Polymerase chain reaction (PCR)-based analyses of TCRG gene rearrangement reveal loss of patient T-ALL clones in NS122 xenografts associated with T-ALL immunophenotype change. (A) PCR analysis of TCRG gene rearrangement was performed on T-ALL 6007, which maintained the same immunophenotype in NS122 xenografts (lanes 2-7) and T-ALL 4936 (lanes 8-12), which exhibited immunophenotype change from less than 5% CD1a⁺ cells in the patient sample to more than 95% CD1a⁺ cells in xenografts. DNA from NOD thymus and NS endogenous lymphoid tumor (lymphoma) were used to detect amplified products from murine TCR rearrangement. Monoclonal and polyclonal DNA templates provided by the manufacturer and water were used as controls. The arrow indicates a Vγ9,11+Jγ1/2 PCR product found in the 4936 patient sample (lane 8) not found in primary (lanes 9-10) or secondary (lanes 11-12) NS122 xenografts. RF, right femur; BM, bone marrow. (B) T-ALL 5178 patient sample had 5% CD5⁺ cells but some NS122 xenografts had more than 90% CD5⁺ cells. PCR analysis of TCRG rearrangement was performed on the patient sample (lane 2), 1 primary (lanes 3-4), and 2 secondary (lanes 5-13) NS122 xenografts that had greater than 90% CD5⁺ cells. The arrows indicate Vγ1f-8,10+Jγ1/2 and Vγ9,11+Jγ1/2 PCR products found in the patient T-ALL sample not found in the primary and secondary NS122 xenografts. RF, right femur; BM, bone marrow; LN, lymph node.