unaffected offspring. Unlike a previous report, no difference was demonstrated in this study between the offspring of affected and non-affected parents. Similarly, the affected offspring of HLA DR4 heterozygote parents were more likely to inherit HLA DR4 than the non-affected offspring. It is concluded first that linkage studies of RA using the affected sib-pair method are not invalidated, which would have been the case in the presence of preferential transmission of HLA to all offspring. Secondly, HLA and specifically HLA-DR4 does co-segregate with RA, and, finally, parental RA status, independent of DR4, has little influence in explaining the genetic susceptibility to RA.     

HLA class II association with rheumatoid arthritis: facts and interpretations

We have reviewed the literature on the association of HLA class II with rheumatoid arthritis (RA). Strong linkage disequilibrium among DQB1, DQA1 and DRB1 alleles makes it difficult to evaluate the individual contribution of each locus. Nonetheless, there is a strong case for the role of DQB1*03 and *04 combined with DQA1*03 in susceptibility to severe RA while DQB1*0501 combined with DQA1*0101 and *0104 weakly predisposes to a mild form of RA. However, it is also clear that DRB1*0401 has a particular role in predisposition to the most severe form of the disease while other DRB1 alleles might provide protection. We would like to propose that in RA, as in type I diabetes, both DQ and DR loci contribute to predisposition to the disease.     

Evaluation of IgA deficiency in Sardinians indicates a susceptibility gene is encoded within the HLA class III region

IgA deficiency (IgA-D) has been associated with the HLA region, in particular with the North European haplotype HLA-A1, -B8, -DR3, but the exact location of the susceptibility gene(s) is unknown. Some reports suggest that a susceptibility gene is encoded in the class II region, while others implicate the class III region. We exploited differences between the common Sardinian and North European HLA-DR3 haplotypes to help localize the IgA-D susceptibility gene(s). With the knowledge that approximately 13% of HLA-DR3 homozygous individuals of North European origin are IgA-D, we examined 43 HLA-DR3 homozygous Sardinians to find that all had normal serum IgA, IgG and IgM levels. A detailed analysis of their MHC haplotypes indicated a common Sardinian HLA-DR3 haplotype TAP1A, TAP2A, HLA-DQB1*0201, -DQA1*0501, -DRB1*0301, LH1-(Z + 2), D3A-(Z + 2), C4B-0, C4A-L, G11-15, Bf-0.4, C2-a, HSP70-7.5, 9N3-(Z + 10), 82I-(Z ? 2), TNFα-9, 62-(Z ? 20), HLA-B18, -Cw5, -A30 which diverges from the common North European HLA-DR3 haplotype telomeric to the HLA-DR region. In parallel studies of five Sardinians with IgA-D, two of the 10 HLA haplotypes (20%) contained HLA-DR3, a frequency similar to that observed in the background population. One of these was the HLA-DR3- B8 North European haplotype, which occurs rarely in Sardinia. Our data favour the hypothesis that a class III region allele, present on the common North European but not on the Sardinian HLA-DR3 haplotype, confers susceptibility to IgA-D.     

Using penalised logistic regression to fine map HLA variants for rheumatoid arthritis

Rheumatoid arthritis (RA) is strongly associated with the human leukocyte antigen (HLA) genomic region, most notably with a group of HLA-DRB1 alleles termed the shared epitope (SE). There is also substantial evidence of other risk loci in the HLA region, but refinement has been hampered by extensive linkage disequilibrium (LD). Using genotype imputation, we analysed 6575 RA cases and controls with genotypes at 6180 HLA SNPs; about half the subjects had four-digit DRB1 genotypes. Single-SNP tests revealed hundreds of strong associations across the HLA region, even after adjusting for DRB1. We implemented penalised logistic regression in a multi-SNP association analysis using the double-exponential (DE) penalty term on the regression coefficients and the normal-exponential-gamma (NEG). The penalised approaches identified sparse sets of SNPs that could collectively explain most of the association with RA over the whole HLA region. The HLA-DPB1 SNP rs3117225, was consistently identified in our analyses and was confirmed by results from the North American Rheumatoid Arthritis Consortium study (NARAC). We conclude that SNP selection using penalised regression shows a substantial benefit over single-SNP analyses in identifying risk loci in regions of high LD, and the flexibility of the NEG conveys additional advantages.     

