Laboratory of Parasitology, National School of Veterinary Medicine, University La Manouba, 2020, Sidi, Thabet, Tunisia.
Laboratory of BioInformatics, BioMathematics and BioStatistics, LR16 IPT09, Institute Pasteur of Tunis, University of Tunis El Manar, Tunisia.
Acta Trop. 2021 Jun;218:105906. doi: 10.1016/j.actatropica.2021.105906. Epub 2021 Mar 26.
The first step of the diagnostic process of canine leishmaniasis (CanL) is initiated by veterinarians and relies on their assessment of a high number of clinical signs common to other infectious diseases. We investigated herein the relationship between the clinical profile of 64 domestic dogs living in Tunisian endemic areas and their serological immune status with the aim to identify leishmanial serological markers of diagnosis and disease staging. Seven clinical signs were examined and a total clinical score that describes the number (TCS1) and the number plus the intensity of the clinical signs (TCS2) were determined. Laboratory tests consisted of parasitological examination (PE) of Giemsa-stained popliteal lymph node smears, indirect fluorescent antibody test (IFAT), IgG-, IgG1-, IgG2-Enzyme-Linked-Immunosorbent-Assay (ELISA), and IgG1-, IgG2- Western blotting (WB). Dogs' categorization according to the results of routine diagnostic tests, the TCS1 and TCS2, and the relative IgG1 and IgG2 specific reactivity allowed us to show that active CanL is characterized by an increased reactivity of the IgG2 specific antibodies. Interestingly, the IgG1 levels increased in parallel with the TCS1 and especially with the TCS2, indicating that this isotype is a better marker of dogs' health deterioration. PE & IFAT positive dogs which presented the highest TCS2 and IgG1 reactivity demonstrated significantly more severe weight loss and paleness of the mucosal membranes, suggesting that these signs characterize the latest stages of the disease. WB analysis showed that threeleishmanial polypeptides merit attention and further investigations. The antigens with MWs 32kDa reacting with IgG1 and 37kDa reacting withIgG2 antibodies were found associated with the results of diagnostic tests and late CanL stages, whereas the 24kDa antigen reacting with the IgG2 isotype and associated with low TCS2 seems to be a marker of the early stages.
犬利什曼病（CanL）的诊断过程首先由兽医启动，依赖于他们对许多常见于其他传染病的临床症状的评估。我们在此调查了居住在突尼斯流行地区的 64 只家养犬的临床特征与其血清免疫状态之间的关系，目的是确定用于诊断和疾病分期的利什曼血清学标志物。检查了 7 种临床症状，并确定了描述数量（TCS1）和数量加临床症状强度（TCS2）的总临床评分。实验室检测包括 Giemsa 染色的腘淋巴结涂片的寄生虫学检查（PE）、间接荧光抗体试验（IFAT）、IgG-、IgG1-、IgG2-酶联免疫吸附试验（ELISA）以及 IgG1-、IgG2- 免疫印迹（WB）。根据常规诊断测试、TCS1 和 TCS2 以及相对 IgG1 和 IgG2 特异性反应性对犬进行分类，表明活跃的 CanL 特征在于 IgG2 特异性抗体的反应性增加。有趣的是，IgG1 水平与 TCS1 特别是 TCS2 平行增加，表明这种同种型是犬健康恶化的更好标志物。PE 和 IFAT 阳性且具有最高 TCS2 和 IgG1 反应性的犬表现出明显更严重的体重减轻和黏膜苍白，表明这些迹象是疾病晚期的特征。WB 分析表明，三种利什曼原虫多肽值得关注和进一步研究。MW 为 32kDa 的抗原与 IgG1 反应，MW 为 37kDa 的抗原与 IgG2 抗体反应，与诊断测试和晚期 CanL 阶段相关，而与 IgG2 同种型反应且与低 TCS2 相关的 24kDa 抗原似乎是早期阶段的标志物。
