Patgaonkar Mandar, Herbert Fabien, Powale Krushali, Gandhe Prajakta, Gogtay Nithya, Thatte Urmila, Pied Sylviane, Sharma Shobhona, Pathak Sulabha
Department of Biological Sciences, Tata Institute of Fundamental Research, Mumbai, India.
Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019 - UMR 8204 - CIIL - Centre d'Infection et d'Immunité de Lille, Lille, France.
Parasite Immunol. 2018 Oct;40(10):e12580. doi: 10.1111/pim.12580. Epub 2018 Sep 11.
B cell-mediated humoral responses are essential for controlling malarial infection. Studies have addressed the effects of Plasmodium falciparum infection on peripheral B-cell subsets but not much is known for P. vivax infection. Furthermore, majority of the studies investigate changes during acute infection, but not after parasite clearance. In this prospective study, we analysed peripheral B-cell profiles and antibody responses during acute P. vivax infection and upon recovery (30 days post-treatment) in a low-transmission area in India. Dengue patients were included as febrile-condition controls. Both dengue and malaria patients showed a transient increase in atypical memory B cells during acute infection. However, transient B cell-activating factor (BAFF)-independent increase in the percentage of total and activated immature B cells was observed in malaria patients. Naïve B cells from malaria patients also showed increased TLR4 expression. Total IgM levels remained unchanged during acute infection but increased significantly at recovery. Serum antibody profiling showed a parasite-specific IgM response that persisted at recovery. A persistent IgM autoantibody response was also observed in malaria but not dengue patients. Our data suggest that in hypoendemic regions acute P. vivax infection skews peripheral B-cell subsets and results in a persistent parasite-specific and autoreactive IgM response.
B细胞介导的体液免疫反应对于控制疟疾感染至关重要。已有研究探讨了恶性疟原虫感染对外周B细胞亚群的影响，但对于间日疟原虫感染的了解却不多。此外，大多数研究调查的是急性感染期间的变化，而非寄生虫清除后的情况。在这项前瞻性研究中，我们分析了印度一个低传播地区急性间日疟原虫感染期间及康复后（治疗后30天）的外周B细胞谱和抗体反应。登革热患者作为发热状况对照纳入研究。登革热和疟疾患者在急性感染期间非典型记忆B细胞均出现短暂增加。然而，在疟疾患者中观察到总B细胞和活化未成熟B细胞百分比出现短暂的不依赖B细胞活化因子（BAFF）的增加。疟疾患者的初始B细胞也显示Toll样受体4（TLR4）表达增加。急性感染期间总IgM水平保持不变，但在康复时显著升高。血清抗体谱显示出一种寄生虫特异性IgM反应，该反应在康复时持续存在。在疟疾患者中还观察到持续的IgM自身抗体反应，但登革热患者未出现。我们的数据表明，在低流行地区，急性间日疟原虫感染会使外周B细胞亚群发生偏移，并导致持续的寄生虫特异性和自身反应性IgM反应。
