The ability to purify and characterize phenotypic markers of human bone pre
cursor cells provides an important means to study the basis of age- or dise
ase-related changes in osteogenesis. Utilizing immunologically purified and
characterized populations of human bone preosteoblast-like cells, we demon
strate that distinct age-related alterations occur in bone cell phenotypic
markers, and additionally document the presence of a subpopulation of elder
ly individuals who express markedly reduced amounts of bone proteins. These
findings provide insights into the early phases of bone cell development,
and provide a means for evaluating age- and/or disease-mediated changes in
bone cell development.