[Variations under genetic control of onchocerca infection as a function of clinical profile in the endemic center of Cameroon].
Onchocerciasis, also known as "river blindness", presents a plenum of clinical manifestations which vary from one individual to another, and from one area to another. This large spectrum of clinical manifestations of the disease is an indication of the complexity of the pathogenesis of onchocerciasis and suggests that many interacting factors might influence the clinical features of the disease. The present study has focused on the heterogenicity of the host immune response as a plausible explanation for differences in clinical manifestations of the infection. Host genetic factors, namely HLA genes, might play an important role in determining the nature of the immune response mounted against the parasite Onchocerca volvulus, and thus the development of different manifestations of the infection. Genetic diversity of onchocerciasis was assessed in different endemic foci in Cameroon. In order to investigate the possibility that the Major Histocompatibility Complex (MHC) genes might be associated with the different clinical types of onchocerciasis, 146 subjects living in three endemic areas of Cameroon were studied. They were classified in four groups: A (asymptomatic subjects), P (putatively immune subjects) L (patients with localised disease) and G (patients with generalised disease). The four groups differed in the distribution of HLA class II alleles as determined by Direct Heteroduplex Analysis. On the one hand, allele HLA-DQA1*0501 appeared to be associated with protection against severe onchocerciasis; on the other, allele HLA-DQB1*0201 might play an important role in the severe form of the disease.
Laboratoire d'immunologie, Faculté de médecine et des sciences biomédicales, Yaoundé, Cameroun.
J
J
Donfack
J L
JL
Ngu
G
G
Lando
P A
PA
Zimmerman
J
J
Nutman
A
A
Same-Ekobo
D000483:Alleles; D002163:Cameroon / Q000453:epidemiology; D004247:DNA / Q000032:analysis; D019353:Endemic Diseases; D006683:HLA-DQ Antigens / Q000235:genetics; D059848:HLA-DQ alpha-Chains; D059866:HLA-DQ beta-Chains; D000949:Histocompatibility Antigens Class II / Q000235:genetics*; D006801:Humans; D009855:Onchocerciasis / Q000453:epidemiology / Q000235:genetics* / Q000276:immunology*
D006683:HLA-DQ Antigens; D059848:HLA-DQ alpha-Chains; D059866:HLA-DQ beta-Chains; C069050:HLA-DQA1 antigen; C069051:HLA-DQB1 antigen; D000949:Histocompatibility Antigens Class II; D004247:DNA
Variations sous contrôle génétique de l'infection onchocerquienne en fonction du profil clinique dans les foyers endémiques du Cameroun.