Viana Kelvinson Fernandes, Lacerda Giulia, Teixeira Natália Soares, Rodrigues Cangussu Alex Sander, Sousa Aguiar Raimundo Wagner, Giunchetti Rodolfo Cordeiro
Interdisciplinary Center for Life Sciences and Nature, Federal University of Latin American Integration (UNILA), Foz do Iguaçu, PR, Brazil; Laboratory of Biomolecules and Vaccines, Agrarian Sciences and Technologic Department, Federal University of Tocantins (UFT), Gurupi, Tocantins, Brazil.
Laboratory of Biomolecules and Vaccines, Agrarian Sciences and Technologic Department, Federal University of Tocantins (UFT), Gurupi, Tocantins, Brazil.
Vet Parasitol. 2018 Apr 30;254:98-104. doi: 10.1016/j.vetpar.2018.03.010. Epub 2018 Mar 11.
A key goal in the control of canine visceral leishmaniosis (CVL) has been the development of vaccines with a highly protective capability to interrupt the parasite transmission cycle. However, in addition to promising vaccine searches, researchers have sought to develop new drugs capable of eliminating parasites in humans and dogs. With that in mind, this study analyzed an immunotherapeutic approach in dogs naturally infected with Leishmania infantum. Fourteen dogs were divided into two groups and received a protocol of immunotherapeutic treatment with five doses of total antigens of Leishmania amazonensis or total antigens of L. amazonensis plus saponin (LaSap). All the animals were evaluated before and 90 and 180 days after treatment, hematology, liver and renal biochemical analyzes, serology, lymphoproliferation, and parasite load by qPCR. The results of immunotherapy with the LaSap vaccine were promising since it was able to preserve hematological and biochemical parameters, as well as improve the clinical status, reduce serum levels of IgG, induce a lymphoproliferative capacity against soluble antigens of L. infantum, and provide a marked reduction in the parasite load after LaSap immunotherapeutic treatment. The immunotherapy data demonstrated that LaSap offered the best formulation to induce clinical cure associated with a parasite load reduction in the skin. However, after 180 days of treatment, the animals again showed a slight increase in parasitism, indicating that immunotherapy does not promote sterilizing cure and a new immunotherapeutic intervention would be necessary to maintain low parasitism in dogs.
犬内脏利什曼病（CVL）控制的一个关键目标是开发具有高度保护能力的疫苗，以中断寄生虫传播周期。然而，除了进行有前景的疫苗研究外，研究人员还试图开发能够消除人和犬体内寄生虫的新药。考虑到这一点，本研究分析了对自然感染婴儿利什曼原虫的犬采用的一种免疫治疗方法。将14只犬分为两组，接受免疫治疗方案，分别注射五剂亚马逊利什曼原虫的总抗原或亚马逊利什曼原虫总抗原加皂苷（LaSap）。在治疗前以及治疗后90天和180天对所有动物进行评估，包括血液学、肝脏和肾脏生化分析、血清学、淋巴细胞增殖以及通过qPCR检测寄生虫载量。LaSap疫苗免疫治疗的结果很有前景，因为它能够维持血液学和生化参数，改善临床状况，降低IgG血清水平，诱导针对婴儿利什曼原虫可溶性抗原的淋巴细胞增殖能力，并在LaSap免疫治疗后显著降低寄生虫载量。免疫治疗数据表明，LaSap提供了最佳配方，可诱导临床治愈并降低皮肤中的寄生虫载量。然而，治疗后第180天，动物的寄生虫感染率再次略有上升，这表明免疫治疗不能促进灭菌治愈，需要新的免疫治疗干预措施来维持犬体内低水平的寄生虫感染。
