共感染白纹伊蚊浓核病毒-3对登革2型病毒在蚊细胞内复制的影响研究

Co-infection of a mosquito- specific aedes albopictus densovirus-3 to influence dengue 2 virus replication in mosquito cell

目的研究病毒共感染白纹伊蚊C6／36细胞后，白纹伊蚊浓核病毒-3（AalDV-3）对登革2型病毒（DENV-2）在细胞内的复制的影响。方法C6／36细胞感染AaIDV-3后5d，共感染DENV-2，设立单独感染AalDV-3与DENV-2为对照组。共感染后不同时间点，qPCR法检测病毒的拷贝数；共聚焦显微镜检测DENV-2感染率；共感染后37℃孵育24h后，于1～2d以流式细胞术检测细胞凋亡率。结果共感染后不同时间点，共感染组相对于DENV-2单独感染组，DENV-2基因拷贝数均明显下降（P〈0．05），其中第8d病毒滴度降低率达到最高的67％。共感染组DENV-2细胞阳性率均低于40％，明显低于DENV-2单独感染（〉70％，P〈0．05）。流式细胞术结果显示，共感染组1～2d细胞凋亡率分别为23．43±1．02％和52．83±1．18％，明显低于DENV-2单独感染组凋亡率59．43±1．23％和96．21±1．87％（P〈0．05）。结论病毒共感染白纹伊蚊C6／36细胞后，AalDV-3可降低对DENV．2拷贝数，降低DENV-2细胞感染率，减少DENV-2诱导的细胞凋亡，AalDV-3具有防制蚊媒传染病的潜在价值。

Objective To study co-infection of a mosquito-specific Aedes albopictus densovirus-3 （AalDV-3） to interfere dengue virus type 2 （DENV-2） replication in mosquito cell. Methods Coinfected Ae. albopictus C6/36 cell with DENV-2 at 5 days post AalDV-3 infection, and DENV-2 and AalDV-3 single infected cell were used as control groups, respectively. The genome copy number of virus were quantified using real-time quantitative PCR （qPCR） , percentage of DENV-2 positive C6/36 cells were determined by confocal microscope, apoptosis ratio of infected C6/36 cell were detected using flow cytometry at different time points post infection. Results The genome copy number of DENV-2 in co- infection group was significantly lower than that of single DENV-2 infection group at different time points post infection, and reached highest inhibitory ratio （67%） at 8 days post co-infection. DENV-2 antigen positive C6/36 cells of co-infection displayed significant lower percentage （ 〉 40% ） than that of single infection group （ 〉 70% , P 〈 0.05） at different time points post infection. The apoptosis ratio of C6/36 cell in co-infection group were 23.43± 1.02% and 52.83 ±1. 18% at 1 and 2 day post infection, that were lower than that of single infection group （ 59.43± 1.23% and 96.21±1.87% , P 〈 0.05 ）. Conclusions Co-infected Aedes albopietus C6/36 cell with AalDV-3 can down regulate the gene copy number of DENV-2 in cell, infected cell ratio and apoptosis ratio, and AalDV-3 has the potential as a tool for dengue control.