Chimerism analysis in bone marrow (BM) or peripheral blood (PBL) from the patient after treatment with donor lymphocyte infusion (DLI). Cells of donor (HS) origin could be detected by AFP polymorphism (heterozygous 145 and 72 bp fragments). Temporary increase of donor cells was observed in MNC in BM at 8 weeks after DLI, but returned to pre-treatment levels at 16 weeks after DLI. PMN from the patient remained of patient origin.