Polymorphonuclear Initial Stage

During the earliest stages, the first cells to react against the tubercle bacilli are the polymorphonuclear leucocytes, which encompass and phagocytose the organisms (Vorwald 1931). After intravenous injection into rabbits, this reaction was confined at first to small capillaries, and then extended to adjoining alveolar walls and spaces. Within 14 h, the polymorphonuclear leucocytes with and without tubercle bacilli were phagocytosed by the mononuclear exudate cells, which increased in number to the exclusion of the leucocytes. The tubercle bacilli thus were liberated in the cytoplasm of the exudate cell. 

In the rabbit s ear transparent chamber Ebert et al. (1948), Ebert and Barclay (1950), Sanders et al. (1951) and Dodson et al. (1954) have described some of the reactions observable microscopically 

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