ABSTRACT
Objective To investigate the expression and significance of major histocompatibility complex classⅡgene in multiple organ dysfunction syndrome.Methods Two-hit porcine model of MODS was duplicated in 18 swine that were randomly assigned into experimental group(Group M,n=9) and control group(Group C,n=9).The Group M was given compound factors including hemorrhagic shock,reperfusion injury and endotoxemia,and the Group C only underwent anesthesia and arterious/ve- nous eannula.After seven days,the animals were killed to remove splenic tissues fro extracting total RNA by Trizol method.The primer of SLA-DQA(MHC classⅡgene of swine)was designed to construct cD- NA by reverse transcription and the quantity of SLA-DQA mRNA detected with real time fluorescent quan- titative polymerase chain reaction(real time FQ-PCR).The standard curve was described by UVP com- puter image analysis system.Results The mortality of Group M was 78%(7/9),and the incidence rate of MODS was 89%(8/9).The expressing quantity of Group M was(1.376?1.006)?10~3,signifi- cantly lower than(5.330?3.053)?10~3 of Group C(P＜0.01).Conclusion Duplication of por- cine MODS model is satisfactory.Down-regulation of MHC classⅡgene may be due to control of classⅡtransactivator(CⅡTA)and release of multiple eytokine,such as TNF-?and IL-10.
ABSTRACT
Objective:To explore the pathogenesis of multiple organ dysfunction syndrome(MODS)with respect to the bal- ance of Th1/Th2.Methods:Eighteen healthy male minipigs,weighing 22-30 kg,were randomly divided into two groups: MODS group and control group.Double-hit method including hemorrhagic shock and endotoxiemia was used to establish the porcine MODS model.The peripheral vein blood samples were collected at different time-points(before bloodletting,before en- dotoxin injection,1 h,24 h,48 h and 72 h after endotoxin injection)in the two groups.The spleen samples were collected after death of the animals.Plasma levels of IFN-?and IL-4 were detected by enzyme-linked immunosorbent assay(ELISA).Real- time PCR was used to detect the expression of IFN-?,IL-4,T-bet and GATA-3 mRNA(The latter 2 were the key transcription factors associated with Th1/Th2 response)in the spleen samples.Results:The plasma levels of IFN-?and IL-4 quickly reached the peak values 1 h after the endotoxin injection,then the level of IFN-?decreased quickly.The ratio of IFN-?/IL-4 was signifi- cantly lower than the baseline value 72 h after endotoxin injection(P=0.000).The ratio of IFN-?/IL-4 mRNA in MODS group was obviously lower than that in the control group(P=0.020);the ratio of T-bet/GATA-3 was also lower in MODS group (P=0.038).Conclusion:The shift from Th1 to Th2 occurs in the progress of MODS.