Mammalian common lymphoid progenitor cell

Patent Number: 6908763

The stem cell identified in this patent is a type of progenitor cell that can differentiate only along the lymphoid, but not myeloid lineage. These cells are useful for situations in which lymphopoiesis is desired, for example, after lymphodepletion of a cancer patient in protocols used for homeostatic induced antitumor immunity.

The patent essentially covers a cell type that expresses specific markers. The marker combination claimed seems to c-kit(lo), IL-7R(+), and lineage negative. The independent claims of the patent are:

"A composition of mammalian common lymphoid progenitor cells", wherein at least 95% of the cells in said composition are characterized as c-kit.sup.lo, IL-7R.alpha..sup.+, lin.sup.- ; and wherein an individual c-kit.sup.lo, IL-7R.alpha..sup.+, lin.sup.- progenitor cell in said composition is capable of giving rise to each of T cells, B cells, and natural killer cells, but not to myeloid cells.

"A method of enrichment for a composition of mammalian common lymphoid progenitor cells", wherein at least 95% of the cells in said composition are characterized as c-kit.sup.lo, IL-7R.alpha..sup.+, lin.sup.- ; and wherein an individual c-kit.sup.lo, IL-7R.alpha..sup.+, lin.sup.- progenitor cell in said composition is capable of giving rise to each of T cells, B cells, and natural killer cells, the method comprising: combining reagents that specifically recognize c-kit, IL-7R.alpha. and lin markers with a sample of hematopoietic cells; and selecting for those cells that are c-kit.sup.lo, IL-7R.alpha..sup.+, lin.sup.-, to provide an enriched population of cells having lymphoid lineage progenitor activity.

"An isolated mammalian hematopoietic cell" characterized as c-kit.sup.lo, IL-7R.alpha..sup.+, lin.sup.-, wherein said cell is capable of differentiating into T cells, B cells, and natural killer cells, but not into myeloid cells.

View this patent on the USPTO website.