MCMV activates Ly49H⁺ NK cells and expands Ag-specific CD8⁺ T cells from Siglec-H^−/− and wt mice with similar viral clearance in the primary and secondary organs.

Siglec-H^−/− and wt chimeric mice were infected with 5×10⁴ PFU of wt MCMV or mock treated with PBS. (A, B) IFNγ serum concentrations were determined at 36 h p.i. and the MFI of CD69 expression on NK1.1⁺ blood NK cells was quantified by flow cytometry. (C, D) Representative histogram overlays and quantification of KLRG-1 expression on splenic NK1.1⁺ Ly49H⁺ cells at day 8 p.i. (E) Representative FACS plots for H-2D^b M45 tetramer staining and CD62L expression among CD8⁺ splenocytes. (F, G) Quantification of frequencies and absolute numbers of tetramer⁺ CD8⁺ T cells from the tetramer staining shown in (E). (H) Shows frequencies of IFNγ⁺ cells among CD8⁺ T cells after restimulation with the indicated concentrations of H-2D^b M45 peptide. (I) Viral load was measured in the spleen, liver and salivary glands of MCMV infected Siglec-H^−/− and wt mice at day 3, 6 and 8 p.i. Dashed line indicates the limit of detection. Data shown are pooled from 2–3 individual experiments. **p<0.01 Students t-test, ns = not significant, nd = not detectable.