Background: Hemoperfusion with PMX-F (polymyxin B covalently immobilized on fibers) has been reported to be safe and effective for patients with septic shock. However, the molecular mechanism of this usefulness is not yet clear. The purpose of this study was to evaluate whether the expression of CD14, human leukocyte antigen (HLA)-DR on monocytes, and the expression of CD16, CD11b/CD18 on neutrophils, are altered in septic patients according to the severity, and whether PMX-F treatment affects the clinical parameters and the expression of leukocyte surface antigen expression.
Patients and methods: Thirty-four patients who were taken to the National Defense Medical College hospital at emergency, and who had an identified focus of infections, were enrolled in this study. The patients were divided into three groups: non-systemic inflammatory response syndrome [SIRS]) group, sepsis group, and septic shock group. Peripheral blood samples were collected at the time of admission to our hospital. The CD14, HLA-DR expression on monocytes and the CD11b/CD18, CD16 expression on granulocytes were evaluated using flowcytometry, and the serum interleukin (IL)-6 and IL-10 levels were measured using enzyme-linked immunosorbent assay. Treatment with a PMX-F column was performed in 10 patients with septic shock.
Results: The HLA-DR expression on monocytes and the CD16 intensity on granulocytes in patients with septic shock were significantly lower than those in patients with sepsis. The serum IL-6 and 10 levels in patients with septic shock were significantly higher than those in patients with sepsis. The mean systolic blood pressure in patients with septic shock was significantly increased after the PMX-F treatment; furthermore, the HLA-DR expression on monocytes and the CD16 intensity on granulocytes were significantly increased after the PMX-F treatment. The serum IL-10 levels were significantly decreased after the PMX-F treatment.
Conclusions: We showed that the surface antigens, HLA-DR on monocytes and CD16 on granulocytes, are extremely decreased in patients with septic shock, and that PMX-F treatment is effective for beneficially increasing the surface antigen expression on leukocytes. This therapy might be a new strategy for helping patients recover from immunoparalysis in septic conditions.