International Journal of Cell Cloning, Vol 8, 171-183, Copyright © 1990 by AlphaMed Press
Bone marrow cell modulation and inhibition of myelopoiesis by large granular lymphocytes and natural killer cells
A Nagler and PL Greenberg
Department of Medicine, Stanford University Medical Center, California.
Non-adherent Percoll-separated large granular lymphocytes (LGLs)
fractionated by fluorescence-activated cell sorter into CD16+ CD4- natural
killer (NK) cells and CD16- CD4+ T cells, were co-cultured with bone marrow
(BM) cells previously depleted of adherent T and/or NK cells by
immunoadsorption (panning) and plated in a clonogenic assay to assess
myeloid colony formation (CFU-gm growth). LGLs, NK cells and LGL T cells
[low buoyant density (LBD) T cells] each significantly reduced
colony-stimulating factor (CSF)-dependent CFU-gm growth to 70% of control
values (p less than 0.05). Non-LGL T cells [high buoyant density (HBD) T
cells] did not affect this growth. Incubation of the effector cells with
human recombinant interleukin 2 prior to co- culturing did not alter these
findings. The supernatants obtained from LGLs, NK cells and LBD T cells
co-cultured with BM cells also inhibited CFU-gm growth to 70% of the
control, whereas supernatants from effector cells which were not
co-cultured with BM had no such effect. These supernatants from the LGL:BM
co-cultured cells possessed NK cytotoxic factor (NKCF), but lacked alpha
and gamma interferons, tissue necrosis factor-alpha, and prostaglandin E2.
These results suggest that BM cells stimulate LGLs to produce NKCF, and
that LGLs, CD16+ NK cells, and CD4+ CD16- LBD T cells activated by contact
with BM cells inhibit CFU-gm growth.
