Gill Ryan M, Coleman Neil M, Hunt Joan S
Department of Pathology and Laboratory Medicine, University of Kansas Medical Center, Kansas City, KS 66160, USA.
J Reprod Immunol. 2007 Jun;74(1-2):1-6. doi: 10.1016/j.jri.2006.08.083. Epub 2006 Sep 27.
LIGHT (homologous to lymphotoxins, exhibits inducible expression, competes with herpes simplex virus glycoprotein D for HVEM, a receptor expressed by T lymphocytes) is an apoptosis-inducing member of the tumor necrosis factor family of ligands. Messenger RNAs encoding LIGHT and its receptors, lymphotoxin-beta receptor (LTbetaR), decoy receptor-3 (DcR3) and herpes virus entry mediator (HVEM), are present in first trimester and term placentas. Proteins have been localized to specific cells in term but not earlier gestation placentas. Here, we have studied LIGHT and its receptors in early (6-7 weeks) and early-to-middle (8-13 weeks) gestation using immunohistology. Notable cell-specific, gestation-related features were identified. LIGHT and two of its receptors, a membrane-bound receptor that mediates apoptosis (LTbetaR) and a soluble receptor that interferes with LIGHT signaling (DcR3), were present in syncytiotrophoblast and cytotrophoblast cells in all samples but were detected in placental stromal cells only at week 8 and thereafter. HVEM, a membrane-bound receptor that protects against apoptosis, was expressed only on syncytiotrophoblast. These observations suggest that the LIGHT system may regulate early to middle stages of placental development via cell-specific, temporally programmed expression of the ligand and its receptors, and may also assist in preserving placental immune privilege.
LIGHT（与淋巴毒素同源，具有诱导性表达，与单纯疱疹病毒糖蛋白D竞争T淋巴细胞表达的受体HVEM）是肿瘤坏死因子配体家族中一种诱导细胞凋亡的成员。编码LIGHT及其受体——淋巴毒素β受体（LTβR）、诱饵受体3（DcR3）和疱疹病毒进入介质（HVEM）的信使核糖核酸存在于孕早期和足月胎盘组织中。在足月胎盘而非妊娠早期胎盘中，这些蛋白质已被定位到特定细胞。在此，我们利用免疫组织学方法研究了妊娠早期（6 - 7周）和妊娠早期至中期（8 - 13周）的LIGHT及其受体。我们发现了显著的细胞特异性、与妊娠相关的特征。LIGHT及其两个受体，即介导细胞凋亡的膜结合受体（LTβR）和干扰LIGHT信号传导的可溶性受体（DcR3），在所有样本的合体滋养层细胞和细胞滋养层细胞中均有表达，但仅在第8周及之后才在胎盘基质细胞中检测到。HVEM是一种具有抗细胞凋亡作用的膜结合受体，仅在合体滋养层细胞上表达。这些观察结果表明，LIGHT系统可能通过配体及其受体的细胞特异性、时间程序性表达来调节胎盘发育的早期至中期阶段，并且可能有助于维持胎盘的免疫豁免权。
