Combined Application of Xymedon Hydrochloride with Rabies Vaccine on the Background of Immunosupression

The effect of xymedon hydrochloride on the immune response of rabbits immunized with the rabies vaccine prepared from strain Shchelkovo-51 under the influence of immunosupression induced by cyclophosphamide has been studied. Xymedon hydrochloride was injected at a dose of 5 mg kg body weight in a volume of 1 cm3 twice a day in combination with the rabies vaccine. In addition, the immune response higher level of 1: 12800 was observed in the immunosupressed animals compared to 1: 6400 in the control animals immunized without the immunostimulant. At 6 months after vaccination, the antibody concentration of 1: 93.75 ± 44.68 remaining below the protective level was recorded, which indicated the weakness of the humoral link in the immune system. The counts of T- lymphocytes, B-lymphocytes, T-helpers, and T-suppressors in the blood of the immunesuppressed rabbits immunized with the rabies vaccine in combination with xymedon hydrochloride increased 3.2-fold, 1.9-fold, 7.7-fold, and 22.0-fold, respectively, when compared with the reference values. Therefore, the protective effect was followed by increasing the antigeninduced and spontaneuous lymphocyte proliferation, the numbers of T-helper cells and T lymphocytes exhibiting the cytotoxic and suppressive activity, and the virus-specific neutralizing antibody titers in cases wherein the Shchelkovo-51 vaccine in combination with xymedon hydrochloride was administered. It should be reasonable to apply the two-step rabies vaccination with the use of the immunostimulant, in particular, xymedon hydrochloride, to ensure the adequate immune response in immunodeficient animals.