title: A monocyte chemotaxis inhibiting factor in serum of HIV infected men shares epitopes with the HIV transmembrane protein gp41.
abstract: This report describes that gp41, the transmembranous envelope protein of HIV, is able to inhibit monocyte chemotaxis (measured as FMLP-induced polarization). To study the presence of such immunosuppressive HIV env proteins in the circulation of HIV-infected men, fractions were prepared from serum via ultrafiltration, yielding molecules with a relative Mr of 25-50. These fractions inhibited FMLP-induced polarization of normal human monocytes, while similar fractions of HIV-uninfected men did not. A monoclonal antibody (MoAb) to gp41 was able to adsorb the serum factor responsible for this inhibitory activity. This demonstration of the presence of a gp41-like factor in the circulation of HIV-infected men exerting immunosuppressive activities might have implications for the understanding of the pathogenesis of AIDS, as well as for the selection of HIV-encoded proteins for putative vaccines.
mesh_terms: D000163:Acquired Immunodeficiency Syndrome / Q000276:immunology*; D000328:Adult; D000911:Antibodies, Monoclonal; D002634:Chemotaxis, Leukocyte / Q000187:drug effects; D000939:Epitopes / Q000032:analysis; D015700:HIV Envelope Protein gp41; D006801:Humans; D007108:Immune Tolerance; D008222:Lymphokines / Q000097:blood*; D008297:Male; D009000:Monocytes / Q000502:physiology*; D009240:N-Formylmethionine Leucyl-Phenylalanine / Q000494:pharmacology; D012191:Retroviridae Proteins / Q000097:blood*; D014759:Viral Envelope Proteins / Q000097:blood*
chemical_list: D000911:Antibodies, Monoclonal; D000939:Epitopes; D015700:HIV Envelope Protein gp41; D008222:Lymphokines; D012191:Retroviridae Proteins; D014759:Viral Envelope Proteins; C034397:chemotactic inhibitory factor; D009240:N-Formylmethionine Leucyl-Phenylalanine