FIGURE 4.

Cellular functions of human GPR84. A, chemotaxis of human peripheral PMNs. PMNs isolated from human peripheral blood were applied onto the upper chamber of a Transwell permeable support. Various concentrations of 6-OAU or 3-OH-C12 were added in the lower chambers of the Transwell. Transwell permeable supports were incubated at 37 °C for 1 h. The chemotaxis activities were assessed as a percentage of migrated cells to a lower chamber across the membrane from an upper chamber. The data were expressed as the means ± S.D. of quadruple determinations. B, chemotaxis of human GPR84 stable transfectant (CHO-GPR84). CHO-GPR84 was generated as described under “Experimental Procedures.” CHO-GPR84 cells were applied onto the upper chambers of the 96-well chemotaxis chamber. Various concentrations of 6-OAU or FFAs were added into the lower chambers. The chemotaxis activities were expressed as a migration index: (A₅₉₅ of experimental well − A₅₉₅ of background well)/(A₅₉₅ of medium control well − A₅₉₅ of background well). The data were expressed as means ± S.D.; n = 5. C, chemotaxis of U937 cell lines. U937 cells were used for the experiment after differentiation into macrophage-like cells as described under “Experimental Procedures.” Differentiated U937 cells were applied onto the upper chambers of the 96-well chemotaxis chamber. Various concentrations of 6-OAU or FFAs were added into the lower chambers. The chemotaxis activities were expressed as the same as B. The data were expressed as the means ± S.D. of triplicate determinations. *, p < 0.001 when compared with the medium control group (M). #p < 0.001 when compared with the PTX-untreated group.