CELL-BASED TISSUE ENGINEERING THERAPIES - THE INFLUENCE OF WHOLE-BODYPHYSIOLOGY

A technology has been developed to isolate a developmentally and pheno typically homogeneous population of pluripotent human mesenchymal stem cells (hMSCs) from adult bone marrow and mitotically expand these cel ls in culture. These hMSCs have osteoblasts as one of their potential developmental end-stage phenotypes, and, in addition to their osteogen ic potential, these hMSCs synthesize and secrete a variety of macromol ecules that are known regulators of osteoclast differentiation and act ivity. In this review, data are presented that demonstrate the phenoty pic and developmental homogeneity of the cells in hMSC cultures, as we ll as their ability to differentiate along multiple phenotypic pathway s and serve as regulatory cells for hematopoietic and bone-resorbing c ells. In addition, a logic and preliminary data are presented that sup port the use of hMSCs in the prevention and treatment of age-related a nd postmenopausal osteoporosis. Since hMSC differentiation and phenoty pic expression are controlled by regulatory molecules synthesized and secreted by a variety of local and systemic mechanisms, the issue of w hole organism physiology is addressed in considering tissue engineerin g logics. (C) 1998 Elsevier Science B.V. All rights reserved.