2009 Volume 68 Issue 1 Pages 16-20
Aim: Kampo, Sino Japanese traditional medicine has been employed for the treatment of upper respiratory infections, including influenza-like symptoms, for more than 2000 years. Interestingly, recent clinical studies have revealed the possible effectiveness of Kampo medicines to improve influenza-like symptoms. However, the mechanisms by which Kampo-medicine affects acquired immune systems against influenza infection have not been well understood. In the present study, we examined the ex vivo immune response of peripheral blood mononuclear cells (PBMCs) from healthy subjects against influenza antigens using ELISPOT assay, as well as viral replications. Materials and methods: Peripheral blood samples were obtained from 6 healthy voluneers after obtaining informed consents. PBMCs were stimulated with influenza-HA antigen for 48 hours in the presence or absence of Kakkon-to, Mao-to, Syoseiryu-to, and Keishi-toin. IFN-γ production was evaluated by ELISPOT assay. Viability of PBMCs was determined by measuring formazan formation. Viral replication was estimated with hemmaglutination assay with influenza-sensitive MDCK cells. Results: Influenza-HA antigen-specific IFN-γ production was down-regulated by treatment with Kakkon-to, Mao-to, Syoseiryu-to, and Keishi-to. Treatment with Syoseiryu-to alone inhibited cell viability. PBMCs viability was reduced by influenza-HA antigen stimulation in the presence of Kampo-medicine. The four Kampo formulae employed in the present study showed no remarkable effects on influenza virus replication in MDCK cells. Conclusion: Four Kampo-medicines that are frequently employed to treat upper respiratory infections have minimal or adverse effects on influenza-specific immune responses and viral replications. The therapeutic effects of Kampo-medicines might be with a consequence of their anti-inflammatory effects.
