Relationship of Flexibility and Resilience with Islamic Work Ethics

Abstract

We monitored the distribution of Plasmodium falciparum circumsporozoite protein (CS) in Anophdesstephensi using an immunohistochemical method. An alkaline phosphataselabeled monoclonal antibody, specific for the CS protein of P Ilı1ciparum, was incubated with tissue sections from infected and non-infected mosquitoes. Sections were stained for phosphatase activity using a new fuchsin/naphtholAS-BI phosphate capture system. Distribution of the CS protein in mosquitoes was dependent on the time after post-infective blood meal. CS protein was first detected in immature oocysts on the mosquito midgut. As oocysts differentiated to mature sporoblasts, detectable CS protein increased. Between Introduction The human malarial parasite Plasmodium falciparum undergoes fertilization and sporogony in the mosquito. During a blood meal, the mosquito ingests the male and female gametocytes from the the malaria-infected human host. Fertilization occurs in the midgut of the mosquito, producing a zygote which rapidly differentiates to an elongated motile ookinete. The Pfalczparum ookinete traverses the midgut wall by an intercellular route between epithehial cells (Meis and Ponnudurai, 1987). Beneath the basement membrane the ookinete rounds up, forming an oocyst which quickly undergoes reduction division. The oocyst differentiates, producing sporozoites which invade the salivary glands and can be transmitted to a human host via a mosquito bite. The surface of the sporozoite is covered by the circumsporozoite (CS)protein, the primary antigen used in the development of malarial sporozoite vaccines (Ballou et al., 1987). The CS protein of several Plasmodium species has been detected in maturing oocysts (Boulanger et al., 1988; Hamilton et al., 1988; Nagasawa et al., 1 Supported in part by the UNDP/World Bank/WHO Special Programme for Research and Training in Tropical Diseases. The views of the authors do not purport to represent the position of the Department of the Army on the Department of Defense. 2 To whom correspondence should be addressed. 11-16 days post infective blood meal, CS protein was detected on the surface of sporozoites that were released into the hemolymph from oocysts. Although sporozoites were found throughout the hemocoel, they were most frequently associated with the salivary glands and flight muscle. Once inthe salivary glands, sporozoites massed into bundles. The amount ofCS protein associated with bundles of sporozoites was highly variable. (J Histochem Cytochem 38:475-481, 1990)