Tissue cystine content in Ctns−/− mice treated with WT BMCs compared with Ctns−/− mice treated with Ctns−/− BMCs. (A) Cystine content at 2 and 4 months in Ctns−/− mice. Cystine levels increase with time after transplantation of Ctns−/− BMCs (×). In contrast, cystine content decreases in time after therapy with WT BMCs (▴). (B) Table of percentage decrease in cystine content of Ctns−/− mice treated with WT BMCs compared with Ctns−/− mice treated with Ctns−/− BMCs.