| First Author | Suzuki J | Year | 2007 |
| Journal | Blood | Volume | 109 |
| Issue | 1 | Pages | 168-75 |
| PubMed ID | 16973965 | Mgi Jnum | J:142177 |
| Mgi Id | MGI:3820496 | Doi | 10.1182/blood-2005-12-020164 |
| Citation | Suzuki J, et al. (2007) The actin cloud induced by LFA-1-mediated outside-in signals lowers the threshold for T-cell activation. Blood 109(1):168-75 |
| abstractText | The dynamic rearrangement of the actin cytoskeleton plays critical roles in T-cell receptor (TCR) signaling and immunological synapse (IS) formation in T cells. Following actin rearrangement in T cells upon TCR stimulation, we found a unique ring-shaped reorganization of actin called the 'actin cloud,' which was specifically induced by outside-in signals through lymphocyte function-associated antigen-1 (LFA-1) engagement. In T-cell-antigen-presenting cell (APC) interactions, the actin cloud is generated in the absence of antigen and localized at the center of the T-cell-APC interface, where it accumulates LFA-1 and tyrosine-phosphorylated proteins. The LFA-1-induced actin cloud formation involves ADAP (adhesion- and degranulation-promoting adaptor protein) phosphorylation, LFA-1/ADAP assembly, and c-Jun N-terminal kinase (JNK) activation, and occurs independent of TCR and its proximal signaling. The formation of the actin cloud lowers the threshold for subsequent T-cell activation. Thus, the actin cloud induced by LFA-1 engagement may serve as a possible platform for LFA-1-mediated costimulatory function for T-cell activation. |
