FIG 5 .

Failure of the CHIKV Opal524R mutant to induce severe disease is associated with low immune cell infiltration. (A, B) C57BL/6J mice were infected at 24 days old in the left rear footpad with 100 PFU of wild-type CHIKV or the Opal524R mutant or mock infected with diluent (6 per group). At 7 days postinfection, mice were sacrificed and perfused intracardially with 1× PBS. The ipsilateral foot was harvested and processed for analysis by flow cytometry. Recruitment of the indicated inflammatory leukocyte populations was measured and expressed as either total cell counts per foot (A) or percentage of LCA⁺ cells (B). Data are representative of two independent experiments. Individual data points, which are represented by a solid dot, represent outliers. These are defined as values that exceed the third quartile plus 1.5 times the interquartile range (IQR) or fall below the first quartile minus 1.5 times the IQR. Statistical significance is indicated as follows: *, P < 0.05, and **, P < 0.01.