Laboratório de Imunoparasitologia, Instituto Oswaldo Cruz (IOC), Fundação Oswaldo Cruz, (Fiocruz), Rio de Janeiro, RJ, Brazil.
Laboratório de Pesquisa em Malária, IOC, Fiocruz, Rio de Janeiro, RJ, Brazil.
Sci Rep. 2024 Nov 9;14(1):27343. doi: 10.1038/s41598-024-72671-x.
Plasmodium vivax, a challenging species to eliminate, causes millions of malaria cases globally annually. Developing an effective vaccine is crucial in the fight against vivax malaria, but considering the limited number of studies focusing on the identification and development of P. vivax-specific vaccine candidates, exploring new antigens is an urgent need. The merozoite protein CyRPA is essential for P. falciparum growth and erythrocyte invasion and corresponds to a promising candidate antigen. In P. vivax, a single study with multiple vaccine candidates indicates PvCyRPA with strong association with protection, outperforming classic malaria vaccine candidates. However, little is known about the specific naturally acquired response in the Americas, as well as the antigen epitope mapping. For this reason, we aimed to investigate the cellular and humoral immune response elicited against PvCyRPA in Brazilian endemic areas to identify the existence of immunodominant regions and the potential of this protein as a single or even a multi-stage specific malaria vaccine candidate for P. vivax. The results demonstrated that PvCyRPA is naturally immunogenic in Brazilian Amazon individuals previously exposed to malaria, which presented anti-PvCyRPA cytophilic antibodies. Moreover, our data show that the protein also possesses important immunogenic regions with an overlap of B and T cell epitopes. These data reinforce the possibility of including PvCyRPA in vaccine formulations for P. vivax.
疟原虫 vivax，一种难以消除的物种，每年在全球范围内导致数百万例疟疾。开发有效的疫苗对于对抗 vivax 疟疾至关重要，但考虑到关注鉴定和开发 vivax 疟原虫特异性疫苗候选物的研究数量有限，探索新的抗原是当务之急。裂殖子蛋白 CyRPA 对于恶性疟原虫的生长和红细胞入侵至关重要，是一个很有前途的候选抗原。在 vivax 疟原虫中，一项针对多个疫苗候选物的单一研究表明，PvCyRPA 与保护有很强的关联，优于经典的疟疾疫苗候选物。然而，关于美洲的特定自然获得性反应以及抗原表位映射，我们知之甚少。出于这个原因，我们旨在调查巴西流行地区针对 PvCyRPA 引起的细胞和体液免疫反应，以确定是否存在免疫优势区域，以及该蛋白是否可作为 vivax 疟原虫的单一甚至多阶段特异性疟疾疫苗候选物。结果表明，先前接触过疟疾的巴西亚马逊个体对 PvCyRPA 具有天然的免疫原性，这些个体表现出抗 PvCyRPA 细胞亲嗜性抗体。此外，我们的数据表明，该蛋白还具有重要的免疫原性区域，具有 B 细胞和 T 细胞表位的重叠。这些数据强化了将 PvCyRPA 纳入 vivax 疟原虫疫苗制剂的可能性。
