CXCR4 and a cell-extrinsic mechanism control immature B lymphocyte egress from bone marrow.

ABSTRACT: Leukocyte residence in lymphoid organs is controlled by a balance between retention and egress-promoting chemoattractants sensed by pertussis toxin (PTX)-sensitive Gαi protein-coupled receptors (GPCRs). Here, we use two-photon intravital microscopy to show that immature B cell retention within bone marrow (BM) was strictly dependent on amoeboid motility mediated by CXCR4 and CXCL12 and by α4β1 integrin-mediated adhesion to VCAM-1. However, B lineage cell egress from BM is independent of PTX-sensitive GPCR signaling. B lineage cells expressing PTX rapidly exited BM even though their motility within BM parenchyma was significantly reduced. Our experiments reveal that when immature B cells are near BM sinusoids their motility is reduced, their morphology is predominantly rounded, and cells re

SUBMITTER: Beck TC 

PROVIDER: S-EPMC4267240 | biostudies-literature | 2014 Dec

REPOSITORIES: biostudies-literature