A comparison of nonopsonic and opsonic PE phagocytosis.

PEs were prepared as before or were opsonized by the addition of malarial patient antiserum for 60 minutes. Phagocytosis was allowed to proceed for 4 hours, at which time nonadherent cells were washed away and adherent erythrocytes lysed. The phagocytic index for the 2 groups was calculated as described in “Materials and methods.” Data = mean ± SEM; n ≥ 8 per group. δ, P < .001 vs control UEs; ***, P < .001 vs nonopsonized PEs (ANOVA with post hoc Tukey).