| 摘要 |
Patients who develop increased numbers of gamma delta + cytotoxic T lymphocytes 2-6 months after allogeneic bone marrow transplantation are less likely to relapse than those who do not. The gamma delta + T cells isolated from blood of patients with increased gamma delta + T cells are CD3+CD4-CD8-CD57+, cytolytic to K562 cells, and express the V delta 1 T cell receptor phenotype. Similar gamma delta + T cells can be generated in vitro by culture of donor mononuclear cells which are enriched for gamma delta + T cells by immunomagnetic depletion of depleted of CD4+ and CD8+ cells. This gamma delta -enriched cell preparation was cultured on a combination of immobilized pan- delta monoclonal antibody and irradiated recipient B cell leukemia. After four weeks, the cultures were almost exclusively V delta 1+CD3+CD4-CD8- cells that co-expressed activation-associated antigens CD69, CD25, and HLA-DR. Furthermore, they were cytolytic against the primary leukemia obtained from the recipient and lymphoblastic leukemia cell lines, yet had minimal cytotoxicity against normal donor-derived mononuclear cells or myeloid leukemia cell lines. These observations suggest that donor-derived cytotoxic gamma delta + T cells can be generated in vitro, and may provide therapeutic potential for prevention of disease relapse. |
