[Effect of bone marrow mesenchymal stem cells engraftment on secretion of inflammatory cytokine in the early stages of smoke inhalation injury in rabbits].

Objective: To explore the effect of bone marrow mesenchymal stem cells (MSCs) engraftment on secretion of tumor necrosis factor-α (TNF-α), interleukins (IL-1β, IL-6, IL-10) in peripheral blood and lung homogenates in the early stages of smoke inhalation injury.

Methods: MSCs were proliferated by the method of whole marrow culture and identified by flow cytometry. Fifty-six healthy New Zealand rabbits were randomly divided into control group (C group, n=8), smoke inhalation injury group (S group, n=24) and smoke inhalation injury+MSCs engraftment group (M group, n=24). The latter two groups were subdivided into 2, 4, 6 hours after injury subgroups, with 8 rabbits in each group. The levels of TNF-α, IL-1β, IL-6 and IL-10 in peripheral blood and lung homogenates were measured by enzyme-linked immunosorbent assay (ELISA).

Results: Compared with C group, concent of pro-inflammatory and anti-inflammatory cytokines in peripheral blood at each time point in S group were increased significantly. The concent of pro-inflammatory cytokines in lung homogenate at each time point in S group was significantly higher than those in C group, and that of anti-inflammatory cytokines showed no significant changes. Compared with the S group, concent of pro-inflammatory cytokines in peripheral blood in M group was decreased significantly, and that of anti-inflammatory cytokines was increased significantly [6 hours TNF-α (μg/L): 1.7±1.7 vs. 4.1±1.6, IL-1β (ng/L): 9.9±1.7 vs. 21.2±2.6, IL-6 (μg/L): 1.0±0.3 vs. 1.3±0.2, IL-10 (ng/L): 15.2±4.4 vs. 7.9±3.5, all P<0.05]. Concent of pro-inflammatory cytokines at each time point in M group was decreased significantly when compared with S group in lung homogenate, while only anti-inflammatory cytokine at 4 hours and 6 hours was increased significantly [6 hours TNF-α (ng/L): 503.0±156.4 vs. 587.7±171.2, IL-1β (ng/L): 0.4±0.2 vs. 0.6±0.2, IL-6 (ng/L): 155.2±13.7 vs. 350.2±20.3, IL-10 (ng/L): 23.3±5.4 vs. 11.0±5.6, all P<0.05].

Conclusion: MSCs engraftment could decrease pro-inflammatory cytokines and increase anti-inflammatory cytokines in the early stages of smoke inhalation injury, thus ameliorates inflammatory response, which confers protective effect on smoke inhalation injury.