Airway epithelial cell-derived insulin-like growth factor-1 triggers skewed CD8 +T cell polarization / 中国药理学通报

ABSTRACT

Aim To investigate the effects of airway epithelial cell-derived insulin-like growth factor-1 (IGF1) on CD8 +T cell polarization. Methods Hu-man airway epithelial cell line, RPMI2650 cells, was cultured in the presence of a mice allergen, Der p1, for 72 h. IGF1 expression was checked with quantita-tive RT-PCR and Western blot. Der p1-primed RP-MI2650 cells, recombinant IGF1 and anti-IGF1 anti-body was cocultured respectively with CD8 + T cells, which were activated by anti-CD3/CD8 Ab. Apoptotic cells frequency was calculated with flow cytometry. The alteration of p53 gene hypermethylation in CD8 + T cells elicited by Der p1-primed airway epithelial cell and IGF1 was plotted. Results Both mRNA(23. 1%± 5. 2% vs 5. 2% ± 2. 3%, P < 0. 01 ) and protein (33. 4 ± 6. 4 vs 9. 2 ± 4. 6, P <0. 01 ) expression of IGF1 in RPMI2650 cells markedly increased after ex-posure to Der p1 . The increase of apoptotic CD3/CD28 Ab-activated CD8 + T cells was abolished by the pres-ence of Derp1-primed epithelial cells ( 41. 7% ± 8. 2%vs 5. 2% ± 1. 8%, P <0. 01 ) . The results were con-firmed by the addition of recombinant IGF1 . Anti-IGF1 antibody abolished the effect of the epithelial cells. Derp1-primed epithelial cells inhibited p53 gene mR-NA( 29. 1% ± 5. 9% vs 16. 2% ± 4. 3%, P <0. 01 ) and protein ( 63. 3 ± 8. 9 vs 26. 9 ± 5. 6 , P <0. 01 ) ex-pression. Anti-IGF1 antibody abolished the effect. Re-combinant IGF1 promoted CD8 + T cells′p53 gene hy-permethylation. Conclusion Der p1 induces RP-MI2650 cells to produce IGF1 , and this factor prevents CD8 + T cell apoptosis by inducing p53 gene hyperm-ethylation.