Periosteally derived osteoblast-like cells differentiate into chondrocytes in suspension culture in agarose

Abstract

Pluripotent cells from the periosteal layer adjacent to cortical bone attain an osteoblast-like phenotype in culture when reaching confluence in monolayer. It is unknown whether such newly differentiated osteoblast-like cells preserve the chondrogenic potential characteristics for stem cells derived from the periosteum. Primary osteoprogenitor cells derived from bovine metacarpal periosteum were differentiated into alkaline phosphatase-positive osteoblast-like cells by an established monolayer culture protocol. After transfer into suspension culture in agarose gels, the cells differentiated into chondrocytes demonstrated by the production of collagen II, but not of collagen I, as well as alkaline phosphatase activity was abated. Contrarily, with continuation of monolayer culture, the cells maintained their osteoblast-like phenotype and secreted large amounts of collagen I and a minor quantity of collagen III and V. The alkaline phosphatase activity steadily increased during the entire culture period of 2 weeks. Thus, our culture techniques can serve as useful tools to study mechanisms of differentiation by modulating the phenotypic potential of osteogenic cells. The results presented here support the notion that the extracellular environment strongly influences the cell type and its metabolism.

Multilineage mesenchymal differentiation potential of human trabecular bone‐derived cells

“…However, there is a growing body of evidence suggesting that not only marrow stroma-derived cells, but also more defined cell types of mesenchymal origin, such as adipocytes, myoblasts and chondrocytes, can differentiate or transdifferentiate into other cell types in addition to their default lineage [I 1,33,46]. Recently, periosteally derived cells, which attain an osteoblast-like phenotype in culture, have been shown to differentiate into chondrocytes when further cultured in suspension in agarose gels [4]. Interestingly, Gundle et al [19] have shown that osteoblastic cells derived from trabecular bone fragments, when implanted subcutaneously in diffusion chambers and continuously treated with osteo-inductive agents, give rise to mineralized tissue containing cartilage.…”

Cambium cell stimulation from surgical release of the periosteum

“…With age, the periosteum diminishes in thickness and osteogenic potential. While the cambium cells provide the osteogenic potential they have also demonstrated their capabilities to differentiate into chondrocytes [2,4,6,9,10,12,13,15,16,20].…”

Injectable hydrogel/micro-composite systems for in situ therapeutic cell delivery

“…However, common (synthetic or polysaccharide) hydrogels possess an extremely hydrophilic nature, which resists not only the adsorption of proteins, but also the unfolding of protein structure and exposure of specific domains (such as RGD). As a result, once One typical case may well represent the dilemma of using hydrogel encapsulation for cell delivery: the identical agarose gels that reportedly could preserve the chondrocytic phenotype (and could even induce the dedifferentiated cells to redifferentiate) [72], were evidenced to inhibit osteoblastic proliferation and the expression of typical bone markers such as type I collagen (Col I) and alkaline phosphatase (ALP) [73]. Other attempts to conduct osteogenesis in a polymer-based hydrogel have also encountered similar problem, that the viability of hMSCs (progenitor cells of osteoblasts) was heavily impaired during osteogenic induction [74,75].…”

“…Similarly, the primary bovine osteo-progenitor cells were observed by others to lose some 20% population in agarose gels after one week [73]. Accordingly, researchers have attempted to conjugate bioactive substances into the gel bulk and achieved some improvement in the cell viability [23,75].…”