新一期英國(guó)《自然－免疫學(xué)》雜志刊登報(bào)告說，維生素D不僅是身體生長(zhǎng)發(fā)育所必需的，在免疫方面也發(fā)揮著重要作用，它是免疫細(xì)胞T細(xì)胞對(duì)異物發(fā)動(dòng)攻擊的“司令員”。

        丹麥哥本哈根大學(xué)研究人員報(bào)告說，免疫系統(tǒng)中的T細(xì)胞具有識(shí)別并攻擊細(xì)菌和病毒等異物的功能，但它平時(shí)并不處于“戰(zhàn)斗狀態(tài)”，需要得到一個(gè)“攻擊信號(hào)”才能完成從不活躍狀態(tài)到活躍狀態(tài)的轉(zhuǎn)換。維生素D就在這個(gè)過程中扮演了“司令員”的角色。這次的研究發(fā)現(xiàn)，如果沒有維生素D，T細(xì)胞就算探測(cè)到異物也不會(huì)采取行動(dòng)，依然處于不活躍狀態(tài)。

        研究人員說，這一發(fā)現(xiàn)說明，可以通過調(diào)節(jié)體內(nèi)維生素D含量來控制免疫反應(yīng)。比如，免疫功能弱的人可以通過補(bǔ)充維生素D來增強(qiáng)抗病能力；而在進(jìn)行器官移植等手術(shù)后，則可以通過減少體內(nèi)維生素D含量，來減少排異反應(yīng)。

        維生素D存在于魚類、雞蛋等天然食物中，多曬太陽也有助于人體合成維生素D。維生素D通過調(diào)節(jié)體內(nèi)鈣、磷等元素的代謝來維持骨骼、牙齒的正常生長(zhǎng)發(fā)育。

勁馬生物推薦原始出處：

Nature Immunology 7 March 2010 | doi:10.1038/ni.1851

Vitamin D controls T cell antigen receptor signaling and activation of human T cells

Marina Rode von Essen1, Martin Kongsbak1, Peter Schjerling2,4, Klaus Olgaard5, Niels ?dum1,3 & Carsten Geisler1

Phospholipase C （PLC） isozymes are key signaling proteins downstream of many extracellular stimuli. Here we show that naive human T cells had very low expression of PLC-γ1 and that this correlated with low T cell antigen receptor （TCR） responsiveness in naive T cells. However, TCR triggering led to an upregulation of ~75-fold in PLC-γ1 expression, which correlated with greater TCR responsiveness. Induction of PLC-γ1 was dependent on vitamin D and expression of the vitamin D receptor （VDR）. Naive T cells did not express VDR, but VDR expression was induced by TCR signaling via the alternative mitogen-activated protein kinase p38 pathway. Thus, initial TCR signaling via p38 leads to successive induction of VDR and PLC-γ1, which are required for subsequent classical TCR signaling and T cell activation.

1 Department of International Health, Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark.
2 Center for Healthy Aging, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark.
3 Department of Biology, Faculty of Science, University of Copenhagen, Copenhagen, Denmark.
4 Institute of Sports Medicine, Bispebjerg Hospital, Rigshospitalet and Faculty of Health Sciences, University of Copenhagen, Denmark.
5 Department of Nephrology, Rigshospitalet and Faculty of Health Sciences, University of Copenhagen, Denmark.