Adherent peritoneal mononuclear cells express chloroacetate esterases in vitro.

Murine peritoneal adherent mononuclear cells elicited by intraperitoneal glass implants express nonspecific esterases (alpha-naphthyl acetate esterases) as demonstrated by enzyme histochemical methods. After nine days of in vitro culture, 50% of cells obtained from normal mice and 100% of cells obtained from schistosome-infected mice expressed chloroacetate esterases (naphthol AS-D chloroacetate esterases). Fifty percent of the cells from normal mice continued to present nonspecific esterase activity, whereas cells from infected mice presented only chloroacetate esterase activity. This modulation of esterase expression can be interpreted to be a reflection of in vitro cell differentiation.