Cytological Studies on the Intestinal Epithelial Cells of Ascaris lumbricoides suum

Histochemical and fine structure observations of the intestinal epithelium ofTrichuris suis (Nematoda: Trichuroidea)

“…Aspiculuris tetraptera and Enterobius vermicularis (Anya, 1964) and A. lumbricoides var. suum (Kessel et al, 1961) has also been shown to be PAS positive. The intestinal lumen of T. suis contained PAS positive material and tiny droplets which were stained with Alcian-blue.…”

“…Cytoplasmic fragments and calcareous corpuscles were occasionally detected in the lumen. Andreassen (1968) recorded occasional blebs protruding into the intestinal lumen of P. decipiens and also Kessel et al (1961) described the formation of blebs between the microvilli and suggested they might contain materials being secreted into the gut lumen. It would appear from this series of fine structure observations that these cytoplasmic extrusions portray an underlying mechanism resembling merocrine secretion whereby the cytoplasmic components of certain intestinal cells are discharged into the lumen.…”

“…(Jenkins and Erasmus, 1969). Earlier, Kessel et al (1961) reported secretory blebs in the intestinal epithelium of Ascaris suum and Wright (1963) drew attention to a potential secretory role in another trichuroid,…”

Intestine ultrastructure of the facultative parasite Halicephalobus gingivalis (Nematoda: Panagrolaimidae)

“…The general structure of the intestine appears quite uniform, with the exception of some marine (e.g., Miljutin & Tchesunov, 2001;Miljutin et al, 2006) and plant-parasitic taxa (Geraert, 1992). The intestine is a straight tube which comprises a limited number of cells organised in a single layer with a luminal surface that is lined with microvilli which mostly have a regular, cylindrical, shape, although some exceptions have been observed in A. suum (Kessel et al, 1961), Metastrongylus sp. (Jenkins & Erasmus, 1969), Hexatylus viviparus (Shepherd & Clark, 1976) and Rhabditophanes sp.…”

“…Detailed information on the internal structure of H. gingivalis is lacking, i.e., whether the ultrastructural morphology resembles other known parasitic nematodes of mammals (e.g., Ascaris suum) or is more similar to that of other free-living bacteriovorous species (Borgonie et al, 1995). Various ultrastructural analyses of the intestine have been done on plant-parasitic (reviewed in Geraert, 1992;Endo et al, 1997), animalparasitic (Kessel et al, 1961;Wright, 1963;Jenkins & Erasmus, 1969;Smith & Harness, 1972;Wright et al, 1985;Endo & Nickle, 1991;Frantová & Moravec, 2004), marine (Deutsch, 1978;Van De Velde & Coomans, 1989;Miljutin & Tchesunov, 2001;Miljutin et al, 2006), predatory (Arpin & Kilbertus, 1981) and terrestrial bacteriovorous (Epstein et al, 1971;Borgonie et al, 1995) nematodes. The general structure of the intestine appears quite uniform, with the exception of some marine (e.g., Miljutin & Tchesunov, 2001;Miljutin et al, 2006) and plant-parasitic taxa (Geraert, 1992).…”