The effect of immunization with foreign proteins on the activity of mitochondria in rat thymocytes and splenocytes

Studies of cellular metabolism in development of immunological memory is still relevant since it can help to deepen our knowledge on pathogenesis of immune-inflammatory diseases and provide a basis for improving their prevention and treatment. The aim of the present study was to evaluate the activity of mitochondria in thymocytes and splenocytes after immunization of rats with human albumin. Male Wistar rats were immunized with human albumin for 4 days. The total amount of protein injected was 135 mg. 24 hours after the last injection, we evaluated hematological parameters (general blood test), and mitochondrial activity of thymocytes and splenocytes by measuring rhodamine 6 G fluorescence by means of the Evos M7000 imaging system in RFP mode. We also calculated the mass ratios of the thymus and spleen relative to the body mass of the animals. Statistical analysis included assesment of the median, upper and lower quartiles, and comparisons of hypotheses using the Mann–Whitney U test and correlation analysis according to Pearson’s method. Hypertrophy of the thymus was revealed in animals of the immunized group by 56.9%, p = 0.032, and no changes in the mass of the spleen were observed. A decreased mitochondrial fluorescence was detected in thymocytes by 23.5% (p = 0.037) and splenocytes by 13.7% (p = 0.548) which may be associated with immunosuppressive effect of TGF-β during repeated administration of a foreign protein. Moreover, we have found monocytosis exceeding the control by 59.4%, (p = 0.030), along with thrombocytopenia (by 20.8%, p = 0.045). These changes, were observed in experimental rats thus reflecting reactive changes occurring during immunization. At the early stages after immunization of animals, we have revealed inhibition of energy exchange in thymic and spleen cells. This finding may reflect the effects of inflammatory mediators on mitochondria of lymphocytes and to suggest promising targets for treatment of immuno-inflammatory disorders.

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