Detection of MRD by PCR analysis of V δ 1-J δ 1 junction of the TCR δ gene in a T-ALL patient. DNA samples were extracted from bone marrow aspirates performed at the onset of the disease (Diagnosis), at the end of induction chemotherapy when it was considered in complete hematologic remission (CR), from unmanipulated G-CSF mobilized CPC obtained after a consolidation course with high dose chemotherapy (Apheresis), from cells coated by anti-CD2 and -CD7 magnetic microbeads and retained within the depletion column (Unwanted cells), from the purified T-cell depleted fraction of circulating progenitor cells (Purified CPC), and from the peripheral blood lymphocytes of a normal donor (PBL). The sensitivity of the PCR reaction was checked by serial log dilution of the patient's DNA obtained at diagnosis with DNA from a normal donor (lower lane of the figure). PCR products were blotted onto nylon membranes and hybridized with the indicated clonospecific probe labeled with (γ -32 P) ATP.
