Figure 2.

Activation of LAIR-1 in human T cells. A, Hut78 cells were stimulated with anti–LAIR-1 for 24 h, and expression of LAIR-1 was examined by flow cytometry. Mean fluorescence without stimulation was 789 ± 22; mean fluorescence with an isotype control was 779 ± 28; mean fluorescence with stimulation of anti–LAIR-1 was 2115 ± 53 (p ≤ 0.01). The data shown are representative of three separate analyses. B, Jurkat cells that express human LAIR-1 were activated by αI(II) or C1q for the indicated time periods. The LAIR-1 proteins in whole-cell lysates were immunoprecipitated using protein A/G beads conjugated with anti–LAIR-1. Phosphorylation status was examined by Western blotting analysis using anti-phosphotyrosine (α-pTyr) or anti–LAIR-1 (α-hLAIR-1) antibodies. Samples primed with an irrelevant protein (OVA) did not demonstrate any phosphorylation (data not shown). The data shown are representative of three separate analyses. IB, immunoblot.