Vascular Immunology Unit, Department of Pathology and Bosch Institute, Sydney Medical School, The University of Sydney, New South Wales, Australia.
PLoS Pathog. 2010 Jul 29;6(7):e1001021. doi: 10.1371/journal.ppat.1001021.
Cerebral malaria, a major cause of death during malaria infection, is characterised by the sequestration of infected red blood cells (IRBC) in brain microvessels. Most of the molecules implicated in the adhesion of IRBC on endothelial cells (EC) are already described; however, the structure of the IRBC/EC junction and the impact of this adhesion on the EC are poorly understood. We analysed this interaction using human brain microvascular EC monolayers co-cultured with IRBC. Our study demonstrates the transfer of material from the IRBC to the brain EC plasma membrane in a trogocytosis-like process, followed by a TNF-enhanced IRBC engulfing process. Upon IRBC/EC binding, parasite antigens are transferred to early endosomes in the EC, in a cytoskeleton-dependent process. This is associated with the opening of the intercellular junctions. The transfer of IRBC antigens can thus transform EC into a target for the immune response and contribute to the profound EC alterations, including peri-vascular oedema, associated with cerebral malaria.
脑疟疾是疟疾感染期间的主要死亡原因,其特征是感染的红细胞(IRBC)在脑微血管中被隔离。已经描述了大多数与 IRBC 在内皮细胞(EC)上黏附相关的分子;然而,IRBC/EC 连接处的结构以及这种黏附对 EC 的影响知之甚少。我们使用与人脑微血管 EC 单层共培养的 IRBC 分析了这种相互作用。我们的研究表明,在类似于血影细胞吞噬的过程中,物质从 IRBC 转移到脑 EC 质膜,随后是 TNF 增强的 IRBC 吞噬过程。在 IRBC/EC 结合后,寄生虫抗原通过依赖于细胞骨架的过程被转移到 EC 的早期内体中。这与细胞间连接的打开有关。因此,IRBC 抗原的转移可以使 EC 成为免疫反应的靶标,并有助于与脑疟疾相关的 EC 深刻改变,包括血管周围水肿。