P. acnes associated to antirabies vaccine is associated with increased interleukin-10 and low IL-6 concentration correlated with greater survival rates in mice infected by rabies virus

J Megid PhD^a, R Kaneno PhD^b, CN Nozaki MD^a, CJC Brito MD^a, MF Almeida PhD^c

^aSchool of Veterinary Medicine and Zootechny- Department of Veterinary Higyene and Public Health-UNESP-Botucatu-SP-Brasil, , ^bInstitute of Biological Sciences-Department of Microbiology and Immunology- UNESP-Botucatu-SP-Brasil, , ^cCenter of Zoonosis Control - São Paulo-SP-Brazil *email: jane@fmvz.unesp.br

P. acnes action was evaluated in mice infected by rabies virus and greater survival rates was observed in animals treated with the immunomodulator and antirabies vaccine. This greater survival was correlated with higher Natural Killer activity in infected mice treated using P.acnes. Considering the action of P.acnes in macrophages activity, the aim of the present trial was to evaluate macrophage activity and cytokine concentration in mice infected by rabies virus, vaccinated against it and submitted to treatment with Propionibacterium acnes (Corynebacterium parvum). This trial was conducted using 6 experimental groups submitted to rabies virus infection followed by post exposure treatment with Fuenzalida-Palacios antirabies vaccine or P. acnes or P.acnes associated to antirabies vaccine. After the treatment (24hs after infection) 15 mice were killed after 24 hs, 7d,14d and 21d. A pool of serum from 3 mice colleted at these different times was promptly submitted to cytokine assay. For the macrophage activity evaluation, peritonial macrophages were obtained by perfusion and spleen samples were colleted for adherent cells at the same time. Greater survival rate were observed in the group treated using P. acnes and anti-rabies vaccine (50%) followed by the group only treated with P. acnes (29,2%) and infected animals(25%). Higher levels of IL-10 in all moments except 24hs , IL-6 on the 7th day , and IL-4 on the 21st day were observed in the vaccinated group. Peritonial and splenic macrophage activity induced by P.acnes was verified in P.acnes control group on the 7th and at 24hs, respectively, associated to higher IL-6 levels compared to control group what suggests macrophage activity stimulation. Higher levels of IL-2 at 24hs associated to higher IL-10 and lower IL-6 levels at all times, together with the greater survival rate, were observed in the infected, vaccinated P.acnes treated group, compared to the other infected groups. The association of P.acnes to antirabies vaccine in post exposure treatment was associated to higher survival of animals suggesting the importance of immunomodulation on rabies post exposure treatment.

Paper presented at the International Symposium on Predictive Oncology and Intervention Strategies; Nice, France; February 7 - 10, 2004; in poster session 995 (Immunotherapy).