Natural killer cell precursors in the CD44neg/dim T-cell receptor population of mouse bone marrow

摘要: Natural killer (NK) cells develop from the nonadherent cell component of NK long-term bone marrow (BM) cultures (NK-LTBMC). Because these are depleted mature and T cells, but appear to enriched for precursors, they were used as a starting population begin define precursors that function in NK- LTBMC. As stromal NK-LTBMC has been shown support interleukin (IL)-2-induced, CD44 dependent, development stroma was limiting dilution assay (LDA) quantitate precursors. 96-well plates irradiated (20 Gy) kill hematopoietic (including precursors), seeded with dilutions be quantitated, cultured 500 U/mL IL-2 13 days assayed activity by adding 51Cr-labeled YAC-1 wells evaluating release 51Cr after 4 hours. Flow cytometric analysis, sorting, quantitation showed concentrated CD44neg/dim subset comprised 10% “lymphoid” gated cells. When sorted BM mice treated 5- fluorouracil (5-FU) day before (-1FUBM), there about 30% no NK-1.1+ removed sorting CD44neg/dim, alphabeta, gammadelta T-cell receptorneg (TCR-) subpopulation onto IL-2, proliferated, developed activity, became CD44bright remained TCR-. The frequency this estimated LDA 1/500.