| Estrogen response has been extensively studied in the ovariectomized immature ratmodel. It has been shown that one such ovarian hormone, 17β-estradiol (E2), induces biphasic uterine growth where early tissue expansion is characterized by a potent inflammatory-like response. This inflammatory response is of interest because it is brought about without a classic pathogenic trigger commonly associated with inflammation. In this study, a novel methodological approach to studying tissue specific inflammatory responses was developed using laser capture microdissection (LCM). LCM allows for the excision of specific cellular components from their complex organ environment by using a microscope containing a UV laser. Using LCM, sections of stromal and luminal epithelial tissue were generated from uterine cross-sections over nine time points (0h to 48h post- E2 treatment). Expression profiling was then performed on four target genes: Complement C3 (C3), Interleukin 1-beta (IL-1b), Monocyte Chemotactic Protein 1 (MCP-1), and Tumor Necrosis Factor-alpha (TNF-α). We found that all four target genes were upregulated in both luminal epithelial and stromal cells in response to estrogen administration. In the luminal epithelium, C3 levels peaked at 1h post-treatment with an 8-fold increase, IL-1b peaked at 4h post-treatment with a 6-fold increase, MCP-1 peaked at 1h post-treatment with a 8-fold increase, and TNF-α peaked at 4h post-treatment with an 8-fold increase. In the stroma, C3 levels peaked at 15 min post-treatment with an 8-fold increase, IL-1b peaked at 15 min post-treatment with a 7-fold increase, MCP-1 peaked at 1h post-treatment with a 7-fold increase, and TNF-α at 2h post-treatment with an 10-fold increase. Overall, in the majority of genes assayed, it appeared that stromal cells reacted earlier and more robustly to estrogen administration than the luminal epithelial cells. These results warrant further investigation into the tissue specific effects that estrogen may be having within the uterus. |
