Expression Of TNF-α MRNA In The Spleen Of Mice Induced By Candida Albicans Insoluble β-glucan

Objective Candida albicans insolubleβ-glucan (CAIBG) is a kind of biological response modifiers(BRM) which has extensive biological activities, such as increasing the number of leukocytes,anti-tumor activity,anti-virus activity and so on. Previous experiments of our research team have successfully isolated CAIBG from the cell walls of Candida albicans, and confirmed that CAIBG is able to inhibit the immuno-suppression effect of CTX in animal experiments, meanwhile CAIBG can elevate the number of leukocyte of peripheral blood in mice and can induce the introduction of TNF-αin blood, but its mechanism is not clear. In this present study, we extracted Candida albican insolubleβ-glucan from cultured Candida albicans, which has the effect on TNF-αin the spleen of mice, and we studied the mechanism of its inducing cytokines to find the relationship between cytokine and the effect of increasing peripheral leukocyte.Method Firstly we extract insolubleβ-glucan from Candida albicans. Through preliminary experiment, we investigate the climax time point and the weaken time point of TNF-αin spleen of mice after injection of CAIBG at 3 hours,6 hours,9 hours,12 hours,24 hours. 80 male kunming mice were randomly divided into four groups: normal control group,negative control group,postive control group and CAIBG group. Mice of each group except the normal control group were injected CTX intraperitoneally (100mg/kg.d^-1 for three days) to develop leucopenia model. From the fourth day of the experiment, mice of negative control group were administered sterile water intraperitoneally (0．1ml/10g), postive control group were administered rhG-CSF(30μg/kg.d^-1 ), and CAIBG group were administered CAIBG(51．2mg/kg.d^-1 ). 70g spleen of mice in each group was taken 6 hours after administration of drug at the 1day,3day,5day,7day respectively, and RNase-free Denaturing solution is put together with spleen to grind. All of the spleen samples were stored in the-70℃freezer. After experimen, expressions of TNF-αmRNA were evaluated by RT-PCR. The number of peripheral blood leukocytes of all animals were counted before experiment,1day,3day and before sacrificed; The weight of animals were measured after being killed; the index of spleen and thymus were computed and histopathology were evaluated.Results The leukocyte numbers of peripheral blood in mice were highly increased in CAIBG group compared with other three groups; The index of spleen in each groups were increased, but the index of spleen increased earlier in CAIBG group than that in postive control group, which is markedly different from the 3th day after administration of drugs(P<0．05) ; From the 5th day, there was no statistic significance between the spleen index of CAIBG group and positive control group(P>0．05) ; The index of thymus in CAIBG group were declined compared with normal control group, which were not statistically different from other three groups (P>0．05) ; The expression of TNF-αmRNA in the spleen of mice were strengthened after administration of CAIBG at 6 hours. Compared with normal control group,negative control group and positive control group, its expression in CAIBG group were obviously increased after injecting drugs at 1day,3day,5day,7day(P<0．05) ; Histopathological evaluation: we observed there was myeloid metaplasia at spleen in CAIBG group.Conclusions CAIBG can increase the level of TNF-αin blood by inducing the expression of TNF-αmRNA in the spleen of mice in transcript level and elevate the numbers of leukocytes, which may be one of the mechanism of leukocytosis induced by CAIBG. CAIBG is a kind of promising biological response modifier which is worthy of further research and development.