Summary:Cellular proteins, including major histocompatibility complex (MHC) class I and class II antigens, are incorporated into the membrane of HIV-1 when virions bud from infected cells. Experiments were performed to determine whether human sera that contained MHC class I and/or class II antibodies would lyse or neutralize a primary isolate of HIV. These results demonstrate that in the presence of complement, sera from some alloimmunized persons mediated significant anti-viral activity against an HIV primary isolate. Both lysis and neutralization of virus were observed. The antiviral effects were complement dependent because heat inactivation eliminated most anti-viral effects. Antiviral activity mediated by sera containing MHC alloantibodies in the presence of complement was ≥ activity due to sera from HIV-infected persons as reported in this and a previous study. High levels of antibodies to both MHC class I and class II were present in sera that mediated the highest levels of antiviral activity. Absorption of serum with platelets (which express class I but not class II antigens) substantially reduced their lytic activity. These studies suggest that MHC antibodies mediate potent anti-viral effects on primary isolates of HIV and support the possibility that deliberately alloimmunizing humans might protect against HIV infection.
Address correspondence and reprint requests to Gregory T. Spear, Department of Immunology/Microbiology, Rush-Presbyterian-St. Luke's Medical Center, 1653 W. Congress Parkway, Chicago, IL 60612 U.S.A.; e-mail: firstname.lastname@example.org
Manuscript received August 16, 2000; accepted September 29, 2000.
© 2001 Lippincott Williams & Wilkins, Inc.