Predicting naturally acquired humoral immunity against malaria

预测针对疟疾的自然获得性体液免疫

• 批准号: 9312978
• 负责人: PHILIP Louis FELGNER
• 金额: $ 7.25万
• 依托单位: UNIVERSITY OF CALIFORNIA-IRVINE
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-05-15 至 2018-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9312978
• 关键词: Acute; Address; Adolescence; Adult; Africa; African; Age; Antibodies; Antibody Response; Antigens; Area; Award; Biological Markers; Blood; Cell Separation; Cessation of life; Child; Childhood; Clinical; Clinical Research; Cohort Studies; Collaborations; Cross-Sectional Studies; Disease; Enrollment; Ensure; Epidemiologic Studies; Epidemiology; Erythrocytes; Ethnic group; Exposure to; Falciparum Malaria; Funding; Genetic Polymorphism; Genetic Transcription; Genomic Segment; Genotype; Human; Humoral Immunities; Immune; Immunity; Immunodominant Antigens; Individual; Infant; Infection; Institutes; Kinetics; Knowledge; Leukocytes; Life; Longitudinal Studies; Malaria; Malaria Vaccines; Mali; Maternal antibody; Monitor; National Institute of Allergy and Infectious Disease; Nature; Open Reading Frames; Parasites; Pattern; Plasma; Plasmids; Plasmodium falciparum; Predisposition; Printing; Protein Microchips; Proteins; Proteomics; Resistance; Resistance development; Risk; Sampling; Seasons; Serum; Specificity; Specimen; Staging; Subunit Vaccines; Symptoms; Testing; Time; Vaccine Antigen; acquired immunity; aged; base; burden of illness; cohort; cytokine; genome sequencing; genome-wide; improved; insight; microorganism; novel; novel vaccines; prospective; response; tool; transcriptome sequencing; transmission process; vaccine development

DESCRIPTION (provided by applicant): We developed an approach to construct and probe protein microarrays on a genome-wide scale to characterize host antibody responses against more than 25 medically important infectious microorganisms. The lab has made 35,000 plasmids, printed the encoded proteins on 25,000 microarrays and probed them with 12,000 human serum specimens. The individual proteins printed on these arrays capture antibodies present in the serum of infected individuals, the amount of captured antibody can be quantified using fluorescent secondary antibody and antibody profiles that result after infection determined. Here we propose to apply this approach toward understanding the basis of naturally-acquired humoral immunity (NAI) to clinical malaria, to identify antibody biomarkers associated with protection from P. falciparum infection, and to discover novel malaria vaccine antigen candidates. People living in areas of intense Plasmodium falciparum (Pf) transmission develop resistance to the symptoms of malaria after repeated exposures to Pf parasite infection through childhood and adolescence. Probing a protein microarray containing 2,320 Pf proteins with sera collected from Pf-exposed Malian children and adults indicated that long-lived antibody responses are only acquired after years of repeated Pf infections and protective antibodies were identified against 49 specific Pf antigens.(2) Here we aim to extend these preliminary findings with a more comprehensive immuno-epidemiological analysis in Mali. Four thousand plasma samples which have already been collected from three NIAID-supported studies in Mali will be probed and analyzed. The longitudinal nature of these studies allows for antibody profiling at strategic time points before, during and after Pf infection and thus permits a prospective analysis of the relationship between antibody profiles and protection from malaria. We will also investigate the P. falciparum-specific antibody profile of infants and children aged 3 months to 5 years as they transition from maternally-derived antibodies to naturally-acquired antibodies through P. falciparum exposure. Finally, in a cross-sectional analysis we will investigate the isotype profile and antigen specificity of Pf-specific antibodies in the Fulani and Dogon people in Mali, distinct ethnic groups which have well-documented differential susceptibility to malaria. This proposal also takes advantage of recent funding from the NIAID Genome Sequencing Center (in collaboration with the J. Craig Venter Institute) to perform genotyping of targeted genomic regions of 700 individuals in one of the cohort studies as well as genome-wide transcription profiling (by RNA-seq.) of the same individuals before, during and after P. falciparum infection. This will provide a unique opportunity to examine prospectively the relationship between genetic polymorphisms, leukocyte transcription profiles and P. falciparum-specific antibody responses.

描述（由申请人提供）：我们开发了一种在全基因组范围内构建和探测蛋白质微阵列的方法，以表征针对超过 25 种医学上重要的传染性微生物的宿主抗体反应。该实验室已经制造了 35,000 个质粒，将编码的蛋白质打印在 25,000 个微阵列上，并用 12,000 个人类血清样本对其进行了探测。打印在这些阵列上的单个蛋白质捕获感染个体血清中存在的抗体，捕获的抗体的量可以使用荧光二抗和感染确定后产生的抗体谱进行定量。在这里，我们建议应用这种方法来了解临床疟疾的自然获得性体液免疫（NAI）的基础，识别与预防恶性疟原虫感染相关的抗体生物标志物，并发现新型疟疾疫苗候选抗原。 生活在恶性疟原虫 (Pf) 传播严重地区的人们在童年和青少年时期反复接触 Pf 寄生虫感染后，会对疟疾症状产生抵抗力。用从暴露于 Pf 的马里儿童和成人收集的血清探测含有 2,320 个 Pf 蛋白的蛋白质微阵列表明，只有在多年重复 Pf 感染后才能获得长效抗体反应，并且针对 49 种特定 Pf 抗原鉴定出保护性抗体。(2) 在这里，我们的目标是通过在马里进行更全面的免疫流行病学分析来扩展这些初步发现。将从 NIAID 支持的马里三项研究中收集到的 4000 份血浆样本将被进行探测和分析。这些研究的纵向性质允许在 Pf 感染之前、期间和之后的战略时间点进行抗体谱分析，从而可以对抗体谱与疟疾预防之间的关系进行前瞻性分析。我们还将调查 3 个月至 5 岁婴儿和儿童的恶性疟原虫特异性抗体谱，因为他们通过接触恶性疟原虫从母源性抗体转变为自然获得性抗体。最后，在横断面分析中，我们将研究富拉尼人和多贡人中 Pf 特异性抗体的同种型谱和抗原特异性。 马里，不同的种族群体对疟疾的易感性存在差异。该提案还利用 NIAID 基因组测序中心（与 J. Craig Venter 研究所合作）最近提供的资金，对其中一项队列研究中的 700 名个体的目标基因组区域进行基因分型，并对同一个体在恶性疟原虫感染之前、期间和之后进行全基因组转录分析（通过 RNA 测序）。这将为前瞻性研究遗传多态性、白细胞转录谱和恶性疟原虫特异性抗体反应之间的关系提供一个独特的机会。