[Effect of CD40 knock out on cytotoxic effector function in CD8(+) T cell of mice with cigarette smoke-induced emphysema].
OBJECTIVE
To explore the effect of CD40 knock out on the cytotoxic function of CD8(+) T cell of mice with cigarette smoke-induced emphysema.


METHODS
A total of 40 male C57 mice were divided into four groups according to the random number table, including CD40(+ /+) control group, CD40(+ /+) smoke-exposure group, CD40(-/-)control group, CD40(-/-)smoke-exposure group. The smoke-exposure groups were exposed to cigarette smoke for 24 weeks to establish emphysema model. Morphological changes were evaluated by linear intercepts. The percentages of CD8, perforin, granzyme B positive cells were evaluated by immunohistochemistry. The mRNA expressions of perforin, granzyme B, interleukin (IL) -27 were measured by fluorescent real time quantitative polymerase chain reaction (RT-PCR). The IL-27 cytokine level was tested by enzyme-linked immunosorbent assay (ELISA).


RESULTS
The mean linear intercepts in CD40(+ /+) smoke-exposure group was significantly higher than CD40(+ /+) control group, CD40(-/-)control group, and CD40(-/-)smoke-exposure group [(37.2±3.6) vs (24.0±3.4), (22.5±2.4), (29.9±1.7) μm] (all P<0.05). CD40(-/-)smoke-exposure group was higher than CD40(+ /+) control group, CD40(-/-)control group (all P<0.05). The percentages of CD8 positive, perforin positive and granzyme B positive cells in CD40(+ /+) smoke-exposure group [(16.3±2.3)%, (11.4±2.1)%, (10.7±1.9)%] were significantly higher than CD40(+ /+) control group [(8.3±1.6)%, (5.1±1.2)%, (4.6±1.0)%], CD40(-/-)control group [ (6.4±1.5)%, (4.3±1.0)%, (4.2±1.0)%] and CD40(-/-)smoke-exposure group [(8.6±1.7)%, (5.6±1.3)%, (5.5±1.3)%] (all P<0.05). RT-PCR results showed that the mRNA expressions of perforin, granzyme B and IL-27 in CD40(+ /+) smoke-exposure group [(20.3±7.3), (18.3±12.3), (2.2±0.7)] were significantly higher than CD40(+ /+) control group [(9.4±4.8), (10.6±3.8), (1.3±0.6)], CD40(-/-)control group [ (8.1±3.1), (7.7±3.5), (1.1±0.5)] and CD40(-/-)smoke-exposure group [(12.9±6.2), (10.4±4.6), (1.5±0.4)] (all P<0.05). ELISA results showed that the level of IL-27 in CD40(+ /+) smoke-exposure group was significantly higher than CD40(+ /+) control group, CD40(-/-)control group and CD40(-/-)smoke-exposure group [(3 242±754) vs (1 627±710), (1 600±680), (1 850±583) ng/L] (all P<0.05).


CONCLUSIONS
Knockout the CD40 gene can inhibit the cytotoxic effector function in CD8(+) T cells of mice with cigarette smoke-induced emphysema, and alleviate the degree of emphysema.
Department of Respiratory Diseases, First Affiliated Hospital, Guangxi Medical University, Nanning 530021, China.
Q
Q
Wang
T T
TT
Deng
L J
LJ
Kuang
S L
SL
Qiu
Y
Y
Liang
X N
XN
Zhong
Z Y
ZY
He
J Q
JQ
Zhang
J
J
Bai
M H
MH
Li
D000818:Animals; D019013:CD40 Antigens; D018414:CD8-Positive T-Lymphocytes / Q000378:metabolism*; D016207:Cytokines; D004195:Disease Models, Animal; D004646:Emphysema; D004797:Enzyme-Linked Immunosorbent Assay; D053804:Granzymes; D007378:Interleukins; D008168:Lung / Q000503:physiopathology; D008297:Male; D051379:Mice; D018345:Mice, Knockout; D011656:Pulmonary Emphysema / Q000139:chemically induced / Q000378:metabolism*; D012333:RNA, Messenger; D012906:Smoke / Q000009:adverse effects*; D012907:Smoking / Q000009:adverse effects*; D014026:Nicotiana
D019013:CD40 Antigens; D016207:Cytokines; D007378:Interleukins; C464565:MYDGF protein, human; D012333:RNA, Messenger; D012906:Smoke; C509213:GZMB protein, human; D053804:Granzymes