Open AccessIdentification of Label‐Retaining Cells in Mouse Endometrium
Author(s) -
Chan Rachel W.S.,
Gargett Caroline E.
Publication year - 2006
Publication title -
stem cells
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.159
H-Index - 229
eISSN - 1549-4918
pISSN - 1066-5099
DOI - 10.1634/stemcells.2005-0411
Subject(s) - stromal cell , biology , endometrium , stem cell , progenitor cell , paracrine signalling , epithelium , bromodeoxyuridine , endocrinology , microbiology and biotechnology , medicine , andrology , immunology , cancer research , immunohistochemistry , receptor , biochemistry , genetics
Human and mouse endometrium (lining of the uterus) undergo cycles of growth and regression as part of each reproductive cycle. A well‐known method to identify somatic stem/progenitor cells and their location in the stem cell niche is the label‐retaining cell (LRC) approach. We hypothesized that mouse endometrium contains small populations of both epithelial and stromal somatic stem/progenitor cells that may be detected by the LRC technique. The overall objective of this study was to identify and quantify LRCs in mouse endometrium, to determine their location, and to identify their niche in this highly regenerative tissue. Endometrium was labeled for 3 days with bromodeoxyuridine (BrdU) in postnatal day 3 (P3) mice prior to gland development and prepubertal (P19) mice after glands had formed, followed by chase periods of up to 12 weeks. After an 8‐week chase, 3% of epithelial nuclei immunostained with BrdU antibody and were considered epithelial LRCs. These were primarily located in the luminal epithelium. Epithelial LRCs did not express estrogen receptor‐α (ER‐α). Stromal LRCs (6%) were found adjacent to luminal epithelium, at the endometrial‐myometrial junction, and near blood vessels after a 12‐week chase. Stromal LRCs were stem cell antigen‐1, CD45 − , and some (16%) expressed ER‐α, indicating their capacity to respond to estrogen and transmit paracrine signals to epithelial cells for endometrial epithelium regeneration. Both epithelial LRCs and some stromal LRCs, mainly located at the endometrial‐myometrial junction, were recruited into the cell cycle after estrogen‐stimulated endometrial regeneration, indicating a functional response to proliferative signals. This study has demonstrated for the first time the presence of both epithelial and stromal LRCs in mouse endometrium, suggesting that these stem‐like cells may be responsible for endometrial regeneration.