CELLULAR REACTIONS IN THE MENINGES OF RABBITS TO TUBERCULO-LIPOID, PROTEIN, AND POLYSACCHARIDE, COMPARED WITH THE EFFECTS OF TUBERCLE BACILLI.

1. Both living and dead tubercle bacilli, as well as tuberculophosphatide, give rise to lesions in which the same type of cell is found, a cell which may prove characteristic of the meningeal reaction. After the phosphatide this cell is produced by the phagocytosis of lipoidal material. The vacuoles of these cells are slowly broken into smaller and smaller size until they correspond to the type found in the epithelioid cells with coarse vacuoles. This change is much slower in the cells of the meninges than in the cells of the omentum and subcutaneous tissue. 2. Intrathecal injections of tuberculo-protein produce a characteristic rise in temperature in normal and tuberculous rabbits. Both normal and tuberculous rabbits, after repeated intrameningeal injections of a given dose of tuberculo-protein, may fail to give a rise in temperature and later react to a larger dose.