Sarcocystis sp.

Gondim, Luís F. P., Soares, Rodrigo M., Tavares, Aline S., Borges-Silva, Waléria, de Jesus, Rogério F., Llano, Horwald A. B. & Gondim, Leane Q., 2019, Sarcocystis falcatula-like derived from opossum in Northeastern Brazil: In vitro propagation in avian cells, molecular characterization and bioassay in birds, International Journal for Parasitology: Parasites and Wildlife 10, pp. 132-137 : 134

3.1. Sporocysts and direct isolation of Sarcocystis sp. in cell culture

Opossum's sporocysts which had been stored in antibiotic/antimycotic solution for 30 days, were used for direct isolation of the parasite in cell culture. Sporocysts were 11.07–12.0 μm x 7.51–8.59 μm (n = 23) in size. Sporozoites were visualized inside most sporocysts and autofluorescence of the sporocyst wall was observed after excitation with ultraviolet ( Fig. 1 ). Sporozoites were released from sporocysts using mechanical lysis by vortexing with glass beads and developed into schizonts/merozoites in Vero cells between six and eight days after inoculation of parasites' sporozoites on cell monolayers. Due to the slow growth and low number of parasites, the flasks were maintained without replication to new flasks for at least 40 days. Parasite schizonts in different degrees of maturation were visualized in the host cells. New monolayers of Vero cells were prepared and scraped cells from the original flasks were used for inoculations into these uninfected cells. The newly isolated strain is referred here and throughout the manuscript as Sarco-BA1. Aliquots of Sarco-BA1 containing merozoites and schizonts of the parasite inside DF-1 cells were frozen in liquid nitrogen.

Figures

Fig. 1. Sporocyst of Sarcocystis falcatula-like. Four sporozoites are visualized inside the sporocyst by light microscopy (A). Autofluorescence of the sporocyst wall is observed after excitation with ultraviolet on a fluorescence microscope (B).