A longitudinal study of T and B lymphocytes from a three-year-old patient with severe combined immunodeficiency (SCID) in 'gnotobiotic protection'.

Fluctuations in the percentages and absolute numbers of T and B lymphocytes were observed in the peripheral blood of a patient with severe combined immunodeficiency maintained in a gnotobiotic environment. Up to 24 months of age, 72-86% of the lymphocytes had surface membrane immunoglobulin (SMIg), 37-47% bore a receptor for C3(EAC-RFC), and 3-12.5% formed spontaneous rosettes with sheep erythrocytes (E-RFC). These values persisted until 30 months, after which shifts in the percentages and absolute numbers of T and B cells were observed. A significant decrease in the proportion of SMIg-bearing cells to 20-40% (169-405 mm3), and EAC-RFC to 10.5-39% (114-259 mm3), was accompanied by a general increase in the proportion of T cells to 19-60% (141-1026 mm3), representing a lymphoid subpopulation approach to normal levels.