Enhanced MSC preparations
The present invention provides preparations of MSCs with important therapeutic potential. The MSC cells are non-primary cells with an antigen profile comprising less than about 1.25% CD45+ cells (or less than about 0.75% CD45+), at least about 95% CD105+ cells, and at least about 95% CD166+ cells. Optionally, MSCs of the present preparations are isogenic and can be expanded ex vivo and cryopreserved and thawed, yet maintain a stable and uniform phenotype. Methods are taught here of expanding these MSCs to produce a clinical scale therapeutic preparations and medical uses thereof.
1. A mesenchymal stem cell (MSC) preparation comprising:
a. at least 1 billion cultured human bone marrow-derived MSCs expanded from a cryopreserved in-process intermediate MSC preparation; and
b. an antigen and activity profile comprising:
i. less than 0.75% CD45+ cells;
ii. at least 95% CD105+ cells;
iii. at least 95% CD166+ cells; and
iv. capable of inhibiting IL2Rα expression by CD3/CD28-activated PBMCs by at least 30% relative to a control.
2. The MSC preparation of claim 1 , wherein the at least 1 billion cultured human bone marrow-derived MSCs are isogenic.
3. The MSC preparation of claim 2 , wherein the MSC preparation comprises at least 20 billion cultured human bone marrow-derived MSCs in number.
4. The MSC preparation of claim 1 , wherein the MSCs express about 13 pg to about 44 pg TNFRI per million MSCs and wherein the MSCs inhibit IL2Rα expression by CD3/CD28-activated PBMCs when mixed with peripheral blood mononuclear cells (PBMCs) at a ratio of about 5 PBMCs per MSC.
5. The MSC preparation of claim 4 , wherein the MSCs are isogenic and are at least 4.5×10 9 human bone marrow-derived MSCs in number.
6. The MSC preparation of claim 5 , further comprising a cryopreservative.
7. The MSC preparation of claim 6 , wherein after a freeze-thaw cycle, at least 70% of the MCSs are viable, as assessed by dye exclusion.
8. The MSC preparation of claim 5 , wherein the MSCs:
a. are capable of at least 1 population doubling; and
b. retain said antigen and activity profile after the population doubling.
9. The MSC preparation of claim 5 , wherein the MSCs:
a. are capable of at least 1 population doubling; and
b. retain the differentiation capacity after the population doubling.
10. The MSC preparation of claim 1 , wherein the preparation contains less than 55 μg/ml BSA and less than 42 μg/ml trypsin.
11. The MSC preparation of claim 1 , wherein the preparation is substantially free of:
a. mycoplasma, endotoxin, and fungi; and
b. HTLV1, HTLV2, HBV, CMV, EBV, HHV-6A, HHV-6B, HHV-8, HIV, Parvovirus B-19, HCV, and HPV Type 18 viral nucleic acids.