Prevalence and immunogenicity of HNA-3a and -3b antibodies and antigens

HNA-3a 和 -3b 抗体和抗原的流行率和免疫原性

• 批准号: 8031461
• 负责人: Richard Herbert Aster
• 金额: $ 24.98万
• 依托单位: VERSITI WISCONSIN, INC.
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-01-01 至 2012-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8031461
• 关键词: Acute Lung Injury; Address; Alleles; Alloantigen; Amino Acid Substitution; Antibodies; Antigens; Biological Assay; Biological Response Modifiers; Blood; Blood Transfusion; Blood donor; Blood donor screening; Cells; Complication; Detection; Donor Selection; Exposure to; FDA approved; Female; Genetic Polymorphism; Grant; HLA Antigens; Immunoassay; Incidence; Individual; Insecta; Isoantibodies; Laboratories; Length; Leukocytes; Membrane; Molecular; Mutate; Patients; Peptides; Phase; Phenotype; Population; Pregnancy; Prevalence; Property; Proteins; Reaction; Recombinants; Research; Research Personnel; Safety; Sampling; Serological; Serum; Solid; System; Testing; Time; Transfusion; Work; base; blood product; choline transporter; extracellular; immunogenicity; improved; male; mortality; neutrophil; prototype; theories

DESCRIPTION (provided by applicant): Transfusion-associated acute lung injury (TRALI), currently the leading cause of transfusion- associated fatality, is triggered by transfusion of blood products containing leukocyte antibodies and/or biological response modifiers to susceptible patients. Although many different leukocyte antibodies have been shown to induce TRALI, those specific for the leukocyte antigen HNA-3a are especially prone to cause very severe, and often fatal reactions. Unfortunately, it has not been possible to screen blood donors routinely for anti-HNA-3a because its molecular properties have for many years eluded investigators and because HNA-3a was thought to be neutrophil-specific, a cell difficult to use in serologic studies. Thus, very little is known about the prevalence of anti-HNA-3a in blood donors and the immunogenicity of this antigen is poorly understood. Even less is known about antibodies that recognize HNA-3b, the allele of HNA-3a, although they should, in theory, be as likely to cause TRALI as anti-HNA-3a. We recently showed that HNA-3a is carried on choline transporter- like protein 2 (CTL2) and that the HNA-3a/b polymorphism is almost certainly determined by an R>Q154 (R=HNA-3a, Q = HNA-3b) amino acid substitution in the first extracellular loop of the 10- membrane-spanning CTL2 protein. These findings suggest ways to develop a practical assay for detection of anti-HNA-3a and anti-3b suitable for routine donor screening. In this application, we propose to generate recombinant and synthetic CTL2 and CTL2 fragments containing R154 and Q154 and characterize their reactions against a panel of HNA-3-specific antibodies. Constructs found to be most sensitive and specific for anti-CTL2 detection will be produced in quantity, formatted into a prototype solid phase immunoassay, and used to screen 7,000 serum samples from transfused, non-transfused and parous males and females to determine the prevalence of anti-HNA-3a in these populations. The Q154 version of these constructs should provide comparable information about anti-HNA-3b. Findings made are expected to 1) define, for the first time, the prevalence of anti-HNA-3a and anti- HNA-3b in blood donor populations; 2) characterize the immunogenicity of HNA-3 and HNA-3b (likelihood of an antibody being induced upon exposure to antigen through transfusion or during pregnancy) and 3) establish a basis for determining whether routine screening of blood donors for anti-HNA-3a and anti-HNA-3b is warranted. PUBLIC HEALTH RELEVANCE: Transfusion-associated acute lung injury (TRALI) is a serious complication of blood transfusion and the most common cause of transfusion-related mortality. Transfusion of antibodies specific for white blood cells (leukocytes) is a major cause of TRALI. Antibodies against a leukocyte antigen designated HNA-3a are especially prone to cause severe, often fatal TRALI but, for technical reasons, it has not been possible to test blood donors to detect them. Recent findings made in our laboratory make it likely that this obstacle can be overcome and studies to accomplish this are described in this application.))

描述（由申请人提供）：输血相关急性肺损伤（TRALI）是目前输血相关死亡的主要原因，是由向易感患者输注含有白细胞抗体和/或生物反应调节剂的血液制品引发的。尽管许多不同的白细胞抗体已被证明可诱导 TRALI，但那些对白细胞抗原 HNA-3a 具有特异性的抗体特别容易引起非常严重且常常致命的反应。不幸的是，不可能对献血者进行常规抗 HNA-3a 筛查，因为多年来研究人员一直未能了解其分子特性，而且 HNA-3a 被认为是中性粒细胞特异性的，而这种细胞很难用于血清学研究。因此，对于献血者中抗 HNA-3a 的流行情况知之甚少，并且对该抗原的免疫原性知之甚少。关于识别 HNA-3b（HNA-3a 的等位基因）的抗体知之甚少，尽管理论上它们应该与抗 HNA-3a 一样可能引起 TRALI。我们最近表明，HNA-3a 由胆碱转运蛋白样蛋白 2 (CTL2) 携带，并且 HNA-3a/b 多态性几乎肯定是由 10 跨膜 CTL2 蛋白的第一个细胞外环中的 R>Q154 (R=HNA-3a，Q = HNA-3b) 氨基酸取代决定的。这些发现提出了开发一种实用检测方法来检测适合常规供体筛选的抗 HNA-3a 和抗 3b 的方法。在此应用中，我们建议生成包含 R154 和 Q154 的重组和合成 CTL2 和 CTL2 片段，并表征它们对一组 HNA-3 特异性抗体的反应。被发现对抗 CTL2 检测最敏感和特异的构建体将被大量生产，形成原型固相免疫测定，并用于筛选来自输血、非输血和经产男性和女性的 7,000 份血清样本，以确定这些人群中抗 HNA-3a 的流行率。这些构建体的 Q154 版本应提供有关抗 HNA-3b 的可比信息。研究结果预计将 1) 首次确定献血者群体中抗 HNA-3a 和抗 HNA-3b 的患病率； 2) 表征 HNA-3 和 HNA-3b 的免疫原性（通过输血或怀孕期间接触抗原后诱导抗体的可能性），3) 为确定是否有必要对献血者进行抗 HNA-3a 和抗 HNA-3b 常规筛查奠定基础。 公共卫生相关性：输血相关性急性肺损伤 (TRALI) 是输血的严重并发症，也是输血相关死亡的最常见原因。输入针对白细胞（白细胞）的特异性抗体是 TRALI 的主要原因。针对称为 HNA-3a 的白细胞抗原的抗体特别容易引起严重且往往致命的 TRALI，但由于技术原因，无法通过测试献血者来检测它们。我们实验室的最新发现使得这一障碍有可能被克服，并且本申请中描述了实现这一目标的研究。））