The steroid hormone, 1 alpha,25-dihydroxyvitamin D3 (calcitriol), has been shown to inhibit T cell proliferation, primarily through inhibition of interleukin 2 (IL-2) production. In these experiments, we show that calcitriol also markedly inhibited production of the lymphokine, gamma interferon (IFN-gamma), by activated human T lymphocytes. Regulation of both IL-2 and IFN-gamma production as well as transferrin receptor (TfR) expression by calcitriol was apparent at the messenger RNA (mRNA) level as determined by Northern blotting. The decrease in IL-2 and IFN-gamma mRNA that occurred with calcitriol treatment was coordinate and not apparent up to 12 h after phytohemagglutinin stimulation, whereas decreased accumulation of TfR mRNA was not present before 24-36 h. Furthermore, the effects of calcitriol on IL-2, IFN-gamma, and TfR mRNA accumulation were specific; actin mRNA accumulation was comparable between control and treated cells. These data indicate that calcitriol regulated proteins associated with T cell activation at the transcriptional level and that these effects were mediated in a specific, coordinate fashion.
W F Rigby, S Denome, M W Fanger
Usage data is cumulative from May 2020 through May 2021.
Usage information is collected from two different sources: this site (JCI) and Pubmed Central (PMC). JCI information (compiled daily) shows human readership based on methods we employ to screen out robotic usage. PMC information (aggregated monthly) is also similarly screened of robotic usage.
Various methods are used to distinguish robotic usage. For example, Google automatically scans articles to add to its search index and identifies itself as robotic; other services might not clearly identify themselves as robotic, or they are new or unknown as robotic. Because this activity can be misinterpreted as human readership, data may be re-processed periodically to reflect an improved understanding of robotic activity. Because of these factors, readers should consider usage information illustrative but subject to change.