Fig 8.

Whole-cell EhMSP-1 abundance versus surface exposure as assessed by flow cytometry. E. histolytica trophozoites harvested after 24 h of culture were fixed, permeabilized (A) or not permeabilized (B) with 0.2% Triton X-100, and stained with either anti-EhMSP-1 rabbit polyclonal IgG or preimmune rabbit IgG followed by an anti-rabbit IgG–Alexa 488 conjugate. EhMSP-1 staining was assessed by flow cytometry. Representative fluorescence-activated cell sorting histograms are shown. (A) Permeabilized trophozoites showing whole-cell staining of EhMSP-1. EhMSP-1 abundance had a normal distribution. (B) Nonpermeabilized trophozoites showing staining of cell surface EhMSP-1. Distinct populations with high and low surface EhMSP-1 exposure were evident.