Vaccination is the best biomedical approach to preventing from diseases. Proteins and peptides purified from microorganisms or synthesized chemically are weakly antigenic and need adjuvant to provide strong immune responses. Many substances with adjuvant properties have been discovered in different laboratories all over the world. However, only aluminum compounds continues to be traditional in clinical use. Although aluminum is regarded as safe, it has caused different effects, such as eosinophilia, abscesses, myofascilitis, granuloma formation and allergy, and influenced on the incidence of Alzheimer’s disease. To avoid possible side effects of aluminum and to achieve long lasting immune responses, intensive research on development of new adjuvants has been conducted.
Cross-linked anionic polyelectrolyte hydrogels (PHG) have been synthesized via dispersion polymerization in non-polar organic media and their structures, functionality, hydrodynamic diameters have been determined. Newly synthesized polymers MG-4 and MG-8 are the same in terms of quality chemical composition, but differ in quantitative ratios of monomer units. Aim of the study has been to evaluate immunological possibilities of PHG and its biological influence on mice. The adjuvant properties of PHG have been investigated using a model protein - bovine serum albumin (BSA). Mice 5 month old have been injected subcutaneously with PHG (MG-4 or MG-8) and BSA together, and with BSA alone, and with 0.9 % isotonic NaCl solution. Immunization has been performed on the following days: 1, 14 and 28. One week after the last injection antibodies have been isolated. The anti-BSA antibodies titers have been measured by immunoassay analysis. Possibilities of PHG MG-4 and MG-8 to produce of anti-BSA antibodies have been established. After subcutaneous immunization of mice with PHG of a lesser size MG-4, titers of specific to BSA antibodies have increased by 33.3 % compared to a larger PHG MG-8. BSA alone have not stimulate sufficient antibody responses.
Because of the containing epoxy groups in polymers, the activity of antioxidant enzymes – SOD, catalase and GP for their application have been studied. MG-4 has decreased SOD activity by 46.6 % compared to the controls. Both hydrogels have raised catalase activity by 21.6 %. The value of GP activity has been individual for all animals and within the limits of physiological oscillations. Using MG-4 activity of ALT has been increased by 1.46 and AST by 1.22 times, however, the de Ritis factor, which is noted by the ratio of activity of AST to ALT, has been normal and amounted 1.33. The application of polymer MG-8 has caused an increase in the de Ritis factor to 2.
Subcutaneous immunization with MG-4 and MG-8 leads to growth in the activity of catalase, indicating the activation of the system of antioxidant protection of the organism. The detected minor changes in the activity of SOD and ALT after immunization with MG-4 may indicate its slight toxicity. Adjuvant properties have been found for the both polymers. The use of MG-4, which has smaller size, results in higher antibody titers specific for the model antigen (BSA). The PHG with subcutaneous administration are permissible and suitable for further studies to establish safe and effective vaccines.
Article recieved: 30.08.2017
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