Danger patterns and pattern recognition receptors have been targets in the investigation and treatment of systemic inflammatory response syndrome and sepsis. Lipopolysaccharide (LPS)-binding protein (LBP) presents LPS and gram-positive bacterial cell wall products to the receptors TLR4/MD-2 and TLR2, respectively. Low concentrations of LBP stimulate responses to LPS and peptidoglycan, whereas higher concentrations inhibit these responses. Soluble CD14 (sCD14) presents the LBP-LPS complex to CD14-negative cells, and it modulates the biological activity of circulating LPS. In this study, we aimed to elucidate the physiological reactions to LBP and sCD14 after total hip replacement surgery during spinal/epidural anaesthesia.
Seven patients with coxarthrosis were operated upon with a total hip replacement, which is a defined trauma to bone and muscles in conjunction with a certain amount of blood loss. Venous blood samples were taken before the operation and at 1 h, 3 days and 6 days after surgery. LBP and sCD14 were measured by conventional ELISA. To correct for hemodilution, each parameter was adjusted for hematocrit. A panel of cytokines was measured using Luminex technology to evaluate the trauma reaction.
IL-6 levels peaked 24 h after the operation, whereas IL-1β and IL-10 levels remained unchanged. Systemic levels of LBP were increased 24 h after surgery, whereas sCD14 remained steady. However, the dilution-corrected sCD14 values increased significantly, and the levels of both LBP and sCD14 peaked at day 3 after surgery.
Aseptic trauma primes the innate immune system for the posttraumatic release of LBP and sCD14.