HAMP and infection: To test if these siderophilic organisms can manipulate host iron-related proteins in the macrophage, THP-1 differentiated macrophages were infected with M. tuberculosis, M. bovis BCG, L. monocytogenes, or S. enterica, and hepcidin secretion was quantified by ELISA at the peaks of infection (24 hours for M. tuberculosis and M. bovis BCG, eight hours for L. monocytogenes and 16 hours for S. enterica).