ABSTRACT
Objective To explore the role of Toll-like receptor 7 (TLR7) and related signal transduction molecules in mechanisms underlying human papilloma virus (HPV) infection and condyloma acuminatum (CA) recurrence.Methods Peripheral blood was obtained from 30 healthy controls,35 patients with primary CA,32 patiens with recurrent CA and 30 patients with recurrent CA treated by imiquimod and ALA-PDT.Two-color flow cytometric analysis was used to detect TLR7 expression in different peripheral blood T cell subsets,Western blot to determine the expression levels of an adapter protein myeloid differentiation primary response gene 88 (MyD88),and signaling molecules including tumor necrosis factor receptor-associated factor (TRAF6),phosphatidylinositol3-kinase (PI3K),protein kinase B (AKT),p42/44 and nuclear factor-kappa B (NF-κB) in peripheral blood CD3+ T cells,from these subjects.Statistical analysis was carried out by Student's t test using the software SPSS 13.0.Results TLR7 was expressed in peripheral blood CD3+CD4+ T cells and CD3+CD8+ T cells from the healthy controls.Compared with the healthy controls,the patients with primary and recurrent CA showed no significant changes in TLR7 expression in CD3+CD8+ T cells,but a statistical increase in TLR7 expression in CD3+CD4+ T cells (23.3％ ± 8.4％ and 32.8％ ± 8.9％ vs.12.6％ ± 6.3％,t =4.72,10.76,both P ＜ 0.01).Decreased expression of TLR7 in CD3+CD4+ T cells was observed in patients treated with imiquimod and ALAPDT compared with the patients with recurrent CA (20.3％ ± 5.7％ vs.32.8％ ±8.9％,t =5.41,P ＜ 0.01).The protein expressions of MyD88,TRAF6,PI3K,p42/44 and NF-κB were significantly increased in CD3 + T cells,while the AKT protein expression experienced no significant changes in patients with primary or recurrent CA compared with the healthy controls.A significant decrease was observed in the protein expression of MyD88,TRAF6,p42/44 and NF-κB in the treated patients compared with those with recurrent CA.Conclusions TLR7,which is highly expressed in peripheral blood CD3+CD4+ T cells in patients with CA,may take part in the host immune response against HPV and serve as a recognition receptor for HPV infection.