Antigen Incorporation on Cryptosporidium parvum Oocyst Walls

Mem Inst Oswaldo Cruz 2001, Volume 96, Number 2, pp. 233-235 Antigen Incorporation on Cryptosporidium parvum Oocyst Walls Emilio Entrala+, Younes Sbihi, Manuel Snchez-Moreno, Carmen Mascar Code Number: oc01033 ABSTRACT: Cryptosporidium parvum oocysts are the infective stages responsible for transmission and survival of the organism in the environment. In the present work we show that the oocyst wall, far from being a static structure, is able to incorporate antigens by a mechanism involving vesicle fusion with the wall, and the incorporation of the antigen to the outer oocyst wall. Using immunoelectron microscopy we show that the antigen recognized by a monoclonal antibody used for diagnosis of cryptosporidiosis (Merifluor, Meridian Diagnostic Inc.) could be found associated with vesicles in the space between the sporozoites and the oocysts wall, and incorporated to the outer oocyst wall by an unknown mechanism. KEYWORDS: Cryptosporidium, oocyst wall, antigen Copyright 2001 Fundacao Oswaldo Cruz Fiocru