Alterations in Leukocyte Function following Surgical Trauma: Differentiation of Distinct Reaction Types and Association with Tumor Necrosis Factor Gene Polymorphisms

Endotoxin-stimulated blood cytokine responses have been widely used to describe compromised host defense mechanisms after trauma. We investigated whether blood cytokine production after endotoxin stimulation is able to define distinct trauma-induced alteration patterns and whether alteration patterns are associated with tumor necrosis factor (TNF) gene polymorphisms. In 48 patients undergoing joint replacement, the levels of TNF alpha (TNF-α), interleukin 6 (IL-6), and IL-8 production in blood after endotoxin stimulation were measured preoperatively on the day of surgery and 24 h thereafter. Patients were genotyped for the TNF-α position −308 G/A polymorphism and the TNF-β NcoI polymorphism. Postoperative alterations, i.e., increases or decreases of cytokine levels (TNF-α versus IL-6, P = 0.013; TNF-α versus IL-8, P = 0.001; IL-6 versus IL-8, P = 0.007), and relative postoperative changes, i.e., percentages of preoperative cytokine levels (TNF-α versus IL-6, r(s) = 0.491, P < 0.001; TNF-α versus IL-8, r(s) = 0.591, P < 0.001; IL-6 versus IL-8, r(s) = 0.474, P < 0.001 [where r(s) is the Spearman rank correlation coefficient]), had significant positive correlations among the cytokines. Overall enhanced postoperative alteration patterns were found in 10 patients, attenuated patterns were found in 18 patients, and mixed patterns were found in 20 patients. Preoperative cytokine production levels differed significantly between these groups (those of the overall enhanced pattern group were less than those of the mixed pattern group, which were less than those of the overall attenuated pattern group). TNF polymorphisms were not associated with overall alteration patterns, but the A*TNFB1 haplotype was associated with a postoperative increase in TNF-α production (P = 0.042). Whole-blood cytokine responses to endotoxin define the following preexisting patterns in leukocyte function: low baseline production and overall enhanced alteration patterns after trauma (type 1), intermediate baseline production and mixed alteration patterns (type 2), and high baseline production and overall attenuated alteration patterns (type 3). TNF gene polymorphisms were associated with changes in TNF-α production but do not explain the overall reaction patterns of cytokine production after trauma. The clinical correlate of these newly defined reaction types remains to be determined

Ubiquitin immunoreactivity in cerebrospinal fluid after traumatic brain injury: Clinical and experimental findings

OBJECTIVE:Recent data indicate that ubiquitin is increased in serum after trauma and might regulate immune functions. Its cellular source is unknown. Because there have been no previous studies after traumatic brain injury (TBI), we determined whether ubiquitin immunoreactivity is increased in cerebrospinal fluid (CSF) after TBI. DESIGN AND SETTING:Prospective observational study of patients, with a subsequent interventional study of animals. SUBJECTS:The subjects were 14 patients with TBI, five patients with nontraumatic subarachnoid hemorrhage, ten nonneurologic controls, and seven cross-bred swine. INTERVENTIONS:Standardized TBI. MEASUREMENTS AND MAIN RESULTS:Ubiquitin immunoreactivity was analyzed by enzyme-linked immunosorbent assay and immunoblotting. Hemolysis was assessed spectrophotometrically. CSF ubiquitin levels (mean ± sd) were 19 ± 3 ng/mL in nonneurologic control patients, 81 ± 48 ng/mL at 7 ± 2 hrs after TBI (p = .002), and at the end of operation in patients with nontraumatic subarachnoid hemorrhage they were 104 ± 68 ng/mL (p = .001). CSF and serum ubiquitin were measured for 7 days in six patients with TBI. In survivors (n = 3), CSF ubiquitin levels progressively recovered, whereas in nonsurvivors (n = 3), the levels increased until death. There was no difference in serum ubiquitin levels between survivors/nonsurvivors and there was no correlation between serum and CSF ubiquitin levels. In swine, CSF ubiquitin levels peaked at 8- to 30-fold higher than baseline at 60 min post-TBI and then declined with a half-life of 1.3 hrs. In CSF with hemolysis, peak ubiquitin levels were five-fold higher than without hemolysis (p < .05). Ubiquitin and hemoglobin correlations in CSF and after in vitro lysis of erythrocytes suggested that erythrolysis could account for no more than 23 ± 16% of the CSF ubiquitin. CONCLUSIONS:CSF ubiquitin levels are increased more than four-fold in patients after TBI and nontraumatic subarachnoid hemorrhage. Peak CSF ubiquitin measurements in patients with TBI probably underestimated the actual peak, on the basis of data from the animal model. The progressive rise in CSF ubiquitin in patients with TBI who died suggests that lack of clearance could reflect lethal progression to irreversible brain damage. Erythrolysis is one potential source of CSF ubiquitin