Distribution of iNOS+ cells in inflammatory foci after infection with thermally preinduced Y. pestis.

aWithin each focus size, the percent having each distribution of stained cells is given, and the actual number of foci in each category is in parentheses.bFoci were measured in their largest aspect and classified as small (100 µm).cThe presence of stained cells within the central part of the focus identified that lesion as having a Central (Cent.) distribution. This distribution tended to have iNOS+ cells scattered over the focus, often resembling a lattice. If the cells were seen only in a ring around the perimeter extending inward not more than 25% of the diameter of the focus, the distribution was designated as Edge. iNOS+ cells also demonstrated an “invasive” localization (Inv.), appearing internal to the outer 25% of diameter as well as in the edge but not in the center. Foci with no iNOS+ cells are designated “None”.dLivers from 3 mice per strain were analyzed in one experiment; 2 mice per strain were analyzed in the other. The distributions of iNOS+ cells for medium foci between infections by the two Y. pestis strains were significantly different by Fisher's exact test (two-tailed p = 0.043; calculated using the online tool at quantitativeskills.com/sisa/statistics/fiveby2.htm). The distributions for small and large foci did not differ significantly.Distribution of iNOS+ cells in inflammatory foci after infection with thermally preinduced Y. pestis.