Recombinant human cytokines stimulate neutrophil adherence to IgG autoantibody-treated epithelial basement membranes

We investigated the ability of the purified recombinant human cytokines: tumor necrosis factor-alpha (rTNF), granulocyte-macrophage colony-stimulating factor (rGM-CSF), interleukin-1 beta (rIL-1), interleukin-3, and tumor necrosis factor-beta (rTNF-beta) to stimulate neutrophil adherence (NA) to basement membranes (BMs) of stratified squamous epithelia pretreated with autoantibodies (ABM) specific for the BM matrix protein, type-VII collagen. rTNF, rGM-CSF, rIL-1, and rTNF-beta, but not IL-3, stimulated NA and stimulation was ABM- and cytokine-concentration-dependent. Stimulation was cytokine-specific and not due to endotoxin since it was significantly inhibited by cytokine-specific antibodies but not by polymyxin B (PB). rTNF and rGM-CSF were the most potent stimulators, were effective at concentrations less than 0.067 ng/ml, and stimulated NA greater than 600%. Relative potency was: rTNF = rGM-CSF greater than rTNF-beta greater than rIL-1. Stimulation by rTNF was due to a rapid, time-dependent effect on the neutrophil, and NA appeared to be dependent, in part, on the low-affinity neutrophil receptor for IgG, Fc(gamma)RIII, because it could be specifically inhibited by monoclonal antibody (3G8) to Fc(gamma)RIII. These results suggest that rTNF, rGM-CSF, rIL-1, and rTNF-beta may contribute individually or in combination to immune-mediated inflammation and tissue injury by stimulating immune adherence of neutrophils to tissue-bound autoantibodies and immune complexes.