Effect of Endotoxemia and Gram-Negative Sepsis on Host Peripheral Granulocyte Endogenous Chemiluminescence

To evaluate the diagnostic potential of the chemiluminescence (CL) phenomenon for bacterial infections, polymorphonuclear chemiluminescence (PMN CL) was measured following challenge of rats with a gram-negative endotoxin-bearing microorganism, Salmonella typhimurium or Escherichia coli endotoxin. Rats inoculated with a million or a billion live or heat-killed S. typhimurium had a 6-7-fold increase in endogenous PMN CL 24 hr postinjection compared to saline controls. By 72 hr, endogenous PMN CL measured from rats injected with heat-killed S. typhimurium returned to saline control values. Endogenous PMN CL measured from rats injected with live bacteria remained significantly elevated for 7 days. A progressive 9-29-fold increase in endogenous PMN CL was also measured during the 48 hr after injection of 250 micrograms E. coli endotoxin. PMN CL response to endotoxin was linearly dose-dependent between 1.0 and 100 micrograms. Results suggest that elevated endogenous PMN CL measured following injection of the gram-negative bacteria S. typhimurium may be partially attributed to its endotoxin. Further, these data, combined with results from other studies, suggest that the elevated endogenous PMN CL response may be stimulated in part by hormonal factors, such as leukocyte endogenous mediator, released following injection of bacteria or the administration of endotoxin. (Author)