Human recombinant tumour necrosis factor beta (rhuTNF beta)/lymphotoxin was tested for human neutrophil granulocyte (PMN), monocytes (MO), and T-cell chemotactic activity by means of a modified Boyden chamber system. Over a wide range of concentrations (10(-7)-10(-14)M)rhuTNF beta showed no chemotactic activity for PMN, MO, or T cells. In contrast, strong chemotactic migration was elicited in PMN and MO with the tripeptide N-formyl-methionyl-leucyl-phenylalanine (FMLP) and in T cells when complement split product C5a and leukotriene B4 (LTB4) were used as chemotaxins. The results of this study indicate that rhuTNF beta/lymphotoxin is not a chemotaxin for human PMN, MO, or T lymphocytes in vitro.