Co-culture of placental stem cells and stem cells from a second source

Abstract

The present invention relates to a combination of placental stem cells and stem or progenitor cells derived from a second source, wherein the combination shows improved engraftment as compared to placental stem cells or stem cells from a second source, alone. The combination is referred to as a combined stem cell population. The invention also provides in vitro and in vivo methods for identifying and producing combined stem cell populations, and models of engraftment. In accordance with the present invention, the placental stem cells may be combined with, e.g., umbilical cord blood-derived stem or progenitor cells, fetal or neonatal stem cells or progenitor cells, adult stem cells or progenitor cells, hematopoietic stem cells or progenitor cells, stem or progenitor cells derived from bone marrow, etc.

1 .- 52 . (canceled) 
     
     
         53 . A composition comprising nucleated cells from human placental perfusate and stem cells from a second source, wherein said perfusate cells and stem cells from a second source, when cultured for a time and under conditions that allow the formation of colony-forming units, together produce more colony-forming units than a number of placental perfusate cells equivalent to the number of perfusate cells and stem cells from a second source, or a number of stem cells from a second source equivalent to the number of cells in the perfusate cells and stem cells from a second source, alone. 
     
     
         54 . A composition comprising human stem or progenitor cells and isolated human placental stem cells, wherein said placental stem cells are obtained from a placental that has been drained of cord blood and flushed to remove residual blood, and wherein said placental stem cells are:
 CD200 +  and HLA-G + ;   CD73 + , CD105 +  and CD200 + ;   CD200 +  and OCT-4 + ;   CD73 + , CD105 +  and HLA-G + ;   CD73 + , CD105 +  and facilitate the formation of embryoid-like bodies in a population of isolated placental cells comprising said stem cells, when said population is cultured under conditions that allow the formation of embryoid-like bodies; or   OCT-4 +  and facilitate the formation of embryoid-like bodies in a population of isolated placental cells comprising said stem cells, when said population is cultured under conditions that allow the formation of embryoid-like bodies.   
     
     
         55 . A method of transplantation, comprising transplanting to a recipient a combination of placental perfusate cells and stem cells from a second source, wherein said combination, when transplanted, results in enhanced engraftment compared to transplantation of a number of placental perfusate cells equivalent to the number of cells in the combination, or stem cells from a second source equivalent to the number of cells in the combination, alone.