Pure populations of astrocyte restricted precursor cells and methods for isolation and use thereof

Abstract

An isolated, pure homogeneous population of mammalian astrocyte restricted precursor cells which is CD44 immunoreactive and which generate astrocytes but not oligodendrocytes is provided. Methods for identifying, isolating and using these mammalian astrocyte restricted precursor cells are also provided.

What is claimed is: 
     
         1 . An isolated population of mammalian precursor cells which generate astrocytes but not oligodendrocytes, said cells being CD44+. 
     
     
         2 . A method for treating damaged neural cells in a mammal, said method comprising administering to a mammal with damaged neural cells the mammalian precursor cells of  claim 1 . 
     
     
         3 . The method of  claim 2  wherein the mammalian precursor cells are administered to the mammal by direct injection into or near a site of nerve damage. 
     
     
         4 . The method of  claim 2  wherein the mammalian precursor cells are administered to the mammal as an implant seeded or coated with the mammalian precursor cells. 
     
     
         5 . The method of  claim 4  wherein the implant is implanted at or near a site of damaged neural cells in the mammal. 
     
     
         6 . The method of  claim 2  wherein administering the mammalian precursor cells to the mammal enhances survival of the damaged neural cells. 
     
     
         7 . The method of  claim 2  wherein administering the mammalian precursor cells to the mammal reduces scar formation. 
     
     
         8 . An astrocyte generated or differentiated from a population of mammalian precursor cells which are CD44+ and which generate astrocytes but not oligodendrocytes. 
     
     
         9 . An astrocyte generated or differentiated from a mammalian precursor cell which generate astrocytes but not oligodendrocytes, said precursor cell being nestin+, A2B5−, and E-NCAM− or Pax-6−. 
     
     
         10 . A method of identifying a population of mammalian astrocyte restricted precursor cells which generate astrocytes but not oligodendrocytes, said method comprising identifying from a heterogeneous or mixed population of mammalian cells or tissue CD44+ cells that differentiate to astrocytes but not oligodendrocytes. 
     
     
         11 . The method of  claim 10  further comprising isolating from the heterogeneous or mixed population of mammalian cells or tissue the CD44+ cells that differentiate to astrocytes but not oligodendrocytes. 
     
     
         12 . The method of  claim 11  wherein the CD44+ cells that differentiate to astrocytes but not oligodendrocytes are isolated by immunopanning, magnetic bead sorting and/or FACS sorting using CD44 as the selection marker. 
     
     
         13 . The method of  claim 11  wherein the isolated population of CD44+ cells that differentiate to astrocytes but not oligodendrocytes is enriched by reselecting from a mixed population cells that express CD44 but do not express E-NCAM. 
     
     
         14 . The method of  claim 11  wherein the isolated population of CD44+ cells that differentiate to astrocytes but not oligodendrocytes is enriched by reselecting from a mixed population cells that express CD44 but do not express A2B5. 
     
     
         15 . The method of  claim 11  wherein the isolated CD44+ cells that differentiate to astrocytes but not oligodendrocytes generate astrocytes under conditions in which other cell populations differentiate into neurons or oligodendrocytes.