1. ¹Department of Cellular Transplantation Biology, Kanazawa University Graduate School of Medicine, Kanazawa, Japan
2. ²Department of Pediatrics, Kanazawa University Graduate School of Medicine, Kanazawa, Japan
3. ³Laboratory of Viral Oncology, Aichi Cancer Center Research Institute, Nagoya, Japan

Correspondence: Dr A Takami, Department of Cellular Transplantation Biology, Kanazawa University Graduate School of Medicine, 13-1 Takaramachi, Kanazawa 920-8641, Japan. E-mail: takami@med3.m.kanazawa-u.ac.jp

Received 20 October 2003; Accepted 13 April 2004; Published online 23 August 2004.

Abstract

The immune system of females is capable of recognizing and reacting against the male-specific minor histocompatibility antigen (mHA), HY. Thus, cytotoxic T-lymphocytes (CTLs) recognizing this antigen may be useful in eradicating leukemic cells of a male patient if they can be generated in vivo or in vitro from a human leukocyte antigen (HLA)-identical female donor. The HLA-A^*0201-restricted HY antigen, FIDSYICQV, is a male-specific mHA. Using HLA-A2/HY peptide tetrameric complexes, we reveal a close association between the emergence of HY peptide-specific CD8⁺ T cells in peripheral blood and molecular remission of relapsed BCR/ABL⁺ chronic myelogenous leukemia in lymphoid blast crisis in a patient who underwent female-to-male transplantation. Assessment of intracellular cytokine levels identified T cells that produce interferon- in response to the HY peptide during the presence of HY tetramer-positive T cells. These results indicate that transplant with allogeneic HY-specific CTLs has therapeutic potential for relapsed leukemia, and that expansion of such T cells may be involved in the development of a graft-versus-leukemia response against lymphoblastic leukemia cells.