The in vivo development of plasma cells: a morphologic study of human cerebrospinal fluid.

This is a case study of a patient with the clinical diagnosis of meningoencephalitis. It demonstrates the in vivo development of plasma cells in the central nervous system. All the stages of in vitro mitogen-induced lymphocyte transformation previously described by light and electron microscopy are recapitulated in this analysis of cerebrospinal fluid. It is postulated that this represents a local humoral immune reaction in the central nervous system and provides morphologic support for the concept that the gamma globulin in cerebrospinal fluid is produced locally in part, in addition to its origin from the plasma proteins.