VTCN1 regulation of MHC in early human placental development

VTCN1 对人类早期胎盘发育中 MHC 的调节

• 批准号: 10092932
• 负责人: Toshihiko Ezashi
• 金额: $ 19.38万
• 依托单位: UNIVERSITY OF MISSOURI-COLUMBIA
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-01-31 至 2022-07-01
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10092932
• 关键词: Abbreviations; Abnormal placentation; Address; Affect; Aggressive behavior; Allogenic; Allografting; BMP4; Binding; Blood group antigen f; Cell Proliferation; Cell model; Cell surface; Cells; Cervix Neoplasms; Characteristics; Clinical; Complex; DNA Binding Domain; Decidua; Detection; Development; Disease; Dissection; Down-Regulation; Endometrial Neoplasms; Ensure; Environment; Ethics; Event; Fetal Development; Fetal Growth Retardation; Fetus; First Pregnancy Trimester; Genetic Transcription; HLA Antigens; Hepatitis B e Antigens; Histocompatibility Antigens; Histocompatibility Antigens Class II; Human; Human Chorionic Gonadotropin; Immune; Immunocompetent; Immunohistochemistry; Immunologics; Immunology; Implant; In Vitro; Invaded; Knowledge; Learning; Logistics; MAP Kinase Gene; MHC class II transactivator protein; Major Histocompatibility Complex; Malignant Neoplasms; Maternal-Fetal Exchange; Messenger RNA; Mitogen-Activated Protein Kinases; Modeling; Mothers; Normal tissue morphology; Nucleotides; Pathway interactions; Pattern; Physiological; Placenta; Placentation; Play; Post-Transcriptional Regulation; Pre-Eclampsia; Pregnancy; Pregnancy Rate; Pregnancy loss; Premature Birth; Process; Prognosis; Proteins; Regimen; Regulation; Regulatory Element; Reproductive Immunology; Research; Risk; Role; SET Domain; Sampling; Second Pregnancy Trimester; Small Interfering RNA; Surface; Syncytiotrophoblast; T-Cell Activation; T-Cell Receptor; TCR Activation; Testing; Tissues; Trans-Activators; Undifferentiated; VTCN1 gene; Vascularization; beta-2 Microglobulin; cancer cell; cytotrophoblast; early pregnancy; early pregnancy loss; embryonic stem cell; healthy pregnancy; human embryonic stem cell; human tissue; implantation; improved; in vitro Model; induced pluripotent stem cell; inhibitor/antagonist; innovation; knock-down; matrigel; member; neovascularization; novel; novel diagnostics; novel therapeutics; ovarian neoplasm; overexpression; pancreatic neoplasm; pathogen; pregnancy disorder; programmed cell death ligand 1; protein expression; receptor; response; selective expression; stem cell differentiation; stem cell model; stem cells; tool; trophoblast; tumor; tumor immunology; tumor-immune system interactions

