Immune response induced by an HSV-1 mutant strain: a discrepancy analysis of immune system gene profile in comparison with a wild type virus strain

We previously generated an HSV-1 mutant strain, M3, which contained partial deletions in ul7, ul41 and LAT and produced an attenuated phenotype in mice. In the present study, we performed a comparative analysis to characterize the immune responses induced by M3 versus wild type HSV-1 in a mouse model. Infection with wild type HSV-1 triggered an inflammatory-dominated response and the suppression of adaptive immunity and was accompanied by severe pathological damage. In contrast, infection with M3 induced a systematic immune response involving the full activation of both innate and adaptive immunity and was accompanied by no obvious pathological changes. The mRNA expression profile in splenocytes of HSV-1 mutant strain M3 infected (3×10^4 PFU) and HSV-1 wild type strain Mckrae infected (3×10^4 PFU) BALB/c mice were measured at day 7 post-infection, and uninfected mice were used as control. The mRNA expression profile in splenocytes of HSV-1 mutant strain M3 infected (3×10^4 PFU) mice were also measured at day 30 and day 60 post-infection. Three independent experiments were performed at each time using different mice for each experiment.