Genomic diversity of the acquired immunodeficiency syndrome retroviruses is reflected in alteration of its translational products

Abstract

We have isolated retroviruses from six acquired immunodeficiency syndrome (AIDS) and three lymphadenopathy syndrome (LAS) patients by cocultivation of patients' lymphocytes with phytohemagglutinin-stimulated normal T cells. In an effort to address the extent to which these viruses have identical genetic information or there is divergence in their genomic sequences, we have compared the nine retrovirus isolates by the following criteria: (i) antigenic cross-reactivity by highly specific and sensitive competition radioimmunoassay for the major internal antigen; (ii) restriction site mapping analysis; and (iii) immunoblot analysis and metabolic labeling of viral structural proteins and their analysis by polyacrylamide gel electrophoresis. The data indicate that individual retroviruses have significant restriction site polymorphism in their genome even though they were isolated from patients residing at one geographic location. Furthermore, this polymorphism is reflected in the variation of the apparent size of the gag and env gene-encoded structural proteins. The heterogeneity in AIDS retrovirus-encoded proteins may be due to either substitutions in the primary amino acid sequence of the protein or deletions or additions in the coding regions of proteins. The alterations in viral structural proteins among various AIDS retroviruses could have important implications in antigenic properties and/or pathogenicity in development of the disease, its detection, and ultimately its eradication.