BIOCHEMICAL RELATIONSHIP OF PLATELET AND PLASMA HLA

人类白细胞抗原是决定人类免疫缺陷最重要的抗原系统。 异基因免疫患者输注的血小板存活情况。 为这些患者寻找相容的血小板是一个主要障碍 在血小板输注治疗中。这样做的主要目标是 提案的目的是开发新的方法来克服 随机献血者输血的免疫学耐受性 血小板。对于一种方法，我们将建立一个准确的 定量测定每一种特定物质的浓度 血小板上的人类白细胞抗原。一开始，单抗(摩押) 人类白细胞抗原分子的单态表位将被开发用于 用人工合成的多肽免疫小鼠的方法 含有保守的氨基酸序列。精准的 将通过以下方式实现对血小板上每种特定人类白细胞抗原的定量 用已建立的酶测量血小板上的总人类白细胞抗原- 联用免疫测定法和通过测定每种药物的相对含量 应用IEF-PAGE、抗-HLAMoAbs和抗HLAMoAbs检测血小板表面的特异性HLAs 免疫印迹。然后，可以使用结果来计算准确的 每种特定的人类白细胞抗原的浓度。这项化验将使我们能够 研究输注同种异体免疫病人的潜在益处 来自一两个低表达的捐献者的血小板 不匹配的人类白细胞抗原。它还可以用来比较 血小板膜表面特异性人类白细胞抗原的差异表达 淋巴细胞，以研究遗传调控的数量 每种特定的人类白细胞抗原在细胞上的表达，并探讨其在 特异性人类白细胞抗原的可变表达与疾病的关联 易感性和免疫反应性。 另一种方法是，我们将启动实验研究 8-甲氧补骨脂素和UV-A预处理血小板的应用 照射灭活受污染的白细胞 预防I类MHC的初级同种异体致敏作用 小鼠体内的抗原。小鼠被选中是因为它们具有良好的H- 2系统和具有良好定义的近交系的可用性 H-2单倍型。这项拟议研究的结果不仅将 为我们未来的临床试验提供重要信息 还将建立一个实验系统，可以用来 MHC体液免疫应答机制的研究 抗原是由供体白细胞触发的。这方面的进一步研究 方向将有助于更好地理解 组织和器官移植的免疫生物学。

HLA is the most important antigenic system in determining the survival of transfused platelets in alloimmunized patients. Finding compatible platelets for those patients is a major obstacle in platelet transfusion therapy. The primary objective of this proposal is to develop new approaches for overcoming the immunological refractoriness to transfusion of random donor platelets. For one approach, we will establish a precise quantitative assay to measure the concentration of each specific HLA on platelets. At the beginning, monoclonal antibodies (MoAb) against monomorphic epitopes of HLA molecules will be developed for this assay by immunizing mice with synthetic peptides containing conserved amino-acid sequences. The precise quantitation of each specific HLA on platelets will be achieved by measuring the total HLA on a platelet with an established enzyme- linked immunoassay and by determining the relative quantity of each specific HLA on platelets using IEF-PAGE, anti-HLA MoAbs and immunoblots. The results can then be used to calculate the exact concentration of each specific HLA. This assay will enable us to study the potential benefit of transfusing alloimmunized patients with platelets from donors who have a low expression of one or two mismatched HLA antigens. It can also be used to compare the variable expression of specific HLA between platelets and lymphocytes, to study the genetic regulation of quantitative expression of each specific HLA on cells, and to investigate the linkage of variable expression of specific HLA to disease susceptibility and immune responsiveness. For another approach, we will initiate experimental studies on the use of platelets pretreated with 8-methoxypsoralen and UV-A irradiation to inactivate contaminating leukocytes for the prevention of primary allosensitization against class I MHC antigens in mice. Mice are chosen for their well characterized H- 2 system and the availability of inbred strains with well defined H-2 haplotypes. The results of this proposed study not only will provide us with important information for a future clinical trial but also will establish an experimental system that can be used to study the mechanisms by which the humoral immune response to MHC antigen is triggered by donor leukocytes. Further research in this direction will contribute to a greater understanding of the immunobiology of tissue and organ transplantation.