Figure 2.

Altered BCR-antigen endocytosis, trafficking and presentation in B cell autoimmunity and malignancy. Autoimmunity. BCR-mediated self-antigen uptake can increase presentation of relevant peptides and drive disease progression. B cells in many autoimmune disorders exhibit increased surface MHC-II expression, though the repertoire of presented peptides has not been addressed. Malignancy. Following antigen binding to the BCR, a signaling cascade is initiated through phosphorylation of Igα/β ITAMs residues. Downstream activation of ERK and AKT mediates many metabolic changes and survival signaling, which are dysregulated in B cell malignancies due to localization and trafficking dynamics of the BCR. Created with BioRender.com.