Format

Send to

Choose Destination
See comment in PubMed Commons below
J Leukoc Biol. 2009 Mar;85(3):526-38. doi: 10.1189/jlb.0808505. Epub 2008 Dec 18.

Antigen-independent adhesion and cell spreading by inducible costimulator engagement inhibits T cell migration in a PI-3K-dependent manner.

Author information

1
Department of Pathology, Case Western Reserve University School of Medicine, 10900 Euclid Ave., Cleveland, OH 44106-4952, USA.

Abstract

Engagement of the costimulatory protein ICOS activates effector/memory T cells in tissue by enhancing TCR-mediated proliferation and cytokine production. We now report that in an antigen-independent manner, ICOS also induces adhesion and spreading in human effector/memory T cells, consequently inhibiting cell migration. T cell spreading and elongation after ICOS ligation are accompanied by the formation of two types of actin-rich membrane protrusions: thin, finger-like structures similar to filopodia and short, discrete microspikes. Although filopodia/microspike formation occurs independently of the PI-3K signaling cascade, ICOS-mediated T cell elongation depends on PI-3K activity, which inhibits the accumulation of GTP-bound RhoA. Further inhibition of RhoA activation exacerbates the ICOS-mediated, elongated phenotype. We propose that in inflamed tissue, ICOS engagement by ICOS ligand on a professional or nonprofessional APC prevents the forward motility of the T cell by inhibiting RhoA-dependent uropod retraction. The resulting ICOS-induced T cell spreading and filopodia/microspike formation may promote antigen recognition by enhancing a T cell's scanning potential of an adherent APC surface.

PMID:
19095735
PMCID:
PMC2653947
DOI:
10.1189/jlb.0808505
[Indexed for MEDLINE]
Free PMC Article
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for HighWire Icon for PubMed Central
    Loading ...
    Support Center