Pleurisy induced by intrapleural BCG in immunized guinea pigs.

Guinea pigs immunized with intracutaneous BCG more than 10 weeks previously responded with pleurisy to a large dose (2 mg) of BCG injected into the right pleural cavity. The pleurisy was characterized by an initial stage in which the effusion contained predominantly granulocytes. From day 3 to day 17 after induction, lymphocytes were the dominant white cells. From the day 11 onwards there was decrease of fluid volumes and cell numbers, with concomitant induration and subsequent necrosis of regional lymph nodes, swelling of the pleural wall and formation of adhesions. Fluid volumes of 4-15 ml and total lymphocyte yields of, in general, 10-100 million during days 3-11 after induction of pleurisy, make the model suitable for chemical analyses and immunologic studies.