Paramyxovirus membrane protein augments the antibody response to actin in mice.

The production of anti-actin antibodies has been studied in mice. Not one of 10 mice immunized with native actin produced anti-actin antibodies, whereas seven out of 10 mice immunized with actin mixed with paramyxovirus membrane (M) protein produced a high titre of antibodies to actin. The enhancement of anti-actin antibody production by M protein is specific to actin since antibodies to protein purified derivatives (PPD) or gelatin were not enhanced by M protein. The enhanced anti-actin antibodies depended upon the interaction of actin and M protein since injection of M protein and actin in separate sites failed to produce anti-actin antibodies. Five Balb/c nude mice immunized with actin and M protein failed to produce anti-actin antibodies suggesting that cell-mediated immune response is also required for this response.