Serum antibodies to HIV-1 are produced post-measles virus infection: evidence for cross-reactivity with HLA.

Convalescent sera obtained from patients who were recently recovered from an acute measles virus infection were tested for the presence of anti-HIV-1 antibodies by Western blot analysis. While 16% (17/104) of control sera displayed reactive bands to a variety of HIV proteins, 62% (45/73) of convalescent sera demonstrated immunoreactive bands corresponding to HIV-1 Pol and Gag, but not Env antigens. This cross-reactivity appears to be the result of an active measles infection. No HIV-1 immunoblot reactivity (0/10) was observed in sera obtained from young adults several weeks after a combined measles, mumps, and rubella (MMR) vaccination. Interestingly, examination of anti-HLA typing sera specific for either class I and class II molecules revealed that 46% (19/41) of these sera contained cross-reactive antibodies to HIV-1 proteins. Absorption of measles sera with mixed lymphocyte reaction (MLR)-activated lymphocytes and/or HIV-1 recombinant proteins significantly decreased or removed the presence of these HIV-1-immunoreactive antibodies. Together, these findings suggest that the immune response to a natural measles virus infection results in the production of antibodies to HIV-1 and possibly autoantigens.