Itatani C A
Department of Biological Sciences, California State University, Long Beach 90840.
J Parasitol. 1994 Aug;80(4):644-8.
The proposed life cycle of the opportunistic organism Pneumocystis carinii (PC) includes the formation of a thick-walled cyst containing haploid progeny. The progeny cells mature within the cyst and are somehow released, leaving a collapsed empty cyst behind. Pneumocystis carinii cysts containing 8 intracystic bodies (ICB) as well as empty collapsed cysts have been commonly observed. In this study a single pore in the cyst walls of PC was observed by transmission electron microscopy in infected rat-lung preparations. Presence of a single pore in the cyst wall of an empty but noncollapsed cyst and in collapsed, empty cysts suggests that pore formation may be a mode of excystation for ICB of P. carinii.
所提出的机会性生物体卡氏肺孢子虫（PC）的生命周期包括形成一个含有单倍体后代的厚壁囊肿。后代细胞在囊肿内成熟并以某种方式释放出来，留下一个塌陷的空囊肿。通常观察到含有8个囊内小体（ICB）的卡氏肺孢子虫囊肿以及塌陷的空囊肿。在本研究中，通过透射电子显微镜在感染大鼠肺标本中观察到PC囊肿壁上有一个单孔。在空的但未塌陷的囊肿以及塌陷的空囊肿的囊肿壁上存在单孔，这表明孔的形成可能是卡氏肺孢子虫ICB的脱囊方式。
