Scanning and Transmission Electron Microscopy of the Oocyst Wall of Isospora lacazei

Authors

Clarence A. Speer, University of Montana - Missoula
Alan A. Marchiondo, University of Texas Medical Branch
Bodo Mueller, University of Bielefeld
Donald W. Duszynski, University of New Mexico - Main Campus

Date of this Version

1979

Comments

Published in ZEITSCHRIFT FUR PARASITENKUNDE 59:3 (1979), pp. 219-225. Copyright © 1979 Springer-Verlag.

Abstract

The oocyst wall of Isospora lacazei from sparrows was studied with scanning (SEM) and transmission (TEM) electron microscopy. In TEM, t he oocyst wall consisted of four distinct layers (Ll-4). The innermost layer, Ll, was moderately electron-lucent and 240-285 nm thick; L2 was electronJense and 210-240 nm thick; L3 was moderately electron-lucent and 15-150 nm thick; L4, the outer most layer, was discontinuous and consisted of electron-dense discoid bodies which measured 180-220 nm x 320-840 nm. The discoid bodies of L4 as seen by TEM appeared spheroid in shape when observed by SEM. One or two membranes were situated on or between various layers of the oocyst wall. One such membrane occurred on the inner margin of Ll, two closely applied membranes were interposed between LI and L2, one membrane occurred between L2 and L3, and one membrane on the outer margin of L3.