Alpha-1-antitrypsin in human mast cells immunofluorescent localization

Proteases are present in the cytoplasm of tissue mast cells in an active form and several explanations have been offered as to how self digestion is prevented. Our studies demonstrate that alpha-1-antitrypsin, a natural protease-inhibitor is present also in the mast cell cyt$\text{o}$ plasm. This finding suggests that a protease inhibitor complex is formed and thus could effectively prevent the proteolytic action inside the cell.