How HIV-1 lentivirus causes immune deficiency disease.

Human immunodeficiency virus (HIV-1) associated immune deficiency has the characteristics of chronic graft versus host disease (GVHD) caused by human leukocyte antigen (HLA) class 2 incompatibility. The envelope glycoprotein fragment TKAKRRVVEREKR mimics HLA class 1 C molecules serologically, and also mimics an immune regulatory T cell epitope, in the region of amino acids 67 to 71, within the HLA DR beta chain. This beta chain alloepitopic region (between amino acids 67 to 80) furnishes peptides predicted to bind optimally to HLA class 1 B alleles. The hypothesis predicts that viral parameters, such as viral load, and clinical parameters, such as rate of progress to acquired immune deficiency syndrome (AIDS) and severity of the associated immune deficient state, are linked to the HLA B and HLA DR beta chain haplotype in infected patients. Immune suppression is caused by HLA class 1 B restricted CD8+ T cells which normally regulate HLA class 2 DR restricted antigen specific responses. The hypothesis further predicts the severity of immune deficiency to be linked to those HLA DR beta chain allotypes which express the amino-acid glutamine (Q) in position 70.