Rhinosporidium seeberi. An ultrastructural study of its endosporulation phase and trophocyte phase.

The endosporulation phase of Rhinosporidium seeberi is the part of the life cycle most vulnerable to drug therapy. The laminated body formed from the precleavage sporangium has double-membraned tubular and vesicular structures within concentric layers. Similar tubular structures are also found in the developing sporoblast. The development of trophocytes involves three distinct phases. The early trophocyte retains many of the characteristics of the sporoblast as well as endoplasmic reticulum and other radiating filamentous structures in the cell wall. The itermediate tropocyte is larger (20 mug to 30mug m) and contains lipid bodies and microbodies, whereas the mature trophocyte is smaller (7mug m to9mug m) and microbodies are sparse or absent.