Câmara Raquel S B, Silva Ana L, Freitas Camila S, Lage Daniela P, Galvani Nathália C, Chaves Ana T, Assis Bárbara P N, Pimenta Breno L, Falcão Karolina O M, Dias Saulo S G, Rodrigues Maíza M, Tavares Grasiele S V, Galdino Alexsandro S, Tupinambás Unaí, da Costa Rocha Manoel O, Gonçalves Denise U, Chávez-Fumagalli Miguel A, Christodoulides Myron, Machado-de-Ávila Ricardo A, Coelho Eduardo A F, Pereira Isabela A G
Programa de Pós-Graduação em Ciências da Saúde: Infectologia e Medicina Tropical, Faculdade de Medicina, Universidade Federal de Minas Gerais, Belo Horizonte, 30130-100, Minas Gerais, Brazil.
Programa de Pós-Graduação em Ciências da Saúde: Infectologia e Medicina Tropical, Faculdade de Medicina, Universidade Federal de Minas Gerais, Belo Horizonte, 30130-100, Minas Gerais, Brazil; Fundação Hospitalar do Estado de Minas Gerais, Hospital Eduardo de Menezes, Belo Horizonte, 30622-020, Minas Gerais, Brazil.
Exp Parasitol. 2025 Aug;275:108980. doi: 10.1016/j.exppara.2025.108980. Epub 2025 Jun 23.
Laboratory diagnosis of leishmaniasis is hampered by the variable sensitivity and/or specificity of the tests. In the present study, we developed a new recombinant antigen based on a chimeric protein, called CHIMISA, which was composed of specific B-cell epitopes from Leishmania antigenic proteins recently identified in an immunoproteomics approach using sera samples from visceral leishmaniasis (VL) and VL/HIV co-infected patients. The protein was produced containing specific B-cell epitopes from four parasite proteins (SUZ41772.1, SUZ41881.1, AYU79515.1, and SUZ44007.1) and used as an antigen in ELISA with serum and urine samples for diagnosing VL, tegumentary leishmaniasis (TL), and VL/HIV co-infection. Paired serum and urine samples from healthy subjects and patients with other cross-reactive diseases were also used. The serum-based CHIMISA ELISA had 100 % sensitivity and 98.5 % specificity for diagnosing VL, TL and VL/HIV, with an area under the (AUC) value of 1.0. Soluble Leishmania Antigenic (SLA) extracts of Leishmania (Viannia) braziliensis and SLA of Leishmania (Leishmania) infantum were used as comparative antigens, and showed sensitivity values of 72.0 % and 44.0 %, respectively, and specificity values of 97.5 % and 98.1 %, respectively. The AUC values were 0.90 and 0.91, respectively. In the urine-based CHIMISA ELISA, sensitivity of 99.0 % and specificity of 98.1 % were reached, with an AUC of 0.99. SLA of L. (V.) braziliensis and SLA of L. (L.) infantum showed 65.6 % and 51.1 % sensitivity, respectively; and 96.9 % and 97.1 % specificity, respectively. The AUC values were 0.91 and 0.86, respectively. Although only a limited serological panel was used in this study, our preliminary data suggest that this new chimeric protein could be considered as a diagnostic candidate for VL, TL, and VL/HIV cases, using patient urine and serum.
利什曼病的实验室诊断受到检测方法敏感性和/或特异性变化的阻碍。在本研究中，我们基于一种嵌合蛋白开发了一种新的重组抗原，称为CHIMISA，它由利什曼原虫抗原蛋白的特定B细胞表位组成，这些表位是最近通过免疫蛋白质组学方法，利用来自内脏利什曼病（VL）和VL/HIV合并感染患者的血清样本鉴定出来的。该蛋白含有来自四种寄生虫蛋白（SUZ41772.1、SUZ41881.1、AYU79515.1和SUZ44007.1）的特定B细胞表位，并用作ELISA中的抗原，用于检测血清和尿液样本，以诊断VL、皮肤利什曼病（TL）和VL/HIV合并感染。还使用了来自健康受试者和患有其他交叉反应性疾病患者的配对血清和尿液样本。基于血清的CHIMISA ELISA在诊断VL、TL和VL/HIV时敏感性为100%，特异性为98.5%，曲线下面积（AUC）值为1.0。巴西利什曼原虫（Viannia）的可溶性利什曼原虫抗原（SLA）提取物和婴儿利什曼原虫（Leishmania）的SLA用作对照抗原，其敏感性分别为72.0%和44.0%，特异性分别为97.5%和98.1%。AUC值分别为0.90和0.91。在基于尿液的CHIMISA ELISA中，敏感性达到99.0%，特异性为98.1%，AUC为0.99。巴西利什曼原虫（V.）的SLA和婴儿利什曼原虫（L.）的SLA敏感性分别为65.6%和51.1%；特异性分别为96.9%和97.1%。AUC值分别为0.91和0.86。尽管本研究仅使用了有限的血清学样本，但我们的初步数据表明，这种新的嵌合蛋白可被视为使用患者尿液和血清诊断VL、TL和VL/HIV病例的候选诊断方法。
