AUTOGRAFTING IN PHILADELPHIA (PH)-LEUKEMIA USING CULTURED MARROW - ANUPDATE OF A PILOT-STUDY( CHRONIC MYELOID)

Incubation of CML marrow in long-term culture (LTC) conditions may res ult in selection of normal (Ph-) LTC-initiating cells (LTC-IC) as earl y as 10 days, and in production of Ph- clonogenic cells and mature end cells within 5 weeks, This was the rationale for using marrow cells f rom 10-day-old LTC to autograft nine chronic phase CML patients, ineli gible for HLA-matched sibling donor transplant, and who were selected on the basis of a pre-transplant screening LTC test, Of the transplant ed patients three died; two of graft failure and one of therapy-relate d toxicity with 97% Ph- cells 16 months following the autograft, The r econstituting haemopoietic cells in the seven engrafted patients were 100% Ph- in four, greater than or equal to 90% Ph- in two and 71% Ph- in the seventh, with a duration of complete cytogenetic response of 6- 12 months. Three patients reverted to chronic phase and 100% Ph+ haemo poiesis 27-36 months post-autograft, The other three patients remain i n continuous haematological remission with 22% Ph- cells in one and co mplete cytogenetic remission in the other two 3-4 years post-autograft . IFN therapy was generally introduced on the first evidence of recurr ence of Ph+ cells or of cytogenetic deterioration, Further strategies to modulate immune surveillance in vivo may improve the outcome of cul tured marrow autografts which give an initial and rather prolonged bia s towards Ph- haemopoiesis.