Recombinant human bone morphogenetic proteins‐2 and ‐4 induce several mesenchymal phenotypes in culture

Abstract

Bone morphogenetic protein has previously been shown to induce the formation of cartilage and bone in vivo. We have isolated a population of mesenchymal stem cells from rat skeletal muscle capable of forming multiple mesodermal morphologies in vitro. These cells were treated with recombinant human bone morphogenetic proteins-2 and -4 to determine the differentiation-inducing activities of bone morphogenetic protein on these cells. The mesenchymal stem cells were cultured in medium with 10% preselected horse serum containing 0 to 100 ng/ml recombinant human bone morphogenetic proteins-2 or -4 for a maximum of 4 weeks. Control cultures maintained the stellate morphology of mesenchymal stem cells. Cultures treated with recombinant human bone morphogenetic protein-2 exhibited discrete cartilage nodules and mineralized bone nodules. The first increase in chondrogenesis was seen at 0.5 ng/ml. Cultures treated with recombinant human bone morphogenetic protein-4 also exhibited an increase in chondrogenesis at the higher concentration of 2 ng/ml. Skeletal myotubes and adipocytes also appeared in cultures treated with either bone morphogenetic protein. Mesenchymal stem cells do respond to inductive factors, but bone morphogenetic proteins-2 and -4 were not specific for the induction of cartilage and bone.

Adult stem cells

“…We (Young, 1977a(Young, , 1977b(Young, , 1977c(Young, , 1983(Young, , 2000(Young, , 2004Young et al, 1983aYoung et al, , 1983bYoung et al, , 1983cYoung et al, , 1983dYoung et al, , 1985Young et al, , 1989aYoung et al, , 1989bYoung et al, , 1991Young et al, , 1992aYoung et al, , 1992bYoung et al, , 1993Young et al, , 1995Young et al, , 1998aYoung et al, , 1998bYoung et al, , 1999Young et al, , 2001aYoung et al, , 2001bYoung et al, , 2004aYoung et al, , 2004bLucas et al, 1993Lucas et al, , 1995Lucas et al, , 1996aLucas et al, , 1996bPate et al, 1993;Rogers et al, 1995;Dixson et al, 1996;Warejcka et al, 1996;Young and Lucas, 1998;Romero-Ramos et al, 2002) and others Jiang et al, 2002;Zhao et al, 2003) (see also Table 1) have observed that many tissues and organs contain a wide variety of precursor cells. The precursor cells observed include pluripotent epiblasticlike stem cells, pluripotent ectodermal stem cells, PPMSCs, and pluripotent endodermal stem cells; and multipotent, tripotent, bipotent, and unipotent progenitor cells.…”

“…These studies began with initial observations on the origins of the blastema cells during limb regeneration in terrestrial amphibians (Young, 1977a(Young, , 1977b(Young, , 1977c(Young, , 1983Young et al, 1983aYoung et al, , 1983bYoung et al, , 1983cYoung et al, , 1983dYoung et al, , 1985Young et al, , 1989aYoung et al, , 1989b. The studies have progressed through precursor cell identification in the connective tissues of avians Young et al, 1991Young et al, , 1992aYoung et al, , 1992bYoung et al, , 1992cYoung et al, , 1993Young et al, , 1995Young et al, , 1998aLucas et al, 1994a;Dixson et al, 1996;Young and Lucas, 1998;Young, 2000), mammals (Shoptaw et al, 1991;Lucas et al, 1992Lucas et al, , 1993Lucas et al, , 1994aLucas et al, , 1994bLucas et al, , 1995Pate et al, 1993;Grande et al, 1995;Rogers et al, 1995;Warejcka et al, 1996;Young and Lucas, 1998;Young et al, 1998bYoung et al, , 2001aYoung et al, , 2004aYoung et al, , 2004bRomero-Ramos et al, 2002;Young, 2004), and humans ,...…”

Clonogenic analysis reveals reserve stem cells in postnatal mammals: I. Pluripotent mesenchymal stem cells

“…Mesodermal stem cells have been isolated and identified in multiple animal species, including avians (Young et al, 1992a, mice (Rogers et al, 1995;Saito et al, 1995;Young et al, 1998a), rats (Grigoriadis et al, 1988;Lucas et al, 1995Lucas et al, , 1996Dixon et al, 1996;, rabbits (Pate et al, 1993;Wakitani et al, 1994;Grande et al, 1995;R.G. Young et al, 1998), and humans (Caplan et al, 1997;Young et al, 1999;Young, 2000).…”

Tissue Engineering

“…Mesenchymal stem cells may be expanded in vitro and either be directly implanted at high concentrations in damaged sites or first cultured in the presence of the appropriate growth factors to reconstruct a tissue similar to the native one in which they will be implanted (Kasugai et al, 1991;Dixon et al, 1996). These cells implanted in sites of osteochondral defects completely repair and restore the physiological function of the tissue.…”

“…Various experiments conducted in vitro likely suggest that mesenchymal progenitor cells can be easily pushed through the osteoblast/osteocyte differentiation lineage using specific inducers (Kasugai et al, 1991;Dixon et al, 1996;Young et al, 1998). In addition, some evidence has been shown that in vivo progenitor mesenchymal cells may be driven to the correct differentiation pathway by the influence of different stimuli exerted by the surrounding microenvironment (Wakitani et al, 1994).…”