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Fibroblastic reticular cells guide T lymphocyte entry into and migration within the splenic T cell zone.

ABSTRACT: Although a great deal is known about T cell entry into lymph nodes, much less is understood about how T lymphocytes access the splenic white pulp (WP). We show in this study that, as recently described for lymph nodes, fibroblastic reticular cells (FRCs) form a network in the T cell zone (periarteriolar lymphoid sheath, PALS) of the WP on which T lymphocytes migrate. This network connects the PALS to the marginal zone (MZ), which is the initial site of lymphocyte entry from the blood. T cells do not enter the WP at random locations but instead traffic to that site using the FRC-rich MZ bridging channels (MZBCs). These data reveal that FRCs form a substrate for T cells in the spleen, guiding these lymphocytes from their site of entry in the MZ into the PALS, within which they continue to move on the same network.

SUBMITTER: Bajenoff M

PROVIDER: S-EPMC2596721 | biostudies-literature | 2008 Sep

REPOSITORIES: biostudies-literature

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Fibroblastic reticular cells guide T lymphocyte entry into and migration within the splenic T cell zone.

Bajénoff Marc M Glaichenhaus Nicolas N Germain Ronald N RN

Journal of immunology (Baltimore, Md. : 1950) 20080901 6

Although a great deal is known about T cell entry into lymph nodes, much less is understood about how T lymphocytes access the splenic white pulp (WP). We show in this study that, as recently described for lymph nodes, fibroblastic reticular cells (FRCs) form a network in the T cell zone (periarteriolar lymphoid sheath, PALS) of the WP on which T lymphocytes migrate. This network connects the PALS to the marginal zone (MZ), which is the initial site of lymphocyte entry from the blood. T cells do ...[more]

PMID: 18768849

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