LILRA2 Selectively Modulates LPS-Mediated Cytokine Production and Inhibits Phagocytosis by Monocytes
Figure 4
Activation of monocytes via LILRA2 cross-linking significantly modulates subsequent LPS-mediated production of selected cytokines.
A. Monocytes pre-activated through LILRA2 cross-linking using anti-LILRA2 mAb for 30 min followed by 18 h stimulation with LPS produced significantly lower levels of TNFα, IL-1β and IL-12 as compared to cells treated with LPS alone (4), LPS and IgG1 (5) or LPS and anti-MHC class I mAb (6). B. Pre -activation of monocytes via LILRA2 had additive positive effect on subsequent LPS-mediated IL-10 production but did not affect IL-6 or IFNγ production. C. At 6 h time point, significant inhibition of TNFα production, modest increase in IL-10 and no change in IL-6 production was observed in response to LPS in cells cross-linked with anti-LILRA2. D. By contrast, the effects at 2 h time point were minimal for all three cytokines, although the inhibitory trend for TNFα was evident. Cytokine levels in culture supernatants were analysed by Bioplex multi-cytokine assay in quadruplicates for each experiment. Error bars represent SEM of 3 independent experiments, *p<0.05, **p<0.01, ***p<0.001.