Modulation And Effect Of Recombinant Human Phospholipase D2 On The Expressions Of IL-1βand TNF-α In Activated Microglia And Asthmatic Relevant Factors In Guinea-pigs Attacked By Asthma

Objective: The present study was to investigate the modulation of recombinant human phospholipase D2(rhPLD2) on the expressions of IL-lp and TNF-a in a murine microglia cell line N9 stimulated by bacterial endotoxin and the effect on the expressions of some relevant inflammatory factors of guinea-pigs attacked by chronic asthma, respectively.Methods: (1)Groups of log-phase N9 cells were cultured for 24h in the presence of LPS or rhPLD2, respectively. Culture cells were harvested at four different time points of incubation for the detections of cytokine mRNA expressions by RT-PCR and culture supernatants were assayed for IL-l and TNF-a by ELISA. (2) Using different concentrations of rhPLD2 to interfere with guinea-pigs attacked by chronic asthma, after three times of doing it, anminals were bleeded to count eosinophil cells and to detect platelet activating factor(PAF). Then, after animals were sacrificed, their lungs were detached for the detection of IL-5 mRNA by RT-PCR, and bronchial aveolar lavage(BALF) were sampled to count eosinophil cells and to measure metalloproteinase-9(MMP-9) by means of ELISA.Results: (1) Recombinant human phospholipase D2 can suppress the expressions of IL-l and TNF-a(both detected by RT-PCR and ELISA) of N9 stimulated by LPS. (2) Using rhPLD2 on guinea-pigs affected by chronic asthma has a capability to relieve the increases of the quantity of Eos(both in blood and BALF), PAF in blood, the expressions of hematic IL-5 and MMP-9 in BALF.Conclusions: These findings suggested that rhPLD2 can suppress the expressions of IL-l and TNF in activated microglia and decrease the relevant inflammatory factors in guinea- pigs attacked by asthma.