Clinical Utility of Quantitative PCR for Chimerism and Engraftment Monitoring after Allogeneic Stem Cell Transplantation for Hematologic Malignancies Müberra Ahci, Karin Stempelmann, Ulrike Buttkereit, Pietro Crivello, Mirko Trilling, Andreas Heinold, Nina Kristin Steckel, Michael Koldehoff, Peter A. Horn, Dietrich W. Beelen, Katharina Fleischhauer Biology of Blood and Marrow Transplantation Volume 23, Issue 10, Pages 1658-1668 (October 2017) DOI: 10.1016/j.bbmt.2017.05.031 Copyright © 2017 The American Society for Blood and Marrow Transplantation Terms and Conditions
Figure 1 Kinetics of engraftment monitored by STR and qPCR. Shown are HC results obtained by STR (top) or qPCR (bottom) on longitudinal follow-up samples of example patients (Table 2). BM and PB samples are indicated as red and black dots, respectively. The HC positivity threshold of 1% and .1% for STR and qPCR, respectively, is indicated as dotted red line in the relevant plots in A and B. (A) Normal engraftment kinetics in 2 example patients. Note that isolated positive results in qPCR were obtained only on BM samples in the early post-SCT period. (B) Delayed engraftment kinetics in 2 example patients. Note that in both patients, decreasing mixed chimerism was observed as of day 100 post-SCT. (C) PMC in 2 example patients. Both patients received DLI (shaded area), with reversion to full donor HC within 196 and 296 days, respectively, as documented by qPCR. In 1 patient (patient 2738, left panels), PMC onset was closely preceded by CMV reactivation (arrow). Biology of Blood and Marrow Transplantation 2017 23, 1658-1668DOI: (10.1016/j.bbmt.2017.05.031) Copyright © 2017 The American Society for Blood and Marrow Transplantation Terms and Conditions
Figure 1 Kinetics of engraftment monitored by STR and qPCR. Shown are HC results obtained by STR (top) or qPCR (bottom) on longitudinal follow-up samples of example patients (Table 2). BM and PB samples are indicated as red and black dots, respectively. The HC positivity threshold of 1% and .1% for STR and qPCR, respectively, is indicated as dotted red line in the relevant plots in A and B. (A) Normal engraftment kinetics in 2 example patients. Note that isolated positive results in qPCR were obtained only on BM samples in the early post-SCT period. (B) Delayed engraftment kinetics in 2 example patients. Note that in both patients, decreasing mixed chimerism was observed as of day 100 post-SCT. (C) PMC in 2 example patients. Both patients received DLI (shaded area), with reversion to full donor HC within 196 and 296 days, respectively, as documented by qPCR. In 1 patient (patient 2738, left panels), PMC onset was closely preceded by CMV reactivation (arrow). Biology of Blood and Marrow Transplantation 2017 23, 1658-1668DOI: (10.1016/j.bbmt.2017.05.031) Copyright © 2017 The American Society for Blood and Marrow Transplantation Terms and Conditions
Figure 2 HC kinetics of STR and qPCR in relapse patients. BM samples are indicated as red and black dots, respectively. The HC positivity threshold of 1% and .1% for STR and qPCR, respectively, is indicated as dotted red line in the relevant plots. (A) STR (left) and qPCR (right) HC results on a total of 71 (53 PB, 18 BM) samples from 8 informative relapses. Thirty-three of these samples were drawn in the 6 months prerelapse (11 PB and 2 BM < day 90, 16 PB and 4 BM between days 90 and 180), and the remaining 38 samples (26 PB and 12 BM) more than 180 days before relapse onset. Note the striking increase in positive qPCR on PB in samples < 180 days (23/27) compared with >180 days (1/26) before relapse. (B) Longitudinal HC follow-up in the 6 months before relapse in 2 example patients (Table 2) by STR (top) or qPCR (bottom). Note that relapse was predicted by sustained positivity in qPCR both on BM and PB, whereas positivity in STR prerelapse was sporadic and mainly in BM. Both patients received DLIs to prevent relapse based on positivity in MRD or STR on sorted CD34+ cells (not shown). The inefficacy of DLI to prevent relapse was shown by lack of reversion to full donor chimerism prerelapse by qPCR but not by STR in both patients. (C) Longitudinal HC follow-up of relapse treatment by chemotherapy and DLI in 2 example patients (Table 2) by STR (top) or qPCR (bottom). In patient 2920, samples were available also prerelapse and showed sustained positivity of qPCR but not STR in the 6 months before relapse. In this patient, consolidation of remission by DLI after postrelapse chemotherapy was demonstrated by full donor HC also in qPCR. For patient 2265, samples were available only after induction of remission by chemotherapy and showed low levels of mixed HC in qPCR but not STR, which converted to full donor HC 126 days after DLI. Biology of Blood and Marrow Transplantation 2017 23, 1658-1668DOI: (10.1016/j.bbmt.2017.05.031) Copyright © 2017 The American Society for Blood and Marrow Transplantation Terms and Conditions
Figure 2 HC kinetics of STR and qPCR in relapse patients. BM samples are indicated as red and black dots, respectively. The HC positivity threshold of 1% and .1% for STR and qPCR, respectively, is indicated as dotted red line in the relevant plots. (A) STR (left) and qPCR (right) HC results on a total of 71 (53 PB, 18 BM) samples from 8 informative relapses. Thirty-three of these samples were drawn in the 6 months prerelapse (11 PB and 2 BM < day 90, 16 PB and 4 BM between days 90 and 180), and the remaining 38 samples (26 PB and 12 BM) more than 180 days before relapse onset. