Murine Cytomegalovirus Is Regulated by a Discrete Subset of Natural Killer Cells Reactive with Monoclonal Antibody to Ly49h

Daniels, Keith A.; Devora, Gene; Lai, Wayne C.; O'Donnell, Carey L.; Bennett, Michael; Welsh, Raymond M.

Stimulation of 1F8 ϩ Cells by Other Viruses. We tested whether the profound stimulation of Ly49H ϩ NK cells was unique to MCMV or whether it was a general property of viral infections. As with MCMV infection, the proportions of 1F8 ϩ NK cells and of Ly49H ϩ (1F8 ϩ , 5E6 Ϫ ) NK cells increased in the organs of mice infected with LCMV clone 13, MHV, or VV. In one experiment, 17% of the resident PEC NK cells were 1F8 ϩ 5E6 Ϫ , and this increased to 31, 29, and 37% 2 d after infection with LCMV, MHV, and VV, respectively (Fig. 6 ); 6.7% of the resident NK cells in the liver were 1F8 ϩ 5E6 Ϫ , and this, respectively, increased to 36, 35, and 40% by 2 d after infection. LCMV and MHV were also examined at 3 d after infection and similarly induced higher levels of 1F8 ϩ 5E6 Ϫ (Ly49H)-positive cells in the PECs and liver by 3 d after infection (data not shown). Thus, this NK cell subset, presumed to be Ly49H ϩ , appeared to respond well to all tested virus infections.