Methods of controlling proliferation and differentiation of stem and progenitor cells

Patent Number: 7,429,489

In addition to their usefulness for making new blood cells, hematopoietic stem cells have been demonstrated to induce regeneration of injured liver in cirrhosis patients, possess therapeutic effects in heart failure, and possible are associated with recovery of patients after strokes.  

One of the limiting factors with autologous hematopoietic stem cell therapy, and why companies such as Medistem chose to go after allogeneic cells, is because of limitations in expanding hematopoietic stem cells. The current patent seems to overcome this, or at least takes a big step towards addressing the issue of expanding autologous cells. 

The patent has 3 sets of independent claims covering: a) "an ex vivo expanded hematopoietic cell population with lower intracellular calcium in comparision to hematopoietic cells grown in absence of a calcium chelator" b) "an expanded hematopoietic cell population that is expanded by ex vivo growth in cytokines and calcium chelation" and c) "A hematopoietic cell population comprising ex-vivo expanded cells derived from peripheral blood, bone marrow and/or neonatal umbilical cord blood and characterized by reduced available intracellular copper concentration as compared to hematopoietic cells expanded ex-vivo in the absence of a transition metal chelator"

The patent covers numerous cytokine combinations and transition metal chelators such as polyamine chelating agents, ethylendiamine, diethylenetriamine, triethylenetetramine, triethylenediamine, tetraethylenepentamine, aminoethylethanolamine, aminoethylpiperazine, pentaethylenehexamine, triethylenetetramine-hydrochloride, tetraethylenepentamine-hydrochloride, pentaethylenehexamine-hydrochloride, tetraethylpentamine, captopril, pencilamine, N,N,Bis(2 animoethyl (1,3 propane diamine, 1,4,7-triazacyclononane trihydrochloride, 1-oxa-4,7,10-triazacyclododecane, and tetraethylpentamine.

View this patent on the USPTO website.