1 China Medical University Affiliated Shengjing Hospital Research Center and Key Laboratory of Congenital Malformation Research, Ministry of Health, No. 36, Sanhao Street, Heping District, Shenyang City, Liaoning Province, China, 110004
2 China Medical University Affiliated Shengjing Hospital Research Center and Key Laboratory of Congenital Malformation Research, Ministry of Health, Shenyang City, Liaoning Province, China
Background: Secretory component (SC) is the extracellular component of the polymeric immunoglobulin receptor (pIgR) that functions as a receptor for externally secreted polymeric immunoglobulins such as secretory IgA. SC expression is regulated by a signaling pathway involving TNF-a.
Methods: Caco-2 cells were cotreated with TNF-a plus either Wortmannin, which inhibits PI3K, or Rapamycin, which inhibits mTOR. The expression of SC and pIgR mRNA were assessed by immunocytochemistry, Western blotting, and Quantitative real-time PCR.
Results: Wortmannin and Rapamycin decreased the fraction of cells expressing SC, as well as the total expression of SC protein and pIgR mRNA.
Conclusions: TNF-a regulation of SC expression is mediated through a PI3K/AKT/mTOR signaling pathway in Caco-2 cells.
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