Epidermal growth factor receptor-containing exosomes induce tumor-specific regulatory T cells / 中国药理学通报

ABSTRACT

Aim Toinvestigatewhetherepidermal growth factor receptor ( EGFR )-containing exosomes could induce tumor-specific regulatory T cells, and the effects of those T cells on tumor protein-specific CD8+Tcells.Methods TheexosomeswithEGFRwerepu-rified from NSCLC tumor, which modulated tolerogenic property of DCs. Then the induced TolDCs generated tumor-specific Tregs, with which the tumor protein-specific CD8 + T cells were suppressed. Results 80%exosomeswereEGFRpositivefromLCpatients while less than 2% exosomes were EGFR positive from control lung tissue. After exposed to the exosomes in the culture for 7 days, the IDO+ DCs proportion was much higher than that in control group ( 80. 8% ± 3. 2% vs 65. 6% ± 6. 4%, P <0. 05 ) . The induced Tregs was also higher ( 24. 1% ± 5. 2% vs 4. 2% ± 2. 3%,P<0. 01 ) , which suppressed the proliferation of CD8+ T cells(5. 4% ± 0. 2% vs 86. 7% ± 9. 3%, P<0.01).Conclusion Thepurifiedexosomesin-duce tolerogenic DCs. Coculture of the tolerogenic DCs and Th0 cells generates the tumor antigen-specific reg-ulatory T cells. The Tregs could suppress the tumor an-tigen specific CD8+ T cells.