Histocompatibility antigens and cell-mediated immunity in carriers of hepatitis B virus; a study of a family.

The cause of the HBsAg carrier state is unknown, and environmental genetic and immunologic factors have been implicated. Herein, a family is described in which the carrier state was associated with the HLA-A28BW15 haplotype and with impaired cell mediated immunity. The relevance of the genetic marker in this family is uncertain. It could be associated with a genetic susceptibility to the virus or alternatively with inherited immunodeficiency. According to the first possibility the impaired immunity could be secondary to the persistent viral infection. According to the second one the acquisition of the carrier state could result from the inherited immune defect.