[Antigens A and B of the HLA system in dilated cardiomyopathies related to alcohol]. / Etude des antigènes A et B du système HLA dans les myocardiopathies dilatées liées à l'alcool.

It has been hypothesized that dilated cardiomyopathy (DCM) is of dysimmune origin. Conventional immunological studies have provided no evidence that a primary disregulation of immune mechanisms is involved. In the present study, the possibility of an individual predisposition to DCM resting on a preferential distribution of HLA system antigens has been investigated. Typing of the HLA system antigens A and B was performed in a group of 38 DCM patients who were heavy drinkers. The results were compared with those obtained in: (a) 57 alcoholic patients without cardiopathy, and (b) a population of 306 healthy subjects. All subjects were caucasians. Compared with alcoholic patients without cardiac disease, DCM patients had a prevalence of B8 allele. The relative risk of developing DCM was 2.83 in the presence of the B8 antigen. This result suggests a genetic predisposition to DCM: the B8 allele, prevalent among our patients, is associated with the phenotype of numerous autoimmune diseases. This study therefore supports the theory that DCM is of dysimmune origin, but this must be confirmed by further investigations conducted on a larger number of cases.

[Study of HLA antigens A and B and their cross reactions in B27-negative ankylosing spondylarthritis]. / Etude des antigènes HLA A et B et de leurs réactions croisées dans la spondylarthrite ankylosante B27 négative.

In an attempt to find common immunogenetic features in B27+ and B27- ankylosing spondylitis patients, the B7 cross reactant antigens (BW22, B27, B40, B12, B13) were systematically tested by a lymphocytotoxicity method in 43 patients suffering from ankylosing spondylitis according to the Rome criteria. These included 25 caucasian patients (20 B27+, 5 B27-), 15 north african patients (11 B27+, 4 B27-) and 3 west indian mulattos (all B27-). The frequency of the B7 cross reactant antigens, when compared to controls, was not increased in the B27- patients as a whole, nor in any of the 3 populations studied. Our negative results are in agreement with those of similar published studies in homogeneous populations. They do not support the hypothesis of a direct involvement of HLA B antigens as cofactors favouring ankylosing spondylitis.

[Cross reactions of HLA A and B antigens in 63 patients with rheumatoid arthritis]. / Etude des réactions croisées des antigènes HLA A et B chez 63 patients atteints de polyarthrite rhumatoïde.

Cross reactions are very frequently observed when HLA A and B antigens are determined by a routine lymphocytotoxicity method. Such cross reactions are probably due to biochemical structural similarities shared by several HLA antigens. In this work, we studied the cross reactions which occurred during HLA A and B typing of 63 patients with classical or definite rheumatoid arthritis (RA) according to the ARA criteria. No association was found between RA and any single HLA A or B antigen. In contrast, when cross reactions were taken into account, the B8 B14 cross reactant group frequency was increased in RA patients (34,9 p. cent) as compared to controls (20 p. cent, p less than 0,004) and was even more clearly elevated in the 42 seropositive RA patients (40,5 p. cent, p less than 0,002). No relation was found between HLA phenotype and Sjögren's syndrome even when cross reactions were considered. The B8 DR3 haplotype has been shown to be associated with drug intolerance . The B8 B14 cross reactant group was present in 22 out of our 63 RA patients, 16 of whom were B8+. Among the latter, 6 patients exhibited poor tolerance to gold salts and 6 other patients did not respond to gold therapy, suggesting that the B8 antigen could predict not only a poor tolerance but also a poor response to disease modifying drugs.