Table II.

Summary of main findings in pre-clinical studies of Treg cells for GvHD

Major finding	Representative references
Depletion of Treg cells from the graft exacerbates GvHD, and supplementation of Treg cells ameliorates GvHD	Cohen et al (2002), Taylor et al (2002)
Treg cells inhibit the early expansion of allogeneic conventional T cells in lymphoid organs and GvHD target organs	Edinger et al (2003)
The best therapeutic effect of transplanted Treg cells for GvHD is achieved when Treg cells are infused in early phases of inflammation	Nguyen et al (2007)
The graft-versus-tumour effect is unimpeded upon infusion of Treg cells	Edinger et al (2003), Jones et al (2003), Martelli et al (2014), Nguyen et al (2007), Trenado et al (2003)
Treg cells can ameliorate GvHD in haploidentical mouse models (in addition to fully allogeneic models)	Wysocki et al (2005), Zhang et al (2013)
Treg cells are beneficial in chronic GvHD mouse models (in addition to acute GvHD models)	Anderson et al (2004), Zhao et al (2008)
Treg cells have a therapeutic role in ameliorating GvHD in xenogeneic models	Hippen et al (2008), Hippen et al (2011), Mutis et al (2006)
The expression of FOXP3 in induced Treg cells is unstable, which impairs their ability to protect against GvHD	Beres et al (2011), Koenecke et al (2009)
Rapamycin with or without low-dose IL-2 can improve the stability of FOXP3 in induced Treg cells	Shin et al (2011), Zhang et al (2013)

GvHD: graft-versus-host disease; IL-2: interleukin 2; Treg: T regulatory.