Table 1. Antigen-dependence of CD19 CAR-targeted T cells in the BM.

			Week 1
	B lineage cells/femur				Donor Tcells/femur
1×106	3.0×106	9.0×106		1×106	3×106	9×106
2.0×105	3.1×104	6.2×104		5.8×104	1.5×104	3.2×104
1.5×105	1.6×105	1.6×105		1.6×104	7.5×104	6.5×104
1.1×105	1.1×105	1.4×105		3.1×104	6.1×104	1.1×105
1.0×105	1.1×105	9.8×104		4.4×104	5.7×104	9.8×104
1.1×105	7.7×104	6.7×104		5.6×104	1.0×105	4.0×104
			E∶T ratio	1∶4.0	1∶1.7	1∶1.7
			% Dose	65.1	32.9	11.9

B and congenic T cell counts from the BM of mice treated with cyclophosphamide (300 mg/kg) and increasing doses (labeled in bold) of congenic m1928z T cells. Mice were sacrificed 1 and 5 weeks after adoptive transfer with congenic T cells and flow cytometry for B cell (B220) and congenic T cells (Thy1.1/Thy1.2) was performed on single-cell suspensions of the BM. Counts were facilitated with Countbright beads (Invitrogen). E∶T ratio is the ratio of congenic donor T cells to B cells in the BM.% Dose is the m1928z T cell dose divided by the total number of BM congenic T cells, estimated by multiplying the femoral congenic T cell count by 15.8 [5].