Academy of Scientific and Innovative Research (AcSIR), Noida, India.
Division of Immunology, National Institute of Malaria Research, Dwarka, New Delhi, India.
Int Rev Immunol. 2024;43(5):309-325. doi: 10.1080/08830185.2024.2336539. Epub 2024 Apr 15.
Cerebral malaria (CM) is a severe complication of infection, with complex pathogenesis involving multiple factors, including the host's immunological response. T lymphocytes, specifically CD4+ T helper cells and CD8+ cytotoxic T cells, are crucial in controlling parasite growth and activating cells for parasite clearance cytokine secretion. Contrary to this, reports also suggest the pathogenic nature of T lymphocytes as they are often involved in disease progression and severity. CD8+ cytotoxic T cells migrate to the host's brain vasculature, disrupting the blood-brain barrier and causing neurological manifestations. CD4+ T helper cells on the other hand play a variety of functions as they differentiate into different subtypes which may function as pro-inflammatory or anti-inflammatory. The excessive pro-inflammatory response in CM can lead to multi-organ failure, necessitating a check mechanism to maintain immune homeostasis. This is achieved by regulatory T cells and their characteristic cytokines, which counterbalance the pro-inflammatory immune response. Maintaining a critical balance between pro and anti-inflammatory responses is crucial for determining disease outcomes in CM. A slight change in this balance may contribute to a disease severity owing to an extreme inflammatory response or unrestricted parasite growth, a potential target for designing immunotherapeutic treatment approaches. The review briefly discusses the pathogenesis of CM and various mechanisms responsible for the disruption of the blood-brain barrier. It also highlights the role of different T cell subsets during infection and emphasizes the importance of balance between pro and anti-inflammatory T cells that ultimately decides the outcome of the disease.
脑型疟疾(CM)是一种严重的疟疾感染并发症,其发病机制复杂,涉及多个因素,包括宿主的免疫反应。T 淋巴细胞,特别是 CD4+辅助性 T 细胞和 CD8+细胞毒性 T 细胞,在控制寄生虫生长和激活细胞清除寄生虫方面起着至关重要的作用,并分泌细胞因子。然而,与这一观点相反的是,报告还表明 T 淋巴细胞具有致病性,因为它们通常参与疾病的进展和严重程度。CD8+细胞毒性 T 细胞迁移到宿主的脑血管系统,破坏血脑屏障并导致神经表现。另一方面,CD4+辅助性 T 细胞发挥多种功能,因为它们分化为不同的亚型,可能具有促炎或抗炎作用。CM 中的过度促炎反应可导致多器官衰竭,因此需要一种检查机制来维持免疫稳态。这是通过调节性 T 细胞及其特征性细胞因子来实现的,它们可以平衡促炎免疫反应。在 CM 中,维持促炎和抗炎反应之间的关键平衡对于确定疾病结局至关重要。这种平衡的微小变化可能会导致疾病严重程度的变化,原因是炎症反应过度或寄生虫生长不受限制,这可能成为设计免疫治疗方法的一个潜在靶点。本综述简要讨论了 CM 的发病机制以及导致血脑屏障破坏的各种机制。它还强调了不同 T 细胞亚群在感染过程中的作用,并强调了促炎和抗炎 T 细胞之间平衡的重要性,这最终决定了疾病的结局。