Role of Regulatory T Cells in Tumor-Bearing Mice Treated with Allo-Hematopoietic Stem Cell Transplantation Plus Thymus Transplantation

Table 1

Effects of T_reg cells in tumor-bearing mice treated with allo-HSCT + TT

Group	TT	Comparison of Treg cells				Effect of HSCT + TT^§	Ref.
		No treated^#	HSCT	HSCT + TT	HSCT + DLI
1. No tumor	AT		→	↓	↓↓	aGVH, elevated T cell function	[1, 8]
2a. Early tumor	AT	↑↑	↑	→	ND	GVT^a, LS^a,	[8, 10]
2b. Same as above	NT	↑↑	↑	→	ND	GVT^b, LS^b, IFNγ^b, EM T cells^b, and MS cells^c	[10]
2c. Same as above	FT	↑↑	↑	→	ND	GVT^b, LS^d	[10]
3. Advanced tumor	FT	↑↑↑	↑↑	↑	ND	Inhibition of metastasis, LS	[9]
4. Leukemia	AT	ND	→	↓	↓↓	GVL, aGVH, and LS	[11]

% of FoxP3⁺ cells in CD4⁺ T cells compared with non-tumor-bearing mice: no change, →: mild increase, ↑; moderate increase, ↑↑; strong increase, ↑↑↑; slight decrease, ↓; moderate decrease, ↓↓. ^#Host-derived cells. ^§Compared with HSCT and/or HSCT + DLI in the same group. ^a3rd in group 2, ^b1st in group 2, ^clowest in group 2, ^d2nd in group 2. AT: adult thymus; NT: newborn thymus; FT: fetal thymus; aGVH: attenuated graft-versus-host; GVT: graft-versus-tumor; LS: longest survival; EM: effector memory; MS: myeloid suppressor; GVL: graft-versus-leukemia; ND: not determined.