The Effect Of Granulocyte Colony-Stimulating Factor (G-CSF)in Septic Mice Immune Function

Objective:The aim of this research is to through observation the change of neutrophilCD64expression、serum concentration of TNF-a and IL-10、survival rate aftertreatment with granulocyte colony stimulating factor (G-CSF),investigate the effectsof G-CSF on sepsis immune function and provide a theoretical basis for the researchof G-CSF treatment on sepsis.Methods:1、Animal:140healthy male kunming mice of10to12weeks age (18to25gweight).2、Mice model：adopt the method of intraperitoneal injection with LPS toestablish mice model of sepsis.3、Groups and treatment: mice were randomly divided into four groups, eachgroup has35mice,in group B (sepsis model group) intraperitoneal injection with10mg/kg dose of LPS; in group A (healthy control group) intraperitoneal injection withgroup B equal dose of normal saline; in group D(G-CSF treatment group)subcutaneous injection with50ug/kg dose of recombinant human granulocyte colonystimulating factor (rhG-CSF) at6h、30h after intraperitoneal injection of LPS; ingroup C(blank treatment group) subcutaneous injection with group D equal dose ofnormal saline at6h、30h after intraperitoneal injection of LPS. Randomly selected10mice in each group to observe general situation and the survival rate and drewsurvival curve; took5mice at12h,24h,36h,48h,60h after modeling from the restof35each group, collected peripheral blood of mice for detecting.4、Experimental method: used flow cytometry (FCM) to detect neutrophil CD64expression (%);used enzyme-linked immunosorbent assay (ELISA) to detect serumconcentration of TNF-a and IL-10(pg/ml).5、Statistical method: used Excel2003and SPSS18.0statistical software for dataprocessing and statistical analysis. Results:1、All mice appeared an obvious symptoms of poisoning after injected with LPS,in G-CSF treatment group mice recovered faster from symptoms of poisoning thansepsis model group and blank treatment group,1week survival rate of sepsis modelgroup and blank treatment group were50%,G-CSF treatment group was60%,survivalrate of G-CSF treatment group increased slightly compared with sepsis model groupand blank treatment group,but there was no statistically significant difference (P>0.05).2、Neutrophil CD64has a small amount of expression in healthy mice at eachpoint of time.Neutrophil CD64in sepsis model group reached peak expression(45.51±3.32%) at12h after LPS injection, significantly increased compared with thehealthy control group (2.69±1.00%)(P<0.05).Fell to (24.07±3.51%) at24h, neutrophilCD64expression at36h,48h,60h was in low level, still significantly higher thanhealthy control group(P<0.05). After treatment with G-CSF,neutrophil CD64increased significantly compared with sepsis model group and blank treatment group(P<0.05).3、Serum concentration of TNF-a in sepsis model group at12h was (203.38±15.33pg/ml), significantly increased compared to healthy control group(P<0.05),reach peak concentration (348.77±21.12pg/ml)at24h, a marked decline at48h,significantly higher than healthy control group at60h(P<0.05).After treatment withG-CSF, serum concentration of TNF-a decreased significantly at each time comparedwith sepsis model group and blank treatment group (P<0.05).4、Serum concentration of IL-10in sepsis model group at12h was (54.35±7.32pg/ml), significantly increased compared to healthy control group, reached peakconcentration(143.04±13.08pg/ml) at36h, then gradually decreased, but significantlyhigher than healthy control group at60h(P<0.05).After treatment with G-CSF, serumconcentrations of IL-10at24h、36h、48h were160.35±12.41pg/ml、177.74±13.75pg/ml、126.09±9.77pg/ml, significantly increased compared with sepsismodel group and blank treatment group (P<0.05).Serum concentrations of IL-10at12h and60h were slightly higher compared with sepsis model group and blanktreatment group, but there was no statistically significant difference (P>0.05). Conclusion:1、Neutrophil CD64has a small amount of expression in healthy mice,neutrophilCD64expression transiently increases after LPS, prompting increased neutrophilCD64expression can be used as a symbol of neutrophil activation.2、 The serum concentration of TNF-a and IL-10rise in early stage ofsepsis,which confirms the presence of proinflammatory and anti-inflammatoryreaction process during early stage of sepsis; peak concentration of IL-10appearedlater than TNF-a,prompting anti-inflammatory response may be secondary toproinflammatory reaction.3、G-CSF can promote neutrophil CD64expression in sepsis mice, promptingG-CSF can enhance neutrophil function in sepsis mice.G-CSF can reduce serumconcentration of TNF-a, increase the serum concentration of IL-10, prompting G-CSFhas anti-inflammatory effects.G-CSF can not improve the survival rate of sepsis, norincrease risk of death.