Blood and peritoneal neutrophil (PMN) adherence in rabbits: the effects of hemoglobin, peritoneal fluid, and infection.

Neutrophil (PMN) adherence is an important first step in PMN migration. Peritoneal fluid and hemoglobin have been implicated as inhibitors of blood PMN function. The purpose of this study was to evaluate the effects of peritoneal fluid and hemoglobin on PMN adherence in both blood and peritoneal PMNs. Adherence was measured by nylon fiber filtration. Control blood PMNs were obtained from rabbit heparinized blood. Control peritoneal PMNs were obtained by saline lavage 18 hr after the intraperitoneal instillation of hypertonic saline. Infected blood and peritoneal PMNs were similarly obtained from rabbits which had undergone appendiceal devascularization 18 hr earlier. Blood and peritoneal PMNs were tested in normal saline, serum, hemoglobin, and peritoneal fluid from infected and noninfected rabbits. Cell adhesiveness of blood and peritoneal neutrophils from infected and noninfected rabbits was similar in all groups. In normal saline and serum, cell adhesiveness was approximately 70%. In hemoglobin and peritoneal fluid, all groups of neutrophils showed a statistically significant decrease in cell adhesiveness. Based on these data we conclude: (1) Blood and peritoneal PMNs with and without infection have similar adherence. (2) Both hemoglobin and peritoneal fluid inhibit PMN adherence.