Chemotactic inhibitors in sera of patients with neoplastic disease.

Our objective was to define the functional characteristics of chemotactic inhibitors in sera of patients with various neoplastic diseases. Fifty-nine patients were studied: lung cancer (15), breast cancer (11), lymphoma (20), leukemia (13). Chemotaxis and random motility were measured using a modified agarose technique with C5a and a bacterial filtrate of E. coli as the chemoattractants. Two types of inhibitors were found: chemotactic factor inhibitors and cell-directed inhibitors. The type of inhibitor as well as the specificity of the inhibitor for the chemoattractant (C5a or bacterial filtrate) varied depending upon the underlying neoplasm. Cell-directed inhibitors were reversible and none of the inhibitors affected random motility. Contrary to previous reports, the chemotactic factor inhibitors were heat-stable (p less than 0.001). Morphometric analysis of inhibited and non-inhibited cells using scanning electron photomicrographs showed a significant alteration in shape of the inhibited cells (p less than 0.003). The results indicate greater heterogeneity of the chemotactic inhibitors than was previously thought, as well as a tumour-dependent specificity of the inhibitors for the chemoattractants.