Abstract:
Following acute herpes simplex virus type 2 (HSV-2) infection, the virus undergoes an asymptomatic latent infection of sensory neurons of dorsal root ganglia (DRG). Chemical and physical stress cause intermittent virus reactivation from latently infected DRG and recurrent virus shedding in the genital mucosal epithelium causing genital herpes in symptomatic patients. While T cells appear to play a role in controlling virus reactivation from DRG and reducing the severity of recurrent genital herpes, the mechanisms for recruiting these T cells into DRG and the vaginal mucosa (VM) remain to be fully elucidated. The present study investigates the effect of CXCL9, CXCL10, and CXCL11 T-cell-attracting chemokines on the frequency and function of DRG- and VM-resident CD4+ and CD8+ T cells and its effect on the frequency and severity of recurrent genital herpes in the recurrent herpes guinea pig model. HSV-2 latent-infected guinea pigs were immunized intramuscularly with the HSV-2 ribonucleotide reductase 2 (RR2) protein (Prime) and subsequently treated intravaginally with the neurotropic adeno-associated virus type 8 expressing CXCL9, CXCL10, or CXCL11 chemokines to recruit CD4+ and CD8+ T cells into the infected DRG and VM (Pull). Compared to the RR2 therapeutic vaccine alone, the RR2/CXCL11 prime/pull therapeutic vaccine significantly increased the frequencies of functional tissue-resident and effector memory CD4+ and CD8+ T cells in both DRG and VM tissues. This was associated with less virus in the healed genital mucosal epithelium and reduced frequency and severity of recurrent genital herpes. These findings confirm the role of local DRG- and VM-resident CD4+ and CD8+ T cells in reducing virus shedding at the vaginal site of infection and the severity of recurrent genital herpes and propose the novel prime-pull vaccine strategy to protect against recurrent genital herpes.IMPORTANCEThe present study investigates the novel prime/pull therapeutic vaccine strategy to protect against recurrent genital herpes using the latently infected guinea pig model. In this study, we used the strategy that involves immunization of herpes simplex virus type 2-infected guinea pigs using a recombinantly expressed herpes tegument protein-ribonucleotide reductase 2 (RR2; prime), followed by intravaginal treatment with the neurotropic adeno-associated virus type 8 expressing CXCL9, CXCL10, or CXCL11 T-cell-attracting chemokines to recruit T cells into the infected dorsal root ganglia (DRG) and vaginal mucosa (VM) (pull). We show that the RR2/CXCL11 prime-pull therapeutic vaccine strategy elicited a significant reduction in virus shedding in the vaginal mucosa and decreased the severity and frequency of recurrent genital herpes. This protection was associated with increased frequencies of functional tissue-resident (TRM cells) and effector (TEM cells) memory CD4+ and CD8+ T cells infiltrating latently infected DRG tissues and the healed regions of the vaginal mucosa. These findings shed light on the role of tissue-resident and effector memory CD4+ and CD8+ T cells in DRG tissues and the VM in protection against recurrent genital herpes and propose the prime-pull therapeutic vaccine strategy in combating genital herpes.
摘要:
急性单纯疱疹病毒2型(HSV-2)感染后,该病毒经历了无症状的背根神经节(DRG)感觉神经元的潜伏感染。化学和物理压力会导致潜伏感染的DRG间歇性病毒重新激活,并在生殖器粘膜上皮中反复出现病毒脱落,从而在有症状的患者中引起生殖器疱疹。虽然T细胞似乎在控制DRG的病毒再激活和降低复发性生殖器疱疹的严重程度方面发挥作用,募集这些T细胞进入DRG和阴道粘膜(VM)的机制仍有待完全阐明.本研究探讨了CXCL9、CXCL10和CXCL11T细胞吸引趋化因子对DRG-和VM-常驻CD4+和CD8+T细胞频率和功能的影响及其对复发性生殖器疱疹频率和严重程度的影响。用HSV-2核糖核苷酸还原酶2(RR2)蛋白(Prime)对HSV-2潜伏感染的豚鼠进行肌内免疫,然后用表达CXCL9,CXCL10或CXCL11趋化因子的8型神经腺相关病毒进行阴道内处理,以招募CD4和CD8T细胞进入感染的DRG和VM(Pull)。与单独的RR2治疗性疫苗相比,RR2/CXCL11prime/pull治疗性疫苗显著增加了DRG和VM组织中功能性组织驻留和效应记忆CD4+和CD8+T细胞的频率.这与愈合的生殖器粘膜上皮中的病毒减少以及复发性生殖器疱疹的频率和严重程度降低有关。这些发现证实了局部DRG和VM驻留的CD4和CD8T细胞在减少感染部位的病毒脱落和复发性生殖器疱疹的严重程度中的作用,并提出了新型的初免疫苗策略来预防复发性生殖器疱疹。重要意义本研究使用潜伏感染的豚鼠模型研究了新型的prime/pull治疗性疫苗策略,以预防复发性生殖器疱疹。在这项研究中,我们使用的策略涉及使用重组表达的疱疹病毒蛋白-核糖核苷酸还原酶2(RR2;prime)免疫2型感染单纯疱疹病毒的豚鼠,然后用表达CXCL9,CXCL10或CXCL11T细胞吸引趋化因子的8型腺相关病毒进行阴道内治疗,将T细胞募集到受感染的背根神经节(DRG)和阴道粘膜(VM)中(牵拉).我们表明,RR2/CXCL11引发治疗性疫苗策略导致阴道粘膜中病毒脱落的显着减少,并降低了复发性生殖器疱疹的严重程度和频率。这种保护与浸润潜伏感染的DRG组织和阴道粘膜愈合区域的功能性组织驻留(TRM细胞)和效应(TEM细胞)记忆CD4和CD8T细胞的频率增加有关。这些发现揭示了组织驻留和效应记忆CD4+和CD8+T细胞在DRG组织中的作用以及VM在预防复发性生殖器疱疹中的作用,并提出了对抗生殖器疱疹的初免治疗性疫苗策略。