Fasquelle François, Scuotto Angelo, Vreulx Anaïs-Camille, Petit Thierry, Charpentier Thomas, Betbeder Didier
Vaxinano SAS, 84 rue du Dr Yersin, 59120, Loos, France.
Zoo de La Palmyre, 6 avenue de Royan, 17570, Les Mathes, France.
Int J Parasitol Parasites Wildl. 2023 Sep 7;22:69-74. doi: 10.1016/j.ijppaw.2023.09.002. eCollection 2023 Dec.
is an intracellular protozoon found worldwide, which completes its life cycle between felids (its definitive host) and other warm-blooded animals. While the infection rarely leads to severe complications in humans, many animal species are very susceptible to this infection, for example the squirrel monkey () which is the subject of this study. Toxoplasmosis is lethal for 80% of cases in this species, and fatal outbreaks are frequently reported in zoological parks. No efficient treatment exists, but a new vaccine prepared with maltodextrin nanoparticles containing killed antigens has been tested recently in French zoos. The animals were immunized through heterologous administrations, with two nasal doses at one-month interval, followed by nasal/subcutaneous boosts thereafter. No death has been reported since the beginning of this vaccination campaign, but we felt the protocol could be simplified. Here, an improved and less-invasive immunization protocol was evaluated on 6 in the French zoo La Palmyre. It consisted of two nasal administrations at one-month interval, followed by a nasal boost at 6 months. A specific memory T-cell immunity was observed by ELISPOT after two administrations in all the animals, without humoral responses. The results suggest that 2 nasal administrations induce a protective immune response against infection and might be sufficient to induce a strong Tcell memory, further improving immunity.
是一种在全球范围内发现的细胞内原生动物，其在猫科动物（其终末宿主）和其他温血动物之间完成生命周期。虽然该感染在人类中很少导致严重并发症，但许多动物物种对这种感染非常敏感，例如本研究的对象松鼠猴。弓形虫病在该物种中80%的病例是致命的，动物园中经常报告致命疫情。目前没有有效的治疗方法，但最近在法国动物园对一种用含有灭活抗原的麦芽糊精纳米颗粒制备的新疫苗进行了测试。通过异源给药对动物进行免疫，每隔一个月鼻腔给药两次，之后进行鼻腔/皮下加强免疫。自这次疫苗接种运动开始以来，没有死亡报告，但我们认为方案可以简化。在此，在法国拉帕尔米尔动物园对6只松鼠猴评估了一种改进的、侵入性较小的免疫方案。该方案包括每隔一个月进行两次鼻腔给药，然后在6个月时进行一次鼻腔加强免疫。在所有动物进行两次给药后，通过ELISPOT观察到特异性记忆T细胞免疫，没有体液反应。结果表明，两次鼻腔给药可诱导针对弓形虫感染的保护性免疫反应，可能足以诱导强烈的T细胞记忆，进一步提高免疫力。
