Medium containing flt3 ligand for culturing hematophoietic cells

Patent Number: 6919206

This patent covers the use of flt-3 ligand for expanding hematopoietic stem cells in vitro. The importance of expansion techniques is seen in that numerous groups have tried and are still trying to identify ways of generating large populations of autologous stem cells. The patent is pretty straight-forward and has 2 independent claims:

A hematopoietic cell expansion medium, comprising a cell growth medium and: (a) a polypeptide comprising amino acids 28-160 of SEQ ID NO:6; (b) a polypeptide comprising a fragment of ammino acids 28-160 of SEQ ID NO:6, wherein the fragment binds flt3; and © a polypeptide that binds flt3 that is at least 90% identical to amino acids 28-60 of SEQ ID NO:6.

An in vitro method for expanding hematopoietic cells, the method comprising contacting the cells with: (a) a polypeptide comprising amino acids 28-160 of SEQ ID NO:6; (b) a polypeptide comprising a fragment of acids 28-160 of SEQ ID NO:6, wherein the fragment binds flt3; and © a polypeptide that binds flt3 that is at least 90% identical to amino acids 28-160 of SEQ ID NO:6 in an amount sufficient to cause hematopoietic cell expansion.

View this patent on the USPTO website.