ASSESSMENT OF IMMUNOTOXIC EFFECTS OF DESLORATADINE UNDER THE EXPERIMENTAL CONDITIONS IN LABORATORY ANIMALS
Research methods of immunotoxic effect of pollutants are informative even when other tests are unable to detect adverse effects of toxicant. The effect of desloratadine (third-generation antihistamine) on the immune system of laboratory animals was assessed in this paper. Experiments were carried out on adult light-colored guinea pigs weighing 300-350 g. Sensibilization was induced by intradermal injection of 200 micrograms of the drug to the external surface of the ear. Intradermal test did not cause skin changes. The percentage and absolute number of granulocytes in the control and experimental group were within the boundaries of the interval physiological norm. No significant changes in the index ratio of lymphocytes to monocytes, neutrophils to monocytes, neutrophils to eosinophils were found. In guinea pigs sensibilized with desloratadine phagocytic activity increased significantly (experiment 19,38 ± 0,50 %; control of 14,63±0,60 %, t=6,12; P<0.05), but the value of the phagocytic index was at the level of the control group (experiment 2,95±0,17 %; control 3,17±0,10 %, t=1,10; P<0.05). Analysis of the quantitative parameters of cell-mediated adaptive immunity in the experimental group showed the presence of moderately expressed changes in the structure of subpopulation of T-lymphocytes. Rising in percentage T-lymphocytes (CD3) and a significant percentage increase in T-helper (CD4) were noted in desloratadine sensibilized guinea pigs in comparison with the control group. These changes together with the increase in phagocytic activity could be regarded as an adaptive immune response on administration of the drug and no toxic effect of desloratadine on the cell-mediated immunity. The resulting index numbers of immune status of sensibilized animals had no vastly differences compared with the control. Levels of circulating immunoglobulins and immune complexes in the blood serum of guinea pigs in the control group did not differ significantly from that of control group, indicating no effect of desloratadine on the humoral immunity. The experimental results allow us to classify desloratadine as a substance that does not have immunotoxic effect.