Engraftment and differentiation

For engraftment studies of human stem cell preparations, both adult (6-8 weeks) or newborn (3-4 days) immunodeficient mice are used (NOD/SCID, NOD/SCID IL-2/2).

Mice can be sublethally irradiated before transplantation to additionally depress the immune system.

EPO recommends different routes of stem cell application in adult mice:

A) Systemically intraveneous administration of stem cell preparations. Recommended cell dose is in the range of 5x10⁵ - 5-10⁶ stem cells per animal.

B) Intrahepatic application of stem cells. About 5x10⁵-1x10⁷ cells per animal are necessary. Using newborn mice, about 5x10⁵ stem cells are transplanted.

C) Intraperitoneal inoculation.

Engraftment of transplanted stem cell preparations in mouse organs is monitored for several weeks after transplantation.

Differentiation of stem cells in mouse organs can be analysed by FACS analysis and immunochemistry on the basis of commercial or customer supplied antibodies. For human adult haematopoietic stem cells, CD34, CD38, c-kit, marker for T-cell differentiation (CD4, CD8), B-cell differentiation (CD19), NK-cells (CD56; CD57) and a panel of lineage specific differentiation markers, can be applied.

The multilineage differentiation of human and mouse embryonic cells under in vivo conditions in mouse organs are detected by TaqMan analysis and immunohistochemistry using a panel of tissue specific primers and species or antigen specific antibodies.

CD34+ cord blood stem cells engrafted in the bone marrow eight weeks after intravenous application. Cell differentiation is analysed by FACS. 38% of the engrafted cells expressed on their surface CD38 and 21% CD38/CD34.