An Electron Microscopic Study of Penetration by Trypanosoma rangeli into Midgut Cells of Rhodnius prolixus

Penetration of the salivary glands of Rhodnius domesticus Neiva & Pinto, 1923 (Hemiptera: Reduviidae) by Trypanosoma rangeli Tejera, 1920 (Protozoa: Kinetoplastida)

“…In vitro studies on the interaction of T. rangeli with dissected fragments of the posterior midgut of R. prolixus showed few parasites attached to sparse epithelial cells, suggesting that a recognition step is necessary for posterior invasion (Oliveira and De Souza 2001). This behavior has also been observed in other insect-protozoan models, such as Plasmodium gallinaceum infecting Aedes aegypti, where the parasites were found associated preferentially with a well-defined cell type (Shahabuddin and Pimenta 1998).…”

“…Damaged areas of intestinal epithelium in R. prolixus infected with T. rangeli have been reported (Watkins 1971). It has been recently suggested that the parasites transverse the cytoplasm of the midgut cells, causing cell damage (Oliveira and De Souza 2001). However, it has been also proposed that T. rangeli cross the intestinal barrier by an intracellular route without damaging the cells (Hecker et al 1990).…”

“…Ultrastructural studies on the penetration of T. rangeli into midgut cells (Hecker et al 1990;Oliveira and De Souza 2001) and salivary glands (Ellis et al 1980) of Rhodnius prolixus have been carried out, but the mechanisms used by the trypanosomes to penetrate and transverse these structured epithelia are controversial. Damaged areas of intestinal epithelium in R. prolixus infected with T. rangeli have been reported (Watkins 1971).…”

Trypanosoma rangeli interactions within the vector Rhodnius prolixus: a mini review

“…In the process of interaction of T. rangeli with gut epithelial cells of R. prolixus, the parasites attach to the surface of some epithelial cells either through the flagellum, mainly in the areas of contact between two epithelial cells, or through the posterior end of the protozoan, especially to the perimicrovilar membranes and penetrate into cells that show less dense cytoplasm organelles (Oliveira & Souza 2001). The ultrastructural disorganization of the midgut epithelial cells, mainly the perimicrovillar membranes and microvilli, facilitates T. rangeli invasion of the hemolymph (Gomes et al 2002).…”

“…The flagellates pass through the gut epithelium by intracellular route (Hecker et al 1990). After damaging the surface, the parasite moves within the cytoplasm of the epithelial cell, reaches the basal region, crosses the basal lamina, and enters into the hemocoel (Oliveira & Souza 2001). However, the penetration rate of the gut is low, only less than 10% of parasites pass through the gut cell wall (Hecker et al 1990).…”