B lymphocytes exit lymph nodes through cortical lymphatic sinusoids by a mechanism independent of sphingosine-1-phosphate-mediated chemotaxis.
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ABSTRACT:
SUBMITTER: Sinha RK
PROVIDER: S-EPMC2744325 | biostudies-literature | 2009 Mar
REPOSITORIES: biostudies-literature
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B lymphocytes exit lymph nodes through cortical lymphatic sinusoids by a mechanism independent of sphingosine-1-phosphate-mediated chemotaxis.
Sinha Rajesh K RK Park Chung C Hwang Il-Young IY Davis Michael D MD Kehrl John H JH
Immunity 20090219 3
Sphingosine-1-phosphate (S1P) helps mediate lymphocyte egress from lymph nodes, yet many mechanistic questions remain. Here, we show the presence of B lymphocyte egress sites located in the lymph node cortex close to lymph node follicles. B cells exited lymph nodes by squeezing through apparent portals in the lymphatic endothelium of these sinusoids. Treatment with the S1P receptor agonist FTY720 emptied the cortical sinusoids of lymphocytes, blocked lymphatic endothelial penetration, and displa ...[more]
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