Stimulation of hematopoietic cells in vitro

Patent Number: 7,276,371

Ex vivo expansion of CD34 hematopoietic stem cells is a highly desired goal. If it was possible to effectively expand these cells, then not only would autologous hematopoietic stem cell transplants be more clinically successful, but also numerous ex vivo cellular therapies would be possible. Unfortunately, many companies have developed numerous ex vivo cell expansion methodologies for CD34 cells and to our knowledge none of them have become a clinical success.

The current patent covers the inhibition of a type of enzyme called dipeptidylpeptidase type IV for the ex vivo expansion of hematopoietic stem cells. The patent also covers the use of specific inhibitors of this enzyme for CD34 expansion.

CD26 is a member of the dipeptidylpeptidase type IV enzyme family and numerous papers support the modulation of CD26 as a means of manipulating various functions of hematopoietic stem cells.

Interestingly dipeptidylpeptidase type IV modulators are already clinically approved for treatment of type II diabetes (Vildagliptin). Do diabetics who take this drug have altered hematopoietic stem cell cycling/differentiation?

View this patent on the USPTO website.