Programa de Pós-Graduação em Ciências da Saúde: Infectologia e Medicina Tropical, Faculdade de Medicina, Universidade Federal de Minas Gerais, Belo Horizonte, 30.130-100, Minas Gerais, Brazil.
Secretaria Municipal de Saúde, Prefeitura Municipal de Igarapé. Igarapé, Minas Gerais, Brazil.
Acta Trop. 2021 Dec;224:106126. doi: 10.1016/j.actatropica.2021.106126. Epub 2021 Sep 16.
Laboratory diagnosis of leishmaniasis shows variable efficacy in detecting infected mammalian hosts and there is a need to identify suitable antigens to improve the accuracy of diagnostic tests. In the present study, a L. infantum hypothetical protein called LiHyQ was evaluated for the diagnosis of tegumentary (TL) and visceral (VL) leishmaniasis using canine and human samples. A collection of dog sera (n=155) were tested and contained samples from asymptomatic (n=20) and symptomatic (n=25) VL animals, from healthy dogs living in endemic (n=25) or non-endemic (n=25) areas of disease, from Leish-Tec® vaccinated dogs (n=20) or from dogs infected with Ehrlichia canis (n=15), Babesia canis (n=10) and Trypanosoma cruzi (n=15). Sensitivity (Se), Specificity (Sp), Positive Predictive Value (PPV) and Negative Predictive Value (NPV) of 100% were observed for rLiHyQ with these samples, whereas the Se, Sp, PPV and NPV values with L. infantum Soluble Leishmania Antigen (SLA) preparation were 60.0%, 99.0%, 96.0% and 86.0%, respectively. A collection of human sera (n=305) were tested and contained samples from TL (n=50) and VL (n=40) patients, from VL/HIV co-infected patients (n=35), from patients infected with HIV alone (n=30), Chagas Disease (n=30), malaria (n=10), tuberculosis (n=10), paracoccidioidomycosis (n=15), leprosy (n=30) or aspergillosis (n=15); and from healthy subjects (n=40). Se, Sp, PPV and NPV values of 100% were observed for rLiHyQ with these samples, whereas the Se, Sp, PPV and NPV values with SLA were 58.0%, 76.0%, 50.0% and 82.0%, respectively. The antibody reactivity against the protein was compared with commercial kits, and the kappa index varied from 0.95 to 1.00 for rLiHyQ, and of 0.55 to 0.82 for the kits. In addition, the serological follow-up of treated patients showed a significant reduction in rLiHyQ-specific IgG antibody levels. All canine and human samples were tested at the same time using the same reagents, in order to reduce experimental variation and interference in data interpretation. In conclusion, our preliminary data suggest a diagnostic and prognostic role for rLiHyQ against leishmaniasis.
利什曼原虫假设蛋白 LiHyQ 用于诊断皮肤利什曼病和内脏利什曼病的初步研究
实验室诊断利什曼病在检测感染的哺乳动物宿主方面显示出不同的效果，因此需要鉴定合适的抗原以提高诊断试验的准确性。在本研究中，评估了利什曼原虫假设蛋白 LiHyQ 用于诊断皮肤利什曼病和内脏利什曼病，使用了犬和人样本。收集了一组犬血清（n=155），其中包含无症状（n=20）和有症状（n=25）内脏利什曼病动物、来自流行（n=25）或非流行（n=25）地区的健康犬、Leish-Tec®疫苗接种的犬（n=20）或感染埃立克体（n=15）、犬巴贝斯虫（n=10）和克氏锥虫（n=15）的犬的血清。rLiHyQ 对这些样本的敏感性（Se）、特异性（Sp）、阳性预测值（PPV）和阴性预测值（NPV）均为 100%，而利什曼原虫可溶性抗原（SLA）制剂的 Se、Sp、PPV 和 NPV 值分别为 60.0%、99.0%、96.0%和 86.0%。收集了一组人血清（n=305），其中包含皮肤利什曼病（n=50）和内脏利什曼病（n=40）患者、内脏利什曼病/艾滋病毒合并感染患者（n=35）、单独感染艾滋病毒的患者（n=30）、恰加斯病（n=30）、疟疾（n=10）、结核病（n=10）、副球孢子菌病（n=15）、麻风病（n=30）或曲霉病（n=15）患者以及健康对照（n=40）。rLiHyQ 对这些样本的 Se、Sp、PPV 和 NPV 值均为 100%，而 SLA 的 Se、Sp、PPV 和 NPV 值分别为 58.0%、76.0%、50.0%和 82.0%。将针对该蛋白的抗体反应与商业试剂盒进行了比较，rLiHyQ 的kappa 指数为 0.95-1.00，而试剂盒的 kappa 指数为 0.55-0.82。此外，治疗患者的血清学随访显示 rLiHyQ 特异性 IgG 抗体水平显著降低。所有犬和人样本均同时使用相同的试剂进行检测，以减少实验变异性并避免数据解释的干扰。总之，我们的初步数据表明 rLiHyQ 对利什曼病具有诊断和预后作用。
