Serum-mediated Depression of Neutrophil Chemiluminescence Following Blunt Trauma

Abstract
To investigate 1 possible mechanism responsible for decreased neutrophil bactericidal activity following trauma, the chemiluminescence (CL) response of normal neutrophils was measured following incubation in nonseptic and septic serum from 19 blunt trauma patients. Incubation of normal neutrophils in septic patients'' sera (61 studies) resulted in a marked decrease in the chemiluminescence response (36 .+-. 26% of control), compared to incubation in nonseptic sera (92 studies, 80 .+-. 53% of control; P < 0.005). This difference between nonseptic and septic serum was apparent immediately after injury, prior to the development of sepsis (47 .+-. 4% vs. 77 .+-. 12%; P < 0.05). The depression of the CL responses was due to a suppressive factor present in septic patients'' sera. This factor was nondialyzable and was present in high performance liquid chromatography (HPLC) fractions containing protein of MW 50 to 100,000. Removal of albumin using Affigel-blue did not remove the suppressive factor. In contrast to the suppressive effect of septic trauma serum, septic patients'' neutrophils had a normal chemiluminescence response after their isolation and washing. Trauma results in the generation of a serum factor that suppresses neutrophil chemiluminescence and that is present in greater amount in patients who eventually become septic. This factor may be responsible for the decreased bactericidal activity and depressed host defense following injury.