Cell populations having immunoregulatory activity, method for isolation and uses
The present invention provides a population of connective tissue derived cells that respond to interferon-gamma (IFN-γ) by expressing indolamine-2,3-dioxygenase (IDO) for use in preventing, treating or ameliorating one or more symptoms associated with disorders in which modulation of a subject's immune system is beneficial, including, but not limited to, autoimmune diseases, inflammatory disorders, and immunologically mediated diseases including rejection of transplanted organs and tissues.
1. A method for treating or ameliorating one or more symptoms associated with rheumatoid arthritis, in a subject suffering from rheumatoid arthritis, which comprises administering to said subject in need of such treatment a therapeutically effective amount of an isolated cell population of adipose tissue derived cells, wherein the cells of said cell population:
a) do not express markers specific for antigen-presenting cells (APC),
b) do not express indolamine 2,3-dioxygenase (IDO) constitutively,
c) express IDO upon stimulation with interferon-gamma (IFN-γ) and,
d) present capacity to be differentiated into at least two cell lineages.
2. The method of claim 1 , wherein the cell population does not present tumorigenic activity.
3. The method of claim 1 , wherein the cell population is negative for the following cell surface markers: CD11b, CD11c, CD14, CD31, CD34, CD45, CD133 and HLAII.
4. The method of claim 1 , wherein the cell population is positive for at least one of the following cell surface markers: CD9, CD44, CD54, CD90 and CD105.
5. The method of claim 1 , wherein the cell population is capable of being expanded ex vivo.
6. The method of claim 1 , wherein the cell population is from human origin.
7. The method of claim 1 , wherein said cell population is irradiated with a controlled source of ionizing radiation for an exposure time, wherein said exposure time is adjusted to impart a radiation dose that causes growth arrest of said cell population.
8. The method of claim 1 , wherein said cell population is treated with IFN-γ.