Expression of human bone-related proteins in the hematopoietic microenvironment.
Given the intimate relationship between bone and bone marrow, we hypothesized that the human bone marrow may function as a source (or reservoir) of bone-forming progenitor cells. We observed a population of cells within the bone marrow which produce bone-specific or bone-related proteins. The production of these proteins was developmentally regulated in human long-term bone marrow cell cultures; the bone protein-producing cells (BPPC) are observed under serum-free, short-term culture conditions, respond to bone-related and not hematopoietic growth factors, and are derived from a population of low-density, nonadherent, My10-negative (or low My10 density), marrow cells (My10 is an antigen found on most hematopoietic progenitor cells). Cultivation of marrow-derived BPPC in secondary, serum-containing cultures results in their differentiation into osteoblastlike cells. At this stage of development, BPPC produce an extracellular matrix which incorporates both bone-related proteins and radiolabeled calcium. Human bone marrow BPPC thus represent a newly described cell phenotype important to both bone and hematopoietic cell biology.
Long
M W
MW
Department of Pediatrics, University of Michigan, Ann Arbor 48109.
Williams
J L
JL
Mann
K G
KG
D000951:Antigens, Neoplasm / Q000096:biosynthesis; D001853:Bone Marrow / Q000254:growth & development / Q000378:metabolism*; D001854:Bone Marrow Cells; D002454:Cell Differentiation; D002478:Cells, Cultured; D005109:Extracellular Matrix / Q000378:metabolism; D006410:Hematopoiesis; D006801:Humans; D007124:Immunoenzyme Techniques; D008565:Membrane Proteins / Q000096:biosynthesis; D010006:Osteoblasts / Q000166:cytology / Q000378:metabolism; D015675:Osteocalcin / Q000096:biosynthesis*; D015676:Osteonectin / Q000096:biosynthesis; D010641:Phenotype; D014176:Protein Biosynthesis; D013234:Stem Cells / Q000166:cytology / Q000378:metabolism*
D000951:Antigens, Neoplasm; D008565:Membrane Proteins; D015676:Osteonectin; D015675:Osteocalcin