TCR gamma/delta profiles were analyzed in 13 multiple myeloma patients after allogeneic non-myeloablative transplantation. Results show that both aGVHD and minimal residual disease (MRD) eradication did significantly affect TCR gamma/delta profile. During follow-up, six patients developed an aGVHD episode; in five of them, this event fitted with a modification of the TCR profile. Eleven patients achieved PCR-negativity during follow-up. In the 90% of them, the appearance of a new predominant TCR peak was concomitant to the disappearance of the IgH clone. These results suggest that different T gamma/delta populations would sustain GVM and GVH effects after non-myeloablative allogeneic transplant.
Department of Oncology, Transplant and Advances in Medicine, Section of Hematology, University of Pisa, Ospedale S. Chiara, Via Roma, 56, 56100 PISA, Italy. s.galimberti@med.unipi.it