These studies confirm that not all cells in a macrophage population express efective bactericidal functions. Two
subsets of macrophages with cell-surface markers recognized by two monoclonal antibodies, designated M43 and
1\157 were shown to be involved in the bacteicidal activity of a macrophage population. B)' indirect
radio immunoassay (RIA), it was found that these two subset markers were expressed more on the 5tu/ace of
activated manipulates than on normal cells. It seems possible that these two markers may se11Je as markers for
macrophage activation in terms of enhanced bactericidal activity
