[Activity of lysosomal proteinases in mouse macrophages, spleen and thymus during formation of the immune response].

Activity of lysosomal proteinases cathepsins A, B, C, D, H and L was studied in peritoneal macrophages, spleen and thymus of mice CBAXC57BL/6 strain in dynamics of immune response formation to sheep erythrocytes from 0.5 hr to 96 hrs. The most distinct alterations in the enzymatic activity were detected in macrophages. Activity of the enzymes studied was sharply decreased within 0.5 hr after immunization and then increased gradually, attaining maximal rates within 4 days. Two-phase increase in activity of cathepsins D and thiol-dependent proteinases cathepsins B, L and H was found in spleen within 0.5-6 hrs and 96 hrs after the antigen stimulation. Dynamics of individual cathepsins activity was dissimilar in thymus but the activity was mainly increased during 24-48 hrs of the antigen stimulation. The data obtained suggest that activity of lysosomal proteinases was distinctly altered in dynamics of the immune response development attaining its maximal values at the peak phase of humoral immunity formation.