Kortbawi Hannah M, Marczak Ryan J, Rajan Jayant V, Bulaong Nash L, Pak John E, Wu Wesley, Wang Grace, Mitchell Anthea, Saxena Aditi, Maheshwari Aditi, Fleischmann Charles J, Kelly Emily A, Teal Evan, Townsend Rebecca L, Stramer Susan L, Okamoto Emi E, Sherbuk Jacqueline E, Clark Eva H, Gilman Robert H, Colanzi Rony, Gennatas Efstathios D, Bern Caryn, DeRisi Joseph L, Whitman Jeffrey D
Department of Biochemistry and Biophysics, University of California San Francisco; San Francisco, CA, USA.
Medical Scientist Training Program, University of California San Francisco; San Francisco, CA, USA.
medRxiv. 2025 Feb 21:2025.01.22.25320967. doi: 10.1101/2025.01.22.25320967.
Infection by , the agent of Chagas disease, can irreparably damage the cardiac and gastrointestinal systems during decades of parasite persistence and related inflammation in these tissues. Diagnosis of chronic disease requires confirmation by multiple serological assays due to the imperfect performance of existing clinical tests. Current serology tests utilize antigens discovered over three decades ago with small specimen sets predominantly from South America, and lower test performance has been observed in patients who acquired infection in Central America and Mexico. Here, we attempt to address this gap by evaluating antibody responses against the entire proteome with phage display immunoprecipitation sequencing comprised of 228,127 47-amino acid peptides. We utilized diverse specimen sets from Mexico, Central America and South America, as well as different stages of cardiac disease severity, from 185 cases and 143 controls. We identified over 1,300 antigenic peptides derived from 961 proteins between specimen sets. A total of 67 peptides were reactive in 70% of samples across all regions, and 3 peptide epitopes were enriched in ≥90% of seropositive samples. Of these three, only one antigen, belonging to the trans-sialidase family, has not previously been described as a diagnostic target. Orthogonal validation of this peptide demonstrated increased antibody reactivity for infections originating from Central America. Overall, this study provides proteome-wide identification of seroreactive peptides across a large cohort spanning multiple endemic areas and identified a novel trans-sialidase peptide antigen (TS-2.23) with significant potential for translation into diagnostic serological assays.
恰加斯病病原体克氏锥虫的感染，在数十年寄生虫持续存在以及这些组织中相关炎症期间，会对心脏和胃肠系统造成无法修复的损害。由于现有临床试验的表现欠佳，慢性病的诊断需要通过多种血清学检测来确认。目前的血清学检测使用的是三十多年前发现的抗原，样本集主要来自南美洲，在中美洲和墨西哥感染克氏锥虫的患者中观察到检测性能较低。在这里，我们试图通过噬菌体展示免疫沉淀测序评估针对整个克氏锥虫蛋白质组的抗体反应来填补这一空白，该测序由228,127个47氨基酸肽组成。我们使用了来自墨西哥、中美洲和南美洲的不同样本集，以及185例病例和143例对照的不同心脏病严重程度阶段。我们在样本集之间鉴定出了来自961种蛋白质的1300多种抗原性克氏锥虫肽。共有67种肽在所有区域70%的样本中具有反应性，3个肽表位在≥90%的血清阳性样本中富集。在这三种中，只有一种属于转唾液酸酶家族的抗原以前未被描述为诊断靶点。对该肽的正交验证表明，对于源自中美洲的感染，抗体反应性增加。总体而言，本研究在跨越多个流行地区的大型队列中提供了全蛋白质组范围的血清反应性克氏锥虫肽鉴定，并鉴定出一种具有显著转化为诊断血清学检测潜力的新型转唾液酸酶肽抗原（TS-2.23）。
