Toxoplasma gondii: Bridging Morphology and Pathogenesis in a Protozoan Parasite

Abstract

These blood and tissue-dwelling protozoa can cause toxoplasmosis in both humans and animals. Toxoplasma gondii lives intracellularly within the cells of the reticuloendothelial system and parenchymal cells of both humans and mammalian animals, especially cats and birds.1 A study by Hartono found that approximately 40% of 50 swine samples contained Toxoplasma cysts.² Toxoplasma cysts are commonly found in the muscle and internal organs of these animals. Based on their habitat, T. gondii has two forms: intracellular and extracellular. Intracellularly, the parasite has a round or oval shape, making it difficult to distinguish from Leishmania species. Extracellularly, the parasite is crescent-shaped and slender, with one pointed end and the other blunt. Toxoplasma gondii is approximately 2-5 μm in size and has a nucleus located at the blunt end of the parasite.³ In the epithelial cells of the small intestine of cats, both asexual (schizogony) and sexual (gametogony, sporogony) cycles occur, producing oocysts that are excreted with feces. ...