Distribution of T and B lymphocytes in blood and lymphoid tissues of fetal and adult sleep.

Distributions of B and T lymphocytes in blood and various lymphoid tissues of clinically normal adult and fetal sheep were studied. The B and T lymphocytes were identified in enriched preparations of blood lymphocytes and cell suspensions of solid tissues. The T lymphocytes were quantitated by indirect immunofluorescence, using rabbit antisera to sheep thymus cells. The B lymphocytes were identified by direct immunofluorescence, using rabbit antisera to sheep immunoglobulin.