Jill M. Siegfried

Monolayer culture of human endometrium: Methods of culture and identification of cell types

SummaryMonolayer cultures can be established from human endometrial tissue after enzymatic dispersal into isolated glands or single cells. Three cell types that have distinct morphology by light and electron microscopy are observed in the resulting primary cultures. One cell type, an elongated spindle cell, is similar in appearance to fibroblasts derived from other tissues. A second cell type forms colonies of tightly cohesive cells, ranging in shape from oval to polygonal. These cells have typical organelles and junctional complexes characteristic of epithelial cells from the endometrium. The third cell type assumes a pavement-like appearance composed of polygonal cells when viewed by phase contrast microscopy, but lacks distinctive ultrastructural features of epithelial cells. These cells in culture resemble the endometrial stromal cell, the predominant cell type of the human endometrium in vivo. The epithelial cell does not survive subculturing but the other two cell types can be passaged through several generations and can be stored in liquid nitrogen and subsequently returned to culture.

Histochemical identification of cultured cells from human endometrium.

SummaryHistochemical techniques have been applied to the identification of cell types cultured from human endometrium. Previous work from this laboratory characterized two principtal cell types found in cultures of endometrium: a mature epithelial cell and another cell which was classified as the endometrial stromal cell based on light and electron microscopy. In this report we compare the histochemical staining of endometrial tissue in frozen sections to that of cultured cells. These results confirm the epithelial and stromal nature of the respective cell types. Several markers were found that could distinguish between cells of epithelial and stromal origin. The enzymes alkaline phosphatase, γ-glutamyltranspeptidase, peroxidase, and β-glucuronidase were localized in glandular and surface epithelia in frozen sections and in colonies of epithelial cells in culture. Stroma in frozen sections and cultured stromal cells contained leucine aminopeptidase and fibronectin. Epithelial sections and in culture could also be distinguished from cells of stromal origin by preferential binding of lotus and peanut lectin. Several other markers were found in both endometrial epithelium and stroma.

Morphology and growth potential of stromal cell cultures derived from human endometrium

SummaryPropagable cell cultures derived from human endometrial tissue were determined to contain cells predominantly of stromal cell origin based on their morphologic resemblance to endometrial stromal cells. These features included nexi, solitary cilia, and predecidual cytology. In addition to morphology the cell cultures retained a normal karyotype and responded to steroid hormones as evidenced by cellular aggregation. The stromal cells were evaluated for a variety of characteristics associated with transformed cells and seemed to be biologically normal without neoplastic phenotypes. Growth potential of the stromal cell cultures was also characterized in normal maintenance medium, in nutritionally depleted medium with reduced levels of calcium or serum, and in medium with increased levels of serum. The prolonged survival of the stromal cells in vitro coupled with the retention of in vivo characteristics and an absence of neoplastic phenotype provides a human cell system that is amenable to a variety of long-term experimental analyses.

Characterization of a pure heterologous sarcoma of the uterus: Rhabdomyosarcoma of the corpus

A case of a pure heterologous sarcoma of the uterine corpus composed exclusively of rhabdomyosarcomatous elements has been studied by multiple morphologic and biochemical techniques. The neoplasm filled the endometrial cavity and protruded out the cervical os, but the myometrium was only superficially invaded. The tumor did not extend outside the corpus. The pathologic features are discussed in detail. Evidence of striated muscle differentiation could be identified on light microscopic and ultrastructural examination. Immunoperoxidase staining of tumor cells with antibodies to myoglobin were positive. Histochemical preparations for lactate dehydrogenase, succinic dehydrogenase, and acid phosphatase were also positive in neoplastic cells. Other stains gave equivocal or negative results. These findings are discussed in comparison with previous reports.