[Ultrastructure of epithelioid cells in the dynamics of forming tubercular granules]

As shown by ultrastructural findings in epithelioid cells, their number and differentiation degree increase in granulomas of animals with chronic generalized tuberculosis. Isoniazid treatment stimulated differentiation of the monocytes into epithelioid cells and differentiation of the latter. A large number of epithelioid cells with adequate lysosomal apparatus may denote a risk of the destructive process in the affected organs. The efforts in the search for new potent anti-tuberculous drugs should be focused on their lysosomotropy, ability to stay long in the lysosomal apparatus being bactericidal and bacteriostatic, and to stimulate plastic processes in the macrophages.