• An analysis of inhibitory anergic serum and noninhibitory control serum was done to determine the estimated molecular weights (mol wts) of the inhibitors of polymorphonuclear neutrophil (PMN) chemotaxis. Serum from reactive controls with no native inhibitors (PMN chemotaxis, 128.2 ± 4.4 μm) showed marked inhibition (PMN chemotaxis, 54.1 ± 1.3 μm) after threefold concentration through a semipermeable membrane that retained all proteins (mol wts, 30,000 daltons). Further concentration of the eluate through a membrane that retained all proteins (mol wts, >1,000 daltons) showed extreme inhibition by this fraction (PMN chemotaxis, 10.1 ± 1.2 μm). Fractionating column chromatography (Sephadex G200) of this concentrate showed most of the mol wt activity at 8,000 daltons. Sephadex G200 chromatography of 12 different inhibitory sera from anergic patients after surgery showed three peaks of PMN chemotaxis (mol wt, 400,000 daltons; mol wt, 250,000 daltons; and mol wt, 130,000 daltons). Three inhibitors with mol wts of 410,000, 38,000, and 8,000 daltons were partially purified using ammonium sulfate fractionation from the serum of a multiple-trauma victim. Fractionation of this same serum through semipermeable membranes as for normal serum again confirmed the presence of a PMN chemotaxis inhibitor (mol wt, 8,000 daltons). Ammonium sulfate fractionation of normal serum identified an inhibitor in the 8,000-dalton range. With surgical stress or major trauma, increases in the concentration of a native inhibitor (mol wt, 8,000 daltons) and possibly a "piggyback" effect on larger circulating serum proteins may lead to the detection of PMN chemotaxis inhibition in the anergic sera and the observed variability in the estimated mol wts.
(Arch Surg 1983;118:156-160)