US EPA

3095097 

Journal Article 

Human amniotic epithelial cells are morphologically homogeneous: enzymehistochemical, tracer, and freeze-substitution fixation study 

Iwasaki, R; Matsubara, S; Takizawa, T; Takayama, T; Yashiro, T; Suzuki, M 

2003 

Yes 

European Journal of Histochemistry
ISSN: 1121-760X
EISSN: 2038-8306 

47 

3 

223-231 

English 

14514413 

10.4081/831 

WOS:000185121200006 

We examined the fine subcellular morphology of human amniotic epithelial cells and attempted to answer the question as to whether amniotic epithelial cells consist of heterogeneous or homogeneous cells, which has long been controversial. Study subjects were fetal membranes from pregnant women (n=18) who abdominally gave birth to healthy infants at term (37.9+/-0.7 weeks of gestation, mean+/-sd). The methods employed were transmission electron microscopy, enzymehistochemistry, tracer permeability analysis, and freeze-substitution fixation. The labelings for acid phosphatase, cytochrome c oxidase, and CA++ATPase were seen in the lysosomes, mitochondria, and lateral plasma membranes, respectively. The staining distribution pattern of these three enzymes and the morphology of the organelle highlighted by these enzymehistochemistry did not differ among cells. Freeze-substitution fixation revealed that intercellular spaces in the amniotic epithelial cells were narrower than previously thought, but the tracers (horse radish peroxidase and lanthanum nitrate) fully entered these spaces. There were no variations in the tracer permeability among cells. All cells from freeze-substitution fixation exhibited the same morphological features. From these morphological viewpoints, we conclude that human term amniotic epithelial cells consist of a homogeneous cell population. 

amniotic epithelium; cytochrome c oxidase; enzyme histochemistry; tracer; freeze-substitution fixation