Methods for use of delivery composition for expanding, activating, committing or mobilizing one or more pluripotent, self-renewing and committed stem cells

A method for delivering a hematopoietic growth factor capable of expanding, activating, committing or mobilizing hematopoietic stem cells in a host, the method comprising:

• administering a delivery composition to the host, the delivery composition comprising:
• (i) an active agent in a quantity capable of stimulating mobilization in the host of hematopoietic stem cells, the active agent being a hematopoietic growth factor;
• (ii) a first biocompatible polymer and a liquid vehicle in which the first biocompatible polymer is at least partially soluble at some temperature, the first biocompatible polymer being a block copolymer comprising at least one block of a polyoxyalkylene and interacting with the liquid vehicle to impart reverse thermal viscosity behavior to the composition over at least some temperature range, so that the composition is in a lower-viscosity form when the temperature of the composition is at a first temperature within the range and the composition is in a higher-viscosity form when the temperature is at second temperature within the range that is higher than the first temperature;
• and
• (iii) a second biocompatible polymer being a protective colloid that inhibits dissolution of the first biocompatible polymer into aqueous biological liquids within the host, at least when the delivery composition is in the higher-viscosity form.