Vale Danniele L, Freitas Camila S, Martins Vívian T, Moreira Gabriel J L, Machado Amanda S, Ramos Fernanda F, Pereira Isabela A G, Bandeira Raquel S, de Jesus Marcelo M, Tavares Grasiele S V, Ludolf Fernanda, Chávez-Fumagalli Miguel A, Galdino Alexsandro S, Fujiwara Ricardo T, Bueno Lílian L, Roatt Bruno M, Christodoulides Myron, Coelho Eduardo A F, Lage Daniela P
Programa de Pós-Graduação em Ciências da Saúde: Infectologia e Medicina Tropical, Faculdade de Medicina, Universidade Federal de Minas Gerais, Belo Horizonte 30130-100, Minas Gerais, Brazil.
Laboratório de Imunopatologia, Núcleo de Pesquisas em Ciências Biológicas/NUPEB, Departamento de Ciências Biológicas, Insituto de Ciências Exatas e Biológicas, Universidade Federal de Ouro Preto, Ouro Preto 35400-000, Minas Gerais, Brazil.
Biology (Basel). 2023 Jun 13;12(6):851. doi: 10.3390/biology12060851.
Visceral leishmaniasis (VL) in the Americas is a chronic systemic disease caused by infection with parasites. The toxicity of antileishmanial drugs, long treatment course and limited efficacy are significant concerns that hamper adequate treatment against the disease. Studies have shown the promise of an immunotherapeutics approach, combining antileishmanial drugs to reduce the parasitism and vaccine immunogens to activate the host immune system. In the current study, we developed an immunotherapy using a recombinant T cell epitope-based chimeric protein, ChimT, previously shown to be protective against , with the adjuvant monophosphoryl lipid A (MPLA) and amphotericin B (AmpB) as the antileishmanial drug. BALB/c mice were infected with stationary promastigotes and later they received saline or were treated with AmpB, MPLA, ChimT/Amp, ChimT/MPLA or ChimT/MPLA/AmpB. The combination of ChimT/MPLA/AmpB significantly reduced the parasite load in mouse organs ( < 0.05) and induced a Th1-type immune response, which was characterized by higher ratios of anti-ChimT and anti-parasite IgG2a:IgG1 antibodies, increased IFN-γ mRNA and IFN-γ and IL-12 cytokines and accompanied by lower levels of IL-4 and IL-10 cytokines, when compared to other treatments and controls (all < 0.05). Organ toxicity was also lower with the ChimT/MPLA/AmpB immunotherapy, suggesting that the inclusion of the vaccine and adjuvant ameliorated the toxicity of AmpB to some degree. In addition, the ChimT vaccine alone stimulated in vitro murine macrophages to significantly kill three different internalized species of parasites and to produce Th1-type cytokines into the culture supernatants. To conclude, our data suggest that the combination of ChimT/MPLA/AmpB could be considered for further studies as an immunotherapy for infection.
美洲内脏利什曼病（VL）是一种由寄生虫感染引起的慢性全身性疾病。抗利什曼原虫药物的毒性、漫长的治疗疗程以及有限的疗效是阻碍该疾病得到充分治疗的重大问题。研究表明免疫治疗方法具有前景，即将抗利什曼原虫药物与疫苗免疫原相结合，以减少寄生虫感染并激活宿主免疫系统。在本研究中，我们研发了一种免疫疗法，使用基于重组T细胞表位的嵌合蛋白ChimT（先前已证明其对[具体病原体]具有保护作用），佐剂单磷酰脂质A（MPLA）以及两性霉素B（AmpB）作为抗利什曼原虫药物。BALB/c小鼠感染[具体病原体]静止前鞭毛体，随后接受生理盐水处理或用AmpB、MPLA、ChimT/Amp、ChimT/MPLA或ChimT/MPLA/AmpB进行治疗。与其他治疗组和对照组相比，ChimT/MPLA/AmpB组合显著降低了小鼠器官中的寄生虫负荷（P<0.05），并诱导了Th1型免疫反应，其特征为抗ChimT和抗寄生虫IgG2a:IgG1抗体比例更高、IFN-γ mRNA以及IFN-γ和IL-12细胞因子增加，同时伴有IL-4和IL-10细胞因子水平降低（所有P<0.05）。ChimT/MPLA/AmpB免疫疗法的器官毒性也较低，这表明加入疫苗和佐剂在一定程度上减轻了AmpB的毒性。此外，单独的ChimT疫苗在体外刺激小鼠巨噬细胞显著杀死三种不同内化的[具体病原体]物种，并在培养上清液中产生Th1型细胞因子。总之，我们的数据表明ChimT/MPLA/AmpB组合可作为[具体病原体]感染的免疫疗法考虑进一步研究。
