HLA-D ALLELES ASSOCIATED WITH GENERALIZED DISEASE, LOCALIZED DISEASE,AND PUTATIVE IMMUNITY IN ONCHOCERCA-VOLVULUS INFECTION

Human infections with the tissue nematode Onchocerca volvulus result i n a variety of clinical conditions that possibly include protective im munity. In a West African area hyperendemic for human onchocerciasis, 120 residents were classified according to clinical and laboratory fin dings as presenting with generalized onchocerciasis, localized onchoce rciasis, or as being putatively immune. The three groups differed in t he distribution of HLA-D variants as determined by DNA typing. The mos t pronounced differences were found among alleles of the DQ loci. The haplotype DQA10501-DQB1*0301 was significantly more frequent among pu tatively immune individuals than among patients with generalized or lo calized disease. Conversely, DQA10101-DQB1*0501 and, independently, t he allele DQB10201 were more frequent in generalized disease than in localized disease or putative immunity. In these correlations, the fre quencies of allelic variants were in localized disease intermediate to those of the two other groups. The only distinct association found wi th localized disease was that of the DP allele DPB10402. The findings indicate that HLA-D variants influence the course of 0. volvulus infe ction and help to define a state that may reflect protective immunity.