title: The human thymus. I. Partial characterization of nonlymphoid cells.
abstract: Human thymus was disrupted by mechanical and enzymatic techniques yielding tissue fragments and single-cell suspensions. Cell types and their distribution were determined before and after density separation. Single-cell suspensions produced by both separation procedures yielded comparable percentages of lymphoid and monocytic cells, whereas only the enzyme-treated tissue yielded epithelial cells. Less than 1% of all monocytic cells were mature. Monolayer cultures were established from fragments as well as unfractionated cells and gradient fractions. Analysis of these cultures showed that: (1) gradient separation of mechanically-prepared cell suspensions produced cultures enriched for macrophages, while epithelial cell cultures could be produced from fractionated enzyme treated tissue; (2) spindle-shaped cells may be fibroblasts or epithelial cells; (3) explant cultures have a growth pattern characteristic of other epithelial cells in vitro; (4) macrophages constitute a definite population of explanted cells and their percentages increase with time in culture; (5) macromolecular synthesis by epithelial cells in culture may be donor age dependent. Nonlymphoid cells of the human thymus can be identified by a variety of separation techniques and after monolayer culture. Characteristics of these cells are defined which may affect cell-cell interaction studies of the thymus.
mesh_terms: D000375:Aging; D002469:Cell Separation; D002478:Cells, Cultured; D002499:Centrifugation, Density Gradient; D004950:Esterases; D006801:Humans; D008264:Macrophages; D003012:Microbial Collagenase / Q000494:pharmacology; D010586:Phagocytes; D012397:Rosette Formation; D013950:Thymus Gland / Q000166:cytology* / Q000648:ultrastructure; D013997:Time Factors
chemical_list: D004950:Esterases; D003012:Microbial Collagenase