Low-dose interferon-γ influences differentiation of oligodendrocyte precursor cell through P27kip1

Abstract

Objective To expore the mechanism of low-dose interfone-γ(IFN-γ) influences on differentiation of oligodendrocyte precursor cell. Methods The cerebral cortex samples were obtained from one day old SD rats to form mixed single cell suspensions. After culturing in full medium for 7 to 10 days, succession and differential velocity adherent technique were performed to acquire oligodendrocyte precursor cell and cultured in serum-free medium. IFN-γ, AG490 and Fludarabine were added during the culture of oligodendrocyte precursor cell and reverse transcription-polymerase chain reaction, Western blot and flow cytometry were performed to evaluate the expression of intracellular P27kip1 and its influence on the differentiation of oligodendrocyte precursor cell. Results (1)The expression of P27kip1 mRNA and protein was lower in IFN-γ group than in control group (t=85. 535, P<0. 05;t= 12. 481, P<0. 05), while the expression of P27kip1 mRNA and protein in IFN-γ+AG490 group and IFN-γ+Fludarabine group were both higher than those in IFN-γ group (P<0. 05). (2) The phosphorylation levels of JAK2/STAT1 in INF-γ group were higher than that in the other three groups (P<0. 05). (3) The percentage of myelin basic protein positive cells was (68. 42 ± 2. 53)% in IFN-γ group, lower than that in control group [(88.21 ± 1.97)%](t=10.682, P < 0.05). Myelin basic protein positive cells in IFN-γ + AG490 group were (57. 63 ±2. 75) %, lower than those in the IFN-γ group. The same figure in IFN-γ+Fludarabine group were (79. 53±4. 15)% , higher than those in IFN-γ group (t = 3.957, P<0.05). Conclusions Low-dose IFN-γ can regulate the expression of intracellular P27kip1 through JAK2/STAT1 signal transduction pathway and Fludarabine may participate in this process and improve the differentiation and maturation of oligodendrocyte precursor cell. Key words: Interferon type Ⅱ; Tyrphostins; Vidarabine; Cyclin-dependent kinase inhibitor p27; Oligodendroglia; Cell differentiation