Laboratorio de Inmunología, Vacunas y Alergia, CESyMA, Escuela de Ciencia y Tecnología, Universidad Nacional de San Martín (UNSAM), Buenos Aires, Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina.
Laboratorio de Inmunología Molecular, Instituto de Investigaciones Biotecnológicas, Universidad Nacional de San Martín (UNSAM), Buenos Aires, Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina.
Vaccine. 2021 Feb 5;39(6):933-942. doi: 10.1016/j.vaccine.2020.12.072. Epub 2021 Jan 13.
Toxoplasmosis is a zoonotic disease with worldwide prevalence in humans and warm-blooded animal populations. In livestock Toxoplasma gondii is the causal agent of significant economic losses since it can cause abortions in goats and sheep. It is estimated that one third of the world population is infected. Although there are effective therapies for acute infection, these are sometimes poorly tolerated, teratogenic, and have a long administration time. Considering the deficiencies that exist related to the prevention and treatment of toxoplasmosis, the development of a safe and effective vaccine would be extremely valuable in fighting against this infection. In the present work, we characterize for the first time the adjuvant and immunogenic potential of a recombinant profilin protein (rTgPF), in a vaccine formulation alone or in combination with the well-known GRA7 antigen candidate in a murine toxoplasmosis model. Since TgPF acts as a ligand for TLR11 and 12 inducing innate immune responses that promote type 1 adaptive responses, we first study the capacity of the mix rGRA7 + rTgPF to initiate an immune response by evaluating dendritic cell activation. Both rTgPF and rGRA7 induces activation of mouse BMDCs more efficiently than the single proteins, evidenced by increased expression of CD80 and CD86 co-stimulatory proteins and secretion of IL-6, IL-10 and IL-12 cytokines after in vitro stimulation. The sum of the effects of rGRA7 and rTgPF on BMDCs maturation led us to assay them in a vaccination protocol. BALB/c mice vaccinated with this mix elicited a Th1-biased immunity via the induction of lymphocyte proliferation, activation of CD4T cells and increased IFN-γ production that resulted in enhanced protection against chronic Toxoplama gondii infection. Profilin per se induce only cellular immunity but augments the effect of rGRA7 immune responses when used together, thus allowing us to postulate rTgPF as a potential adjuvant in a protein vaccine.
弓形虫病是一种具有世界范围流行的人畜共患病，可感染人类和温血动物。在畜牧业中，弓形虫是造成重大经济损失的病原体，因为它可以导致山羊和绵羊流产。据估计，世界上有三分之一的人口感染了这种疾病。虽然有有效的急性感染治疗方法，但这些方法有时耐受性差、致畸，并且需要长时间的给药。考虑到在弓形虫病的预防和治疗方面存在的缺陷，开发一种安全有效的疫苗对于对抗这种感染将是非常有价值的。在本工作中，我们首次描述了重组原肌球蛋白蛋白（rTgPF）作为佐剂和免疫原性的潜力，在一种疫苗制剂中单独使用或与众所周知的 GRA7 候选抗原联合使用，在小鼠弓形虫病模型中。由于 TgPF 作为 TLR11 和 12 的配体发挥作用，诱导先天免疫反应，促进 1 型适应性反应，我们首先通过评估树突状细胞的激活来研究混合 rGRA7+rTgPF 引发免疫反应的能力。rTgPF 和 rGRA7 都比单一蛋白更有效地诱导小鼠 BMDC 的激活，这表现在体外刺激后共刺激蛋白 CD80 和 CD86 的表达增加以及细胞因子 IL-6、IL-10 和 IL-12 的分泌增加。rGRA7 和 rTgPF 对 BMDC 成熟的综合作用使我们能够在疫苗接种方案中检测它们。用这种混合物接种的 BALB/c 小鼠通过诱导淋巴细胞增殖、激活 CD4T 细胞和增加 IFN-γ 的产生，引发了 Th1 偏向性免疫，从而增强了对慢性弓形虫感染的保护。原肌球蛋白本身仅诱导细胞免疫，但当与 rGRA7 免疫反应一起使用时会增强其效果，因此我们可以假设 rTgPF 是一种潜在的蛋白疫苗佐剂。
