Pneumocystis carinii: new separation method from lung tissue.

A new method of separating Pneumocystis carinii from infected rat, human, and mouse lung tissue has been developed, based, in part, on techniques used for the separation of lymphocytes from hematopoietic and lymphoid organs. The lungs are homogenized with a Teflon pestle and fine wire-mesh screen, digested with collagenase and hyaluronidase, and centrifuged on a discontinuous Ficoll-Hypaque density gradient. The method produces no morphologic alterations in P. carinii, as judged by light and electron microscopy. The method has been adapted for the quantitation of P. carinii in tissues and the production of antisera in rabbits.