Improper peri-implantation placental development may contribute to feto-maternal diseases (preterm birth, intrauterine growth retardation, preeclampsia) and high rates of pregnancy loss. Since these events occur prior to clinical detection of pregnancy, studies of very early human placental development are ethically and logistically constrained. The proposed project uses an innovative human embryonic stem cell (hESC)-derived model to study primitive trophoblast in vitro. The placenta resembles a cancer in that an implanting fetus and a developing cancer both involve host tissue invasion, massive cellular proliferation, neo-vascularization, and alterations in the immediate immune microenvironment. The placenta of the implanting fetus is one of the only non-cancerous tissues that displays physiologic downregulation of the classical major histocompatibility complex (MHC) class I (MHC-I) transplantation antigens, human leukocyte antigens (HLA)-A and -B. While positive regulatory elements for MHC class II regulation are described, little is known about such regulation of MHC class I expression in noncancerous tissues, including the placenta. Human embryonic stem cells (hESCs) have been used in a novel in vitro model of the stages of human placental development that occur prior to clinical detection of pregnancy. Several mRNAs and proteins that are selectively expressed at high levels in early pregnancy have been identified by using the model. Of those studied, all appear to play roles in invasion. Remarkably, siRNA silencing of one of these proteins, V-Set Domain Containing T Cell Activation Inhibitor 1 (VTCN1), in our model for early trophoblast strongly up-regulated the expression of the MHC class I human leukocyte antigens (HLA)-A and -B, which are normally not expressed in human trophoblast, slightly up-regulated the normally resident HLA-C, but had no effect on expression of the placenta-specific HLA-G. VTCN1 is recognized as a member of the B7 superfamily of cell-surface co-receptors that regulate T cell receptor interactions with MHC molecules. It has been postulated that VTCN1 neo-expression affects cancer cells’ ability to evade host immune detection. These results highlight the efficacy of our in vitro models for filling several important knowledge gaps. The unique ability to model peri-implantation placental development in vitro will enable dissection of the control of MHC-I expression on human trophoblast (TB), particularly testing the hypothesis that the lack of expression of HLA-A and -B by TB is controlled by VTCN1 through largely indirect mechanisms. There are three aims to the proposal: 1) Demonstrate classical MHC class I suppression by VTCN1 in various TB models, including hESC-derived primitive trophoblast, by using VTCN1 knock-down and overexpression; 2) Define the transcriptional pathways and transcriptional and immediate post-transcriptional regulation involved in VTCN1-related alterations in TB MHC-I expression and 3) Identify protein partners of VTCN1 in in vitro cell models of early TB to discover and confirm pathways involved in VTCN1 regulation of MHC class I expression. These studies will have application to the origins of common disorders of abnormal placentation and to the understanding of cancer immunology.

不适当的围着床期胎盘发育可能会导致胎儿-母体疾病（早产，宫内 生长迟缓、先兆子痫）和高流产率。由于这些事件发生在临床检测妊娠之前，因此对极早期人类胎盘发育的研究在伦理和后勤方面受到限制。该项目使用创新的人类胚胎干细胞（hESC）衍生模型在体外研究原始滋养层。胎盘类似于癌症，因为植入的胎儿和发展中的癌症都涉及宿主组织侵入、大量细胞增殖、新血管形成和直接免疫微环境的改变。植入胎儿的胎盘是显示经典的主要组织相容性复合体（MHC）I类（MHC-I）移植抗原、人白细胞抗原（HLA）-A和-B的生理性下调的仅有的非癌组织之一。虽然描述了MHC II类调节的正调节元件，但对包括胎盘在内的非癌组织中MHC I类表达的这种调节知之甚少。人类胚胎干细胞（hESC）已被用于一种新的体外模型的阶段，人类胎盘的发展，发生在临床检测怀孕。已经通过使用该模型鉴定了在早期妊娠中以高水平选择性表达的几种mRNA和蛋白质。在这些研究中，似乎都在入侵中发挥作用。值得注意的是，在我们的早期滋养层模型中，这些蛋白质之一，含V-Set结构域的T细胞活化抑制剂1（VTCN 1）的siRNA沉默强烈上调了MHC I类人白细胞抗原（HLA）-A和-B的表达，其通常不在人滋养层中表达，轻微上调了正常驻留的HLA-C，但对胎盘特异性HLA-G的表达没有影响。VTCN 1被认为是调节T细胞受体与MHC分子相互作用的细胞表面共受体B7超家族的成员。据推测，VTCN 1新表达影响癌细胞逃避宿主免疫检测的能力。这些结果突出了我们的体外模型在填补几个重要知识空白方面的功效。在体外模拟围植入期胎盘发育的独特能力将使得能够剖析人滋养层（TB）上MHC-I表达的控制，特别是测试TB缺乏HLA-A和-B表达是由VTCN 1通过主要间接机制控制的假设。该提案有三个目的：1）通过使用VTCN 1敲低和过表达，在各种TB模型（包括hESC衍生的原始滋养层细胞）中证明VTCN 1对经典的MHC I类抑制; 2）确定TB MHC-I中涉及VTCN 1相关改变的转录途径以及转录和转录后即刻调控 3）在早期TB的体外细胞模型中鉴定VTCN 1的蛋白伴侣，以发现和确认参与VTCN 1调节MHC I类表达的途径。这些研究将应用于异常胎盘的常见疾病的起源和癌症免疫学的理解。