Echinacea purpurea Polysaccharide Reduces the Latency Rate in Herpes Simplex Virus Type-1 Infections

Objective: During the latency period of herpes simplex virus type-1 (HSV-1), the virus can occasionally reactivate, travel back to the eye and cause recurrent ocular disease. As this condition arises from the ability of HSV-1 to produce a dormant infection, effective medication to prevent the virus enter a latent state should prevent it. In this study, we applied Echinacea polysaccharide (EP) fraction as prophylactic mediator for latency prevention. Methods: In order to investigate the protective properties of EP, we evaluated its immunostimulatory functions on different immune aspects that play important roles in latency prevention (particularly IFN-gamma as one of the main indicators of cellular immunity and latency). Finally, we assessed establishment of latency by detection of thymidine kinase gene in trigeminal ganglia of BALB/c mice. Results: We demonstrated that EP promotes immune response, leading to a reduced latency rate, and it has a promising effect on latency prevention. Conclusion: EP was able to exert an antiviral action on the development of recurrent HSV-1 disease when supplied prior to infection. Copyright (C) 2009 S. Karger AG, Basel