[Immunopathologic aspects of local tuberculous tissue reactions]

The importance of immunologic factors in the local defense against myobacterial disease derives from different mechanisms of action. These may be characterized as follows: mycobacteria act as antigens or antigenic fragments to cause local sensitization, activation, and proliferation of T-lymphocytes leading to the formation of giant cells of Langhans' type. Antibodies play a role only as opsonines and are not directly responsible for the destruction of the invading organisms. Lymphokines on the other hand activate connective tissue cells and thereby contribute to the walling of infection and the development of scar tissue.