GENE-MARKING AND HEMATOPOIETIC STEM-CELL TRANSPLANTATION

Gene transfer has allowed a number of biological issues in haematopoie tic stem cell transplantation to be addressed. Gene-marking studies ha ve shown that residual malignant cells in infused marrow may contribut e to relapse in acute myeloid leukaemia, neuroblastoma and chronic mye loid leukaemia. Double gene-marking techniques with distinguishable re troviral vectors are being used to compare purging techniques and the reconstitution of different sources of stem cells, In allogeneic bone- marrow transplantation, gene-marking has demonstrated that adoptively transferred cytotoxic T cells can persist and reconstitute antiviral i mmunity.