Evaluation of the efficacy of vitamin C on the immune response after rabies virus vaccine in BALB/c mice.

OBJECTIVE

Rabies is a lethal zoonotic infection caused by the rabies virus. Interferon- (INF) and interleukins (ILs) are a cytokine that is primarily produced by cells of the immune system. Vitamin C is an essential micronutrient in various biological processes, especially immune responses, and plays an essential part. Vaccination can successfully activate immune responses to virus infection protection. This study aimed to investigate the effect of vitamin C administration on immune responses to an inactivated rabies vaccine.

MATERIALS AND METHODS

Thirty male Balb/c mice weighing between 25-30 gm (8 weeks old) were used in the current experimental study and randomly equally divided into three groups. Group I: untreated healthy control group was inoculated with PBS as a negative control. Group II: vaccinated intradermally with rabies vaccine alone using a dose of 4 ml/animal at 0, 7, 21 days. Group III: In addition to the dose of vaccine, mice were injected single intraperitoneally with 10 mg of vitamin C with each dose of vaccine on days 0, 7, 21. At experimental end, serum levels of IFN-γ, IL-4, and IL-5 were measured.

RESULTS

The results revealed that vitamin C supplementation significantly elevated IFN-γ, IL-4, and IL-5 levels in vaccinated mice and treated with vitamin C (group III) compared to vaccinated group II and healthy control group I. Similarly, vitamin C supplementation exhibited strong positive correlations between IFN-γ and both IL-4 and IL-5 level in all experimental group. Taken together, these results showed that vitamin C is an important stimulator of interferon, interleukin-4 and -5 during inactivated rabies vaccine vaccination in mice.

CONCLUSIONS

Our results supported the hypothesis that indicated the immunological improvement of vitamin C to the effectiveness of the inactivated rabies virus vaccination. High dose of vitamin C increases the levels of interferon and interleukin-4 and interleukin-5.