Abstract
Chinese herbs Radix Isatidis and Viola yedoensis Makino have been implicated to possess antiviral activity. This study is to test whether these herbs are capable of modulating the immune function in Balb/cByJ mouse that supports such activity. We first confirmed that the extract from Viola yedoensis Makino, but not Radix Isatidis or a homeopathic medicinal drink Método Canova, could inhibit the replication of HSV-1 and enterovirus 71 in human neuroblastoma SK-N-SH cell line. Subsequently, the herbal extracts and Método Canova were subjected to the immunomodulatory tests with 120 6-8 weeks old mice. The animals were randomly divided into to 8 groups, of which 6 groups were fed with the half human-to-mouse-body-weight-adjusted doses of the herbal medicine and Método Canova for 9 weeks. At 8th week, these 6 groups and an unfed group of mice were injected peritoneally with one dose of the immune suppressant 5'-fluorouracil, and all 8 groups of animals were sacrificed a week later for immune function evaluations, which included the measurements of the WBC counts and the IgG levels, the numbers for B-, T-, and I-A/I-E-splenocytes, the proliferative rates for B- and T-splenocytes upon stimulation, and the serum cytokine and chemokine levels with protein arrays. Among the tests, we detected that serum BLC and MIP-2 levels were dramatically increased in mice fed with Radix Isatidis. This result indicates that taking the herb extract can improve the responsiveness of immune cells to inflammation, as these two chemokines possess the capability of inducing neutrophils, macrophages, and B-cells chemotaxis. However, no mouse in any group showed a clear improvement in cellular immunity that can suppress viral infections.
