Cosmc controls B cell homing


Zeng J, Eljalby M, Aryal RP, Lehoux S, Stavenhagen K, Kudelka MR, Wang Y, Wang J, Ju T, von Andrian UH, et al. Cosmc controls B cell homing. Nat Commun. 2020;11 (1) :3990.

Date Published:

2020 08 10


The molecular mechanisms regulating lymphocyte homing into lymph nodes are only partly understood. Here, we report that B cell-specific deletion of the X-linked gene, Cosmc, and the consequent decrease of protein O-glycosylation, induces developmental blocks of mouse B cells. After transfer into wild-type recipient, Cosmc-null B cells fail to home to lymph nodes as well as non-lymphoid organs. Enzymatic desialylation of wild-type B cells blocks their migration into lymph nodes, indicating a requirement of sialylated O-glycans for proper trafficking. Mechanistically, Cosmc-deficient B cells have normal rolling and firm arrest on high endothelium venules (HEV), thereby attributing their inefficient trafficking to alterations in the subsequent transendothelial migration step. Finally, Cosmc-null B cells have defective chemokine signaling responses. Our results thus demonstrate that Cosmc and its effects on O-glycosylation are important for controlling B cell homing.