MAPKAPK3 and infection: In NHBE and THP-1 cells, five mitogen-activated protein kinase (MAPK) family members (MAP2K3, MAP2K6, MAPKAPK2, MAPKAPK3, MAPKAPK5) showed decreased activity or no significant change during pH1N1 infection, and increased activity during H3N2 and H5N1 infection (Fig. 3F).