Early-stage multipotential stem cells in colonies of bone marrow stromal cells

Abstract

Marrow stromal cells (MSCs) are adult stem cells from bone marrow that can differentiate into multiple non-hematopoietic cell lineages. Colonies of human MSCs were shown to contain both small, rapidly self-renewing stem cells (RS cells) and large, more mature cells (mMSCs). Samples enriched for RS cells had a greater potential for multipotential differentiation than samples enriched for mMSCs. Also, RS cells have a series of surface epitopes and expressed proteins that can be used to differentiate RS cells from mMSCs. The results suggest that it will be important to distinguish the two major sub-populations of MSCs in defining their biology and their potentials for cell and gene therapy.

1 - 3 . (canceled)  
   
   
       4 . A population of large, more mature marrow stromal cells (mMSC), wherein the cells within said population express one or more polypeptides selected from the group consisting of STRO-1, PDGF receptor, EGF receptor, CD10, and CD147.  
   
   
       5 . The population of cells of  claim 4 , further wherein the cells in said population express one or more polypeptides selected from the group consisting of stress protein T-complex protein 1-alpha, initiation factor 2G, ribosomal large P0, annexin V, actin β chain, lactate dehydrogenase B, phosphoglycerate kinase-1, enolase-1, and protein disulfide isomerase ER60 precursor.  
   
   
       6 . The population of cells of  claim 5 , further wherein the cells in said population express at least nine polypeptides which are not expressed in the population of small rapidly renewing stem (RS) cells.  
   
   
       7 . A method of distinguishing a population of small and rapidly self-renewing stem cells (RS) from a population of large, more mature marrow stromal cells (mMSC), said method comprising assessing whether at least about twenty-nine polypeptides are expressed in cells in said RS cell population but are not expressed in said mMSC population, and further wherein at least about nine polypeptides are expressed in said population of MSC, but are not expressed in said population of RS cells, wherein the cells within said RS cell population express one or more polypeptides selected from the group consisting of VEGF receptor-2 (FLK-1), TRK (an NGF receptor), transferrin receptor, and annexin II (lipocortin 2) and said RS cells are about seven micorns in diameter, and wherein the cells within said MSC cell population express one or more polypeptides selected from the group consisting of STRO-1, PDGF receptor, EGF receptor, CD10, and CD147 and are about fifteen to about fifty microns in diameter, thereby distinguishing said populations of cells.  
   
   
       8 . The method of  claim 7 , wherein none of said cells express any of the polypeptides selected from the group consisting of CD1a, CD11B (Mac-1), CD14, CD27, CD34, CD43, CD45, CD133, CD50 (1-CAM 3), CD53, CD109, CD114 (G-CSFR), HLA-2, CCR5 (chemokine receptor-5) and human L1 (neurite adhesion molecule).  
   
   
       9 . (canceled)  
   
   
       10 . A population of large, more mature marrow stromal cells identified by the method of  claim 8.