This study aims to compare the different latent infections of herpes simplex virus type I in a murine model. One hundred and twenty BALB/c mice were randomly assigned into either of three groups: intravenous inoculation group, ocular abrasion group, and intranasal inoculation group. Six weeks later, the trigeminal ganglia (TG) were removed to detect the expression of HSV-I antigen. HSV DNA in TG was also detected by polymerase chain reaction to confirm latent infection. The rate of HSV DNA in TG detected in the intravenous inoculation group was 18/22 and 22/26 in the ocular abrasion group, both of which were higher than the rate detected in the intranasal inoculation group (18/30). The expression of HSV antigen in TG in these three groups was all negative. Mortality rate in the intravenous inoculation group was 8/30, which was much higher than those of the two other groups. Intranasal virus dripping, cornea abrasion, and intravenous injection can detect latent HSV-I infection in a murine model. Compared to two other groups, the cornea abrasion group showed less severe signs, a quicker recovery rate in acute infection, and higher incidence rate of latent infection. Therefore, it is an ideal method in the presence of latent HSV-I infection.

Objective To construct a recombinant adenovirus vector for expression of proline-arginine rich 39-amino acid peptide(PR-39).Methods PR-39 gene was amplified from the plasmid containing core encoding region of PR-39 and subcloned to shuttle plasmid pAdTrace-TO4.The constructed recombinant shuttle plasmid was linearized with PmeⅠ and transfected to competent AdEasier cells.The obtained recombinant adenovirus plasmid pAdPR-39 was transfected to HEK293 cells for packaging of recombinant adenovirus which was then propagated and determined for titer.Murine fetal mesenchymal stem cells C3H10T1/2 were infected with recombinant adenovirus AdPR-39,observed for expression of red fluorescent protein(RFP) by fluorescent microscopy,and determined for transcription level of PR-39 gene by RT-PCR. Results Restriction analysis with KpnⅠ and Hind Ⅲ and sequencing proved that recombinant adenovirus shuttle plasmid pAdTrace-TO4-PR-39 was constructed correctly.Digestion of pAdPR-39 with PacⅠ proved that the target gene was integrated into the genome of adenovirus.The titer of AdPR-39 of passage 4 was l0 10 IU/ml.RFP was expressed in C3H10T1/2 cells infected with AdPR-39.PR-39 gne was successfully transcribed in C3H10T1/2 cells.Conclusion Recombinant adenovirus vector for expression of PR-39,containing RFP reporter gene,was successfully constructed and highly expressed in murine fetal mesenchymal stem cells C3H10T1/2.

Herpes simplex virus (HSV) is one of the most common viruses infecting humans and animals. Cellular adhesion is increased in HSV and plays a role in pathogenesis of inflammatory response during this viral infection. In our study, we studied a potential role of glycyrrhizin in disrupting cellular adhesion in HSV. We isolated rat cerebral capillary vessel endothelial cells (CCECs) and polymorphonuclear leukocytes (PMN) and evaluated intercellular adhesion between these cells by micropipette aspiration technique. The adhesion force and stress between CCEC and PMN were significantly (P < 0.01) increased in HSV infection. Glycyrrhizin perfusion significantly (P < 0.01) reduced adhesion force and stress between CCEC and PMN. In conclusion, glycyrrhizin may attenuate inflammatory responses in HSV by inhibition of adhesion between CCEC and PMN.

This study shows that the influence of different stress factors impacts the reactivation of latent herpes simplex virus type 1 (HSV-1) specifically in the trigeminal ganglion of infected mice. Different stress factors including hyperthermia, hypothermia, fatigue, and immunosuppression were exerted on mice infected with HSV-1. These viral antigens were then detected in the trigeminal ganglion region of infected mice under the influence of each stress factor, with hyperthermia having the most influence on reactivation. Interestingly, an increase in IL-6 was also detected in mice subjected to hyperthermia. These studies therefore suggest that stress can induce the reactivation of latent HSV-1, possibly through the induction of IL-6, in the trigeminal ganglion region of infected mice. This reveals a new insight on the pathogenesis of relapse infection of HSV-1.