不同转染方式对人脐带血来源未成熟树突状细胞成熟特性的影响

发布时间：2018-06-23 00:06

本文选题：人脐带血 + 树突状细胞　；参考：《第三军医大学》2006年硕士论文

【摘要】： 树突状细胞(dendritic cell, DC)是一类重要的专职抗原呈递细胞(antigen-presenting cell , APC),虽然在体内的数量较少,但是其强大的抗原递呈和处理功能在机体的免疫反应中起重要的作用。DC的发育分化过程伴随着DC由不成熟的前体细胞向成熟细胞转变,未成熟DC(immature dendritic cell, imDC)与成熟DC(mature dendritic cell, mDC)在表型特征以及生物学功能上都有区别,而imDC最大的特点就是在体外可以诱导T淋巴细胞特异性低应答。临床上同种异体皮肤移植是目前大面积深度烧伤患者早期创面覆盖最直接、有效的治疗方法,但是由于皮肤的强烈抗原特性,导致移植后平均3周左右外源皮肤就会发生不可逆的排斥反应,极大抑制了自体微粒皮混合大张异体皮移植效果。免疫抑制药物虽可减轻免疫排斥,但是由于大面积严重烧伤患者的免疫功能耗竭,可导致严重感染威胁患者生命。若能有效利用imDC的特殊作用,移植前后在受者体内输入基因工程制备的imDC,可特异性地减轻皮肤移植后受者对供者抗原的免疫排斥反应、延长异体皮的存活时间,从而提高大面积深度烧伤患者的手术治疗效果。随着基因治疗的不断深入和发展,利用各种基因工程改造DC诱导器官移植耐受的实验性研究已经逐渐深入,如将各种趋化因子受体(chemokine receptor, CCR)的基因导入imDC中,使其靶向归巢至引流淋巴结中,有效发挥诱导耐受的功能,或者将针对细胞毒性T淋巴细胞相关抗原免疫球蛋白(CTLA-4Ig)的基因导入imDC中,表达的产物抑制imDC和T细胞表面CTLA-4的结合从而抑制共刺激效应和免疫激活,等等。因此,有效地实现imDC的免疫耐受功能需要将目的基因通过特定的方式整合到树突状细胞中,但在转染过程中,存在的一个问题是不同的转染方式常能影响DC作为抗原递呈细胞的功能,转染未成熟树突状细胞后可能会诱导其成熟。在本研究中,我们联合应用rhGM-CSF和rhIL-4体外诱导、扩增人脐带血分离的单核细胞,第7d收获细胞,从形态学、细胞表面标志物以及混合淋巴细胞反应(MLR)中对同种异体未致敏T淋巴细胞刺激能力三个方面进行鉴定。然后我们用两种常用的
[Abstract]:Dendritic cell (dendritic cell, DC) is an important class of specialized antigen presenting cells (antigen-presenting cell, APC), although the number in vivo is relatively small. However, its powerful antigen presentation and processing function plays an important role in the immune response of the body. The development and differentiation of DC is accompanied by the transformation of DC from immature precursor cells to mature cells. The phenotypic characteristics and biological functions of immature DC (immature dendritic cell, MDC and mature DC (mature dendritic cell, mDC) are different, and the biggest characteristic of imDC is that it can induce T lymphocyte specific low response in vitro. Skin allograft transplantation is currently the most direct and effective treatment for the early wound coverage in patients with extensive deep burns, but due to the strong antigenic characteristics of the skin, This resulted in irreversible rejection of the skin after transplantation for an average of 3 weeks, which greatly inhibited the effect of autologous skin grafts mixed with large skin allografts. Immunosuppressive drugs can reduce the immune rejection, but due to the exhaustion of immune function in patients with severe burn, it can lead to serious infection and threaten the lives of patients. If the special function of imDC can be effectively utilized, imDCs prepared by gene engineering before and after transplantation can specifically alleviate the immune rejection of donor antigen and prolong the survival time of allogeneic skin after skin transplantation. So as to improve the surgical treatment of large area deep burn patients. With the development of gene therapy, the experimental research on the induction of organ transplantation tolerance by using various genetic engineering has been gradually deepened, such as the introduction of various chemokine receptor (chemokine receptor,) genes into imDC. By targeting homing to the draining lymph nodes, it can effectively induce tolerance, or transfer the CTLA-4Ig gene into IMDC, which is related to the cytotoxic T lymphocyte antigen (CTLA-4Ig). The expressed product inhibits the binding of imDC to CTLA-4 on T cell surface, which inhibits costimulatory effect and immune activation, and so on. Therefore, it is necessary to integrate the target gene into dendritic cells in a specific way to achieve the immune tolerance function of imDC, but in the process of transfection, One problem is that different transfection methods can often affect the function of DC as antigen presenting cells, and immature dendritic cells may be induced to mature after transfection. In this study, we combined rhGM-CSF and rhIL-4 to amplify monocytes isolated from human umbilical cord blood in vitro. Cell surface markers and the stimulating ability of allogeneic unsensitized T lymphocytes were identified in mixed lymphocyte reaction (MLR). And then we use two commonly used
【学位授予单位】：第三军医大学
【学位级别】：硕士
【学位授予年份】：2006
【分类号】：R392

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