Fig. 5.

MC-dependent recruitment of NK and NKT cells to site of DENV injection. Relative numbers of NK1.1⁺ CD3⁻ (A) and NK1.1⁺CD3⁺ (B) cells after infection are increased over saline control tissues in WT and Sash-R mice but decreased in Sash mice, resulting in a significantly reduced fold increase for Sash mice compared with MC-sufficient mice (*P < 0.01; n = 4–6). (C) Microscopy of a footpad section 24 h after injection of 2 × 10⁵ pfu of DENV2 shows that MCs (green) are activated in the vicinity of a recruited NK1.1⁺ (red) and CD8⁺ (blue) cell, based on the presence of proximal extracellular granules (boxed in green in C). A larger magnification of the surrounding tissue is included as Fig. S7. (D) Staining for CD31 (blood vessels; red), MC granules (green), and NK1.1⁺ cells (blue) demonstrates that NK1.1⁺ cells are found within the tissue in areas of MC activation in MC-sufficient mice at 24 h after injection of 1 × 10⁵ pfu of DENV2 but not in uninfected (WT control) or DENV-infected Sash mice. (Magnification in C and D: 20× by confocal microscopy.)