11. Non-pregnant and non-nursing. Women and men of reproductive potential should agree to use an appropriate method of birth control throughout their participation in this study due to the teratogenic potential of the therapy utilized in this trial (although it is unlikely that successful pregnancy will occur in patients with chronic GvHD). Appropriate methods of birth control include oral contraceptives, implantable hormonal contraceptives (Norplant®), or double barrier method (diaphragm plus condom).