Progenitor cell populations , expansions thereof, and growth of non-hematopoietic cell types and tissues therefrom

Abstract

Described is a method of expanding human progenitor calls by suspension culturing under non-static conditions. The culturing method provides a three-dimensional space for the rapid expansion of desirable progenitors. By this method, a new compartment of multipotential progenitor cells has been identified, which give rise under differentiation conditions to progeny including osteoblasts, chondrocytes, myoblasts, adipocytes, and other non-hematopoietic cell types. Their use in cell and tissue-based engineering is described.

We claim:  
     
         1 . An enriched progenitor cell population comprising non-hematopoietic progenitor cells extractable from bone marrow, wherein the cell population is substantially devoid of at least one type of hematopoietic progenitor cell.  
     
     
         2 . An enriched progenitor cell population according to  claim 1 , characterized by the absence of at least one hematopoietic progenitor cell type, wherein said cell type is one having a surface marker selected from CD3, CD14, CD39, CD45, CD66, CD119.  
     
     
         3 . An enriched progenitor cell population according to clam 1, wherein the population is substantially devoid of at least one of the progenitor cell types bearing an MHC determinant selected from HLA-A, HLA-B, WA-C, HLA-DR, HLA-DP and HLA-DQ.  
     
     
         4 . An enriched progenitor cell population according to  claim 2 , wherein the population is substantially devoid of progenitor cell types that bear any MHC determinant selected from HLA-A, HLA-B, HLA-C, HLA-DR, HLA-DP and HLA-DQ.  
     
     
         5 . A method for expanding human non-hematopoietic progenitor cells, the method comprising the step of subjecting a progenitor cell population comprising non-hematopoietic progenitor cells to non-static suspension culturing in a suitable medium for a period of time effective to expand said progenitor cells.  
     
     
         6 . The method according to  claim 5  wherein said progenitor cell population comprises human mesenchymal progenitor cells.  
     
     
         7 . The method according to  claim 5 , wherein said progenitor cell population is an enriched progenitor cell population according to any one of claims  1 - 4 .  
     
     
         8 . The method according to any one of claims  5 - 7 , wherein said growth medium includes growth factors for human mesenchymal progenitor cells.  
     
     
         9 . The method according to any one of claims  5 - 7 , wherein the growth medium excludes at least one factor specific for the growth of hematopoietic progenitor cells.  
     
     
         10 . The method according to  claim 8  or  claim 9  wherein said growth factors are cytokines.  
     
     
         11 . The method according to  claim 10  wherein said cytokines are a mixture of stem cell factor and interleukin-3.  
     
     
         12 . The method according to any one of claims  5 - 10  wherein said suspension is stirred during said effective period of time.  
     
     
         13 . The method according to  claim 11 , wherein said suspension is maintained at a temperature of about 37° C. during said effective period of time.  
     
     
         14 . A population of expanded human progenitor cells, characterized in that: 
 1) when cultured under conditions appropriate for differentiation, said population is able gives rise to differentiated cell types that include bone cells, fibroblast cells and neuronal cells;    2) the population has been expanded in suspension culture;    3) the progenitor cells within the population have not been selected on the basis of adherence;    4) the population phenotype is SH4 negative, and    5) the population results from culturing in the absence of at least one culture supplement specific for hematopoietic progenitor cell maintenance.    
     
     
         15 . An expanded progenitor cell population, prepared by the suspension culturing of an enriched progenitor cell population according to any one of claims  1 - 4 .  
     
     
         16 . A composition, useful for delivering non-hematopoietic progenitor cells to an environment conducive to the formation of differentiated cells therefrom, the composition comprising an expanded population of human progenitor cells according to any one of claims  1 - 4 ,  14  or  15 , and a vehicle for delivering said cells to said environment.  
     
     
         17 . A progenitor cell population as claimed in any one of clams 14, 14 and 15, in combination with one or more factors for inducing the differentiation thereof.  
     
     
         18 . A method for producing non-hematopoietic cells, comprising the steps of subjecting a progenitor cell population comprising non-hematopoietic progenitor cells to non-static suspension culturing in a suitable, medium for a period of time effective to expand said progenitor cells, and then delivering the expanded progenitor cells or a subpopulation thereof to an environment conducive to the differentiation thereof into the desired-cell type.  
     
     
         19 . A method of providing cells differentiated from mesenchymal progenitor cells, comprising the steps of subjecting a progenitor cell population comprising mesenchymal progenitor cells to non-static suspension culturing in a suitable medium for a period of time effective to expand said progenitor cells, and then delivering the expanded progenitor cells or a subpopulation thereof to an environment conducive to the differentiation thereof into a mesenchymal cell type.  
     
     
         20 . The method according to  claim 19 , wherein the expanded progenitor cells or a subpopulation thereof are delivered to an environment conducive to the differentiation thereof into bone cells.  
     
     
         21 . The method according to  claim 19  wherein the expanded progenitor cells or a subpopulation thereof are delivered to an environment conducive to the differentiation thereof into chondrocytes.  
     
     
         22 . The method according to  claim 18 , wherein the expanded progenitor cells or a subpopulation thereof are delivered to an environment conducive to the differentiation thereof into myoblasts.  
     
     
         23 . The method according to  claim 18 , wherein the expanded progenitor cells or a subpopulation thereof are delivered to an environment conducive to the differentiation thereof into neural cells.  
     
     
         24 . The method according to  claim 18 , wherein the expanded progenitor Cells or a subpopulation thereof are delivered to an environment conducive to the differentiation thereof into adipocytes.  
     
     
         25 . The method according to  claim 18 , wherein the expanded progenitor cells or a subpopulation thereof are delivered to an environment conducive to the differentiation thereof into endothelial cells.  
     
     
         26 . A cell population representing a new compartment of progenitor cells, said cell population comprising progenitor cells which, under differentiation conditions give rise to a variety of non-hematopoietic cell types including osteoblasts, adipocytes and myoblasts, wherein said cell population results from the non-static suspension culturing of an input population of progenitor cells obtained without prior selection based on cell adherence.