title: Natural killer cell precursors in the CD44neg/dim T-cell receptor population of mouse bone marrow.
abstract: Natural killer (NK) cells develop from the nonadherent cell component of NK long-term bone marrow (BM) cultures (NK-LTBMC). Because these nonadherent cells are depleted of mature NK cells and T cells, but appear to enriched for NK precursors, they were used as a starting population to begin to define the NK precursors that function in NK-LTBMC. As the stromal cell component of NK-LTBMC has been shown to support interleukin (IL)-2-induced, CD44 dependent, NK cell development from nonadherent NK precursors, NK-LTBMC stroma was used in a limiting dilution assay (LDA) to quantitate the precursors. NK-LTBMC in 96-well plates were irradiated (20 Gy) to kill hematopoietic cells (including the NK precursors), seeded with limiting dilutions of the cells to be quantitated, cultured with 500 U/mL IL-2 for 13 days and assayed for development of NK activity by adding 51Cr-labeled YAC-1 cells to the wells and evaluating the release of 51Cr after 4 hours. Flow cytometric analysis, sorting, and quantitation of the nonadherent cell component of NK-LTBMC showed that NK precursors were concentrated in the CD44neg/dim subset that comprised 10% of the "lymphoid" gated cells. When the CD44neg/dim subset was sorted from BM of mice treated with 5-fluorouracil (5-FU) day before (-1FUBM), there were about 30% T cells, but no NK-1.1+ cells. When the T cells were removed by sorting and the CD44neg/dim, alphabeta, gammadelta T-cell receptorneg (TCR-) subpopulation was seeded onto irradiated stroma with IL-2, they proliferated, developed NK activity, became NK-1.1+ and CD44bright and remained alphabeta, gammadelta TCR-. The frequency of NK precursors in this population as estimated from the LDA was about 1/500.
authors.affiliation: Department of Radiation Oncology, Unversity of Pittsburgh School of Medicine, Pittsburgh, PA 15261 USA.
authors.forename: D V
authors.initials: DV
authors.lastname: Delfino
authors.forename: K D
authors.initials: KD
authors.lastname: Patrene
authors.forename: J
authors.initials: J
authors.lastname: Lu
authors.forename: A
authors.initials: A
authors.lastname: Deleo
authors.forename: R
authors.initials: R
authors.lastname: Deleo
authors.forename: R B
authors.initials: RB
authors.lastname: Herberman
authors.forename: S S
authors.initials: SS
authors.lastname: Boggs
mesh_terms: D000818:Animals; D001853:Bone Marrow / Q000187:drug effects; D001854:Bone Marrow Cells; D002448:Cell Adhesion; D002469:Cell Separation; D002478:Cells, Cultured; D018920:Coculture Techniques; D003114:Colony-Forming Units Assay; D003238:Connective Tissue / Q000502:physiology / Q000528:radiation effects; D005434:Flow Cytometry; D005472:Fluorouracil / Q000494:pharmacology; D006412:Hematopoietic Stem Cells / Q000145:classification / Q000166:cytology* / Q000187:drug effects; D018960:Hyaluronan Receptors; D007376:Interleukin-2 / Q000494:pharmacology; D007694:Killer Cells, Natural; D051379:Mice; D008810:Mice, Inbred C57BL; D011948:Receptors, Antigen, T-Cell; D011994:Recombinant Proteins / Q000494:pharmacology
chemical_list: D018960:Hyaluronan Receptors; D007376:Interleukin-2; D011948:Receptors, Antigen, T-Cell; D011994:Recombinant Proteins; D005472:Fluorouracil