MECHANISMS OF THE ADJUVANT EFFECT OF HEMOGLOBIN IN EXPERIMENTAL PERITONITIS .7. HEMOGLOBIN DOES NOT INHIBIT CLEARANCE OF ESCHERICHIA-COLI FROM THE PERITONEAL-CAVITY

Abstract

Using highly purified stroma-free hemoglobin (SFHgb), any direct effect of hemoglobin on peritoneal white blood cell function was discounted. Uncontrolled proliferation of bacteria took place in the presence of hemoglobin in the peritoneal cavity [of rats]. Nonviable 5-iododeoxyuridine 125I-labeled bacteria were then used to directly study peritoneal clearance kinetics, eliminating the problem of bacterial growth. SFHgb had no influence on the removal of i.p. bacteria. The rate of bloodstream appearance of radiolabel was similar with or without i.p. SFHgb. Thus, SFHgb does not prevent clearance of bacteria from the peritoneal cavity by interfering with normal host clearance mechanisms. SFHgb may act as a bacterial growth adjuvant, by serving as a bacterial nutrient or by suitably modifying the environement so that extensive bacterial proliferation can occur. The latter hypothesis appears to be an area in which investigation concerning the adjuvant effect of hemoglobin may prove most fruitful.