[Effect of severe thoracic trauma combined with endotoxin challenge on phagocytosis function of alveolar macrophages and pulmonary interstitial macrophages].
OBJECTIVE
To observe the difference of phagocytosis between alveolar macrophages and pulmonary interstitial macrophages, and to investigate their responses to severe thoracic trauma with or without lipopolysaccharide (LPS) challenge.


METHODS
A rat model of severe thoracic trauma was reproduced by thoracic impact machine. The alveolar macrophages and interstitial macrophages were isolated before injury and at 2, 4, 8, 16, 24 hours after injury respectively. The dynamic changes of these macrophage phagocytosis were tested by malachite green colorimetry.


RESULTS
Macrophage phagocytosis function was increased during the early stage after trauma (2 and 4 hours) and then decreased. The phagocytosis function of alveolar macrophages was stronger than that of interstitial macrophages in all time points before and after trauma. After challenge with LPS, no further significant effect on the alveolar macrophages was found, while LPS challenge could stimulate the phagocytosis of interstitial macrophages.


CONCLUSIONS
Alveolar macrophages and pulmonary interstitial macrophages are functional heterogeneous, and their response to trauma and combined with endotoxin challenge are different. The results indicate that the two subgroups of macrophages play different roles in immune function disorder after trauma.
Zhang
Wei
W
Center of Thoracic Surgery, Daping Hospital, Third Military Medical University, Chongqing 400042, China.
Jiang
Yao-guang
YG
Xie
Zhi-jian
ZJ
Hu
Cheng-xiang
CX
Li
Lei
L
D000818:Animals; D004731:Endotoxins; D008168:Lung / Q000166:cytology; D016676:Macrophages, Alveolar / Q000502:physiology*; D010587:Phagocytosis; D051381:Rats; D017208:Rats, Wistar; D017154:Stromal Cells / Q000502:physiology*; D013898:Thoracic Injuries / Q000382:microbiology*
D004731:Endotoxins