B淋巴细胞活化分子事件及相关病理机制
摘要
B cells are important immune cells for humoral immune responses. B cell activation is a critical step for antibody production in response to pathogen invasion. In this review, we focused on the recent achievements in B cell studies using high-resolution high-speed live cell imaging techniques. These studies substantially improve our understanding of the molecular events governing the initiation of B cell activation. We summarized the recent studies about tonic B cell receptor (BCR) signaling which is thought to be responsible for B cell survival. We proposed several models to explain the origin of tonic BCR signaling. Meanwhile, we described the BCR signaling pathway driven by antigen stimulation, and discussed the possible mechanisms initiating B cell activation. Especially, we described how the high-resolution high-speed live cell imaging techniques help scientists to capture the dynamic events during B cell activation. Moreover, we discussed the molecular nature of the memory B cell with special focus placed on the roles of the evolutionarily conserved IgG cytoplasmic tail in memory antibody responses. Abnormal regulation of BCR activation may lead to diseases. In this regard, we discussed the recent findings in the last part of this review and also summarized the relationship of the mutation in the BCR inhibitory co-receptor FcγRIIB and autoimmune diseases. Furthermore, we discussed the relationship between the mutation in BCR signaling molecules and B cell tumor. This work improves our understanding about B cell diseases and may benefit the clinical therapy.