Variable HLA expression on deceased donor lymphocytes: Not all crossmatches are created equal

Flow cytometric crossmatch tests are used to detect donor-specific antibody and determine eligibility for transplantation. Crossmatch sensitivity is dependent on lymphocyte quality, to include HLA expression on the cell surface. The impact of HLA expression variability on crossmatch reactivity was examined using lymphocytes isolated from different donor types: deceased donor (DD) versus living donor (LD) and tissue sources (blood, spleen, or lymph nodes). HLA class I expression was similar on B cells isolated from LD blood, DD spleen, and DD lymph nodes, but significantly lower on B cells isolated from DD blood (p = 0.0004). In contrast, class II expression on B cells and class I on T cells were significantly higher in LD blood than all DD tissues. Within DD tissues, spleen provided the highest expression of class II on B cells and class I on T cells. HLA expression on B cells, but not T cells, was impacted by memory (CD27+) versus non-memory status. Importantly, HLA expression differences on lymphocytes isolated from the same donor but different tissues impacted crossmatch outcomes. HLA expression is impacted by multiple factors and should be routinely monitored to ensure crossmatch sensitivity and to reconcile crossmatch strength with solid phase HLA antibody analyses.     

The role of HLA antibodies in neonatal thrombocytopenia: a prospective study

The role of HLA antibodies in neonatal alloimmune thrombocytopenia is controversial. We prospectively studied the sera of obstetric patients at delivery for HLA antibodies and correlated their presence with umbilical cord blood platelet counts. We studied 493 births at The Johns Hopkins Hospital comprising of 357 African American, 115 Caucasian, and 21 babies of other racial groups. One hundred and thirty nine mothers had HLA antibodies. Of these HLA alloimmunized mothers, only ten infants had platelet counts of 150,000/μL or less. Three hundred and eight mothers with no detectable antibodies gave birth to 27 infants with platelet counts of 150,000/μL or less. Yates corrected Chi square analysis showed no significant relationship between maternal HLA alloimmunization and baby platelet count (p=0.709). Only 8 of sixty cord sera from babies of HLA alloimmunized mothers were positive for HLA antibodies. The HLA cord blood antibody results were then correlated with the neonatal platelet counts. The Fisher's exact test showed no significant relationship between the presence of HLA antibodies in cord blood samples and neonatal platelet counts (p=0.232). Although one third (31%) of mothers have HLA antibodies, neonatal thrombocytopenia is rarely associated with this finding. However, HLA antibodies can cross the placenta, and in these unusual cases, may be associated with a higher risk of neonatal thrombocytopenia.     

Anti-neutrophil cytoplasm antibodies in rheumatoid arthritis.

Anti-neutrophil cytoplasm antibodies (ANCA) occur occasionally in rheumatoid arthritis (RA), but their incidence and clinical significance have been unclear. In this study we have investigated 58 patients with RA. In 22 patients the disease was inactive and the remaining 36 with active disease were further subdivided into those without clinical evidence of vasculitis (26), those with cutaneous vasculitis (8) and those with systemic vasculitis (2). ANCA were demonstrated by indirect immunofluorescence in 10 of the 58 patients (17%). While both perinuclear (pANCA) and cytoplasmic (cANCA) staining were detected, pANCA were more common (70%). Neutrophil-specific anti-nuclear antibodies (ANNA) were demonstrated in a further eight sera (14%) and ANA were detected on Hep-2 cells in 30 of the 58 sera (52%). ELISAs for the detection of anti-myeloperoxidase and anti-elastase antibodies were then established. Five sera with pANCA and five that contained ANNA were negative for both anti-myeloperoxidase and anti-elastase antibodies, suggesting other as yet unidentified cytoplasmic antigens as the target molecules. However, anti-myeloperoxidase or anti-elastase antibodies were found in four sera that had homogeneous or speckled ANA on both Hep-2 cells and neutrophils. One serum contained both antibodies. The presence of ANCA detected by indirect immunofluorescence or of anti-myeloperoxidase or anti-elastase antibodies in these patients with RA was not associated with disease activity nor with the demonstration of cutaneous vasculitis or renal disease (P NS). A possible association with systemic vasculitis remains to be confirmed. There is an incomplete correlation between indirect immunofluorescence patterns and antibody specificity in ELISA systems.     

