Similar to what we found in IL-17–/– PCP mice, we noted that CD4+ T cells (10.0 ± 1.5 vs 6.5 ± 0.9%, P < 0.01, Figure 4(d)) and γδT cells (35.2 ± 2.1 vs 16.5 ± 1.6%, P < 0.01, Figure 4(e)) were expressing more IL-17 in the lung from IL-10–/– PCP mice than WT PCP mice. The gene discussed is IL17A; the disease is pneumocystosis.