In vivo administration of monoclonal antibody to the NK 1.1 antigen of natural killer cells: effect on acute murine cytomegalovirus infection.

Monoclonal antibody to the NK 1.1 antigen, found on the natural killer cells of a number of strains of mice, specifically suppresses NK cell function when given in vivo. Using this monoclonal antibody, we have examined the effects of specific suppression of natural killer (NK) cells in vivo on acute murine cytomegalovirus (MCMV) infection in C57BL/10ScN mice. Administration of antibody to NK 1.1 substantially lowered the resistance of C57BL/10ScN mice to lethal virus challenge. In addition, antibody administration prior to intraperitoneal infection significantly increased MCMV replication in salivary glands, lungs, and spleens. In C3H/HeN mice, a strain that lacks the NK 1.1 antigen, antibody to NK 1.1 had no effect on virus replication or lethal infection. Thus, in vivo administration of monoclonal antibody to NK 1.1 alters the course of acute MCMV infection. These findings further substantiate the role of NK cells in defense against acute MCMV infection.