广东汉族人类风湿关节炎易感性与HLA-DRB1基因相关性研究

目的探讨ＨＬＡ－ＤＲＢ１基因与类风湿关节炎（ＲＡ）相关性。方法采用ＰＣＲ－ＳＳＰ方法对４７例广东汉族人ＲＡ患者进行ＨＬＡ－ＤＲＢ１基因分型，并与相应人群健康者１０２例结果比较。结果ＨＬＡ－ＤＲ４基因在ＲＡ组显著增高（３５．１％，ＲＲ＝３．５５，Ｐ＜０．００５，ＥＦ＝０．２５２），ＤＲ１６在ＲＡ组也高于正常（ＲＲ＝２．５７，Ｐ＜０．０５）；而ＤＲ９基因在ＲＡ组显著减少（Ｐ＜０．００５）。３１例ＤＲ４＋患者患病年龄较早，病情较重（类风湿因子阳性率和Ⅱ期ＲＡ骨关节Ｘ线改变者显著高于ＤＲ４－患者，Ｐ值分别＜０．０５和０．０２５）。结论广东汉族人ＲＡ易感性与宿主ＤＲ４基因密切相关，ＨＬＡ－ＤＲ４可能是一个对判断病情和预后有价值的实验指标。     

The production of human monoclonal autoantibodies from patients with rheumatoid arthritis by the EBV-hybridoma technique

Rheumatoid lymphocytes tend to transform 'spontaneously' in vitro because of prior infection with Epstein Barr virus (EBV). They are particularly difficult to use in experiments involving cell hybridisation, because in the conventional half-HAT system unfused transformed cells may be confused with hybrids. We describe how the HAT-sensitive, ouabain-resistant human B lymphoblastoid cell line KR4, originally developed to 'rescue' EBV induced B cell clones, can be fused successfully with peripheral blood lymphocytes from patients with rheumatoid arthritis to produce unequivocal hybrids.     

Correlative studies of rheumatoid factors and anti-viral antibodies in patients with rheumatoid arthritis.

An analysis of the relationship between the immune response to ubiquitous herpes family viruses, namely Epstein-Barr virus (EBV), cytomegalovirus (CMV), and varicella-zoster virus (VZV) and the presence of rheumatoid factors (RF), which are autoantibodies characteristic of patients with rheumatoid arthritis (RA), was conducted. Antibody profiles (RF, anti-viral antibodies) were monitored in the serum of the RA patients, and in normal individuals. No patient was found to have circulating RF in the absence of anti-viral antibodies. When the patients and normal controls were subdivided according to the presence of serum RF, it was found that when RF were present, the frequency of anti-CMV antibodies, but not anti-EBV or anti-VZV antibodies, was significantly higher (P = 0.02) when compared with RF-negative individuals. The titres of anti-CMV but not anti-VZV antibodies were found to increase in the RA patients with disease duration. To see if these viruses could stimulate RF production in vitro, peripheral blood mononuclear cells (PBMC) isolated from the patients and normal controls were stimulated with viral antigens. PBMC from normal controls, but not from RA patients, appeared to be responsive to viral antigen stimulation and produced RF. These data suggest that the immune response to CMV, to a greater extent than to EBV or VZV, correlates with the presence of RF.