Prognostic value of mixed Chimerism in assessment of relapse risk after BMT

• Published in: Genes and immunity Vol. 6; p. S73
• Main Authors: Stingl, K, Grubic, Z, Cecuk-Jelicic, E, Zunec, R, Serventi, R, Labar, B, Kerhin-Brkljacic, V
• Format: Journal Article
• Language: English
• Published: 01.04.2005
• ISSN: 1466-4879

Mixed chimerism (MC) is a state in which there is a presence of both recipient and donor haematopoietic cells and is frequently observed after bone marrow transplantation (BMT). In this study we monitored MC in the group of 36 patients suffering from various haematological disorders. All of them underwent classical conditioning regimen (31 patients for related BMT and 5 patients for unrelated BMT). DNA was isolated from peripheral blood and samples were PCR amplified for 5 STR loci (TH01, VWA31, FES/FPS, F13A01, and SE33) and for one VNTR locus (D1S80). Samples were run on a 6% polyacrylamide gel in an automated ALFexpress sequencer. In all 36 donor-recipient pairs we found differences for at least two STR loci. MC was detected in a total of eighteen patients: 4 cases of unrelated BMT and 14 cases with related sibling donor. In 11 cases MC was detected in early period after BMT but was soon followed by full donor chimerism (FDC). In five cases MC appeared after FDC was established and was predictive for the relapse. One patient showed alternating MC and FDC but at the end he showed only recipient cells (RC) and graft rejection. In conclusion, the PCR-STR analysis is a highly informative, fast and simple screening method for monitoring chimerism in BMT program. Results lead us to conclude that sequential follow-up of chimerism status provides crucial information on clinical status of patients.