[Study on the relationship between the human leucocyte antigen-DR expression on CD14+ monocytes and sepsis]

To investigate the changes in the expression of HLA-DR on CD14+ monocytes of burn patients with delayed resuscitation, and to analyze the relationship between it and sepsis.

Twenty-five patients with total burn surface area over 30% TBSA and delayed resuscitation were enrolled in the study, among which 7 were complicated by sepsis during hospitalization. Peripheral blood was collected on 1, 3, 7, 14 and 28 post-burn days (PBD), and the blood of the patients with sepsis were also collected on the 1 and 2 days after the occurrence of sepsis. Twenty healthy volunteers were enrolled as controls. Expression rate of HLA-DR on CD14+ monocytes was determined by flow cytometry. The level of TNF-alpha and IL-10 were measured by ELISA.

Expression rate of HLA-DR antigen on CD14+ monocytes in burn patients without sepsis on 1, 3, 7, 14, 28 PBD were (15 +/- 6)%, (7 +/- 5)%, (26 +/- 17)%, (28 +/- 16)% and (47 +/- 16)%, respectively, which were obviously lower than that of healthy people [(92 +/- 10)%, P < 0.01], and it was also markedly lower on 1 and 2 days after the occurrence of sepsis than that of controls and those of patients without sepsis on 1, 7, 14, 28 PBD (P < 0.01). The positive rate and concentration of TNF-alpha in patients with sepsis were obviously higher than that of healthy people and patients without sepsis (P < 0.05 or P < 0.01). There was a negative correlation between the expression rate of HLA-DR on CD14+ monocytes and IL-10 levels, and it showed significant difference on 1, 7, and 28 PBD (r = -0.9963, -0.7459, -0.8474, respectively, P < 0.01).

Immune function is suppressed and proinflammatory mediators are excessively released in severely burn patients after delayed resuscitation, especially when complicated with sepsis. Expression of HLA-DR on CD14+ monocytes may be an useful parameter for monitoring the immune function of burn patients.