THE AMOUNT OF HOST HLA-DR PROTEINS ACQUIRED BY HIV-1 IS VIRUS-STRAIN-SPECIFIC AND CELL-TYPE-SPECIFIC

We semiquantitatively monitored the incorporation of host membrane pro teins on different strains of human immunodeficiency virus type 1 (HIV -1) grown in several human CD4+ lymphoid cell lines and in primary mit ogen-stimulated peripheral blood mononuclear cells. The relative amoun ts of virally acquired cell proteins were estimated by the ability of HIV-1 to be captured by magnetic beads coated with monoclonal antibodi es. Here we report that, among host surface proteins studied, HLA-DR m olecules were the most abundant virion-bound host molecules. We have a lso found that, in contrast to previous studies, HLA-DP and -DQ isotyp es were also present on virus progeny. More importantly, we determined that the relative levels of virally acquired host HLA-DR proteins, as estimated by capture with immunomagnetic beads, greatly differed depe nding on the Virus strain and the producer cell. These observations ex tend beyond already published results and suggest that the process of incorporation of cellular molecules on newly released virus particles is a phenomenon that relies on both the virus strain and producer cell line. These in vitro observations are of prime importance considering that virus-acquired host molecules have been recently shown to affect the biology of HIV. (C) 1996 Academic Press, Inc