[Expression of tumor necrosis factor-alpha and caspase-3 protein in monocytes adjacent to the invaded Echinococcus multilocularis in liver].
OBJECTIVE
To investigate the expression and its significance of tumor necrosis factor-alpha (TNF-alpha) and caspase-3 protein in monocytes adjacent to the invaded Echinococcus multilocularis in liver.


METHODS
40 female Kunming mice were randomly divided into experimental group (n=20) and sham operation (control) group (n=20). Mice in experimental group were infected with 20% E. multilocularis suspension (0.1 ml per mouse) through abdominal opening injection in liver and the mice in control group were injected with equal physiological saline. The mice were sacrificed at 6 months post-infection for observing the growth and metastasis of E. multilocularis. Pathological changes were observed by HE staining. The expression of TNF-alpha and caspase-3 protein in hydatid cyst and metastasis tissue were detected by immunohistochemistry staining and the apoptosis of the monocytes was measured by TUNEL.


RESULTS
After 6 months post-infection, E. multilocularis were spread over the liver of the mice in experimental group. Metastasis rate of lymph nodes was 45.0% (9/20). Infiltration of monocytes was observed around E. multilocularis in liver and lymph nodes with metastasis by HE staining. Immunohistochemistry showed that the positive expression rate of TNF-alpha and caspase-3 protein in monocytes was 100% and 100%, and 95% and 100% respectively around the cyst in experimental group, while the expression rate was only 5% and 0 respectively in the liver of the control mice (P<0.01). The monocytes showed significant apoptosis by TUNEL in experimental group with a positive expression rate of 100%, with a significant difference between experiment group and the control (P<0.01).


CONCLUSIONS
In the process of alveolar Echinococcus infection, the high expression of TNF-alpha protein might be associated with the apoptosis of monocytes, which may inhibit the host immunological function.
Department of Hepatobiliary Surgery, the First Affiliated Hospital, Medical College of Shihezi University, Shihezi 832002, China.
Hong-Qiang
HQ
Yang
Shao-Bo
SB
Ma
Zhi-Yuan
ZY
Bian
Jiang
J
Li
Hong
H
Zou
Shi-Jie
SJ
Zhang
Xin-Yu
XY
Peng
Xiao-Ping
XP
Chen
D000818:Animals; D017209:Apoptosis; D053148:Caspase 3 / Q000378:metabolism*; D004444:Echinococcosis, Hepatic / Q000378:metabolism / Q000469:parasitology / Q000473:pathology*; D048210:Echinococcus multilocularis; D005260:Female; D008099:Liver / Q000469:parasitology / Q000473:pathology; D051379:Mice; D008815:Mice, Inbred Strains; D009000:Monocytes / Q000166:cytology / Q000378:metabolism*; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism*
D014409:Tumor Necrosis Factor-alpha; C505409:Casp3 protein, mouse; D053148:Caspase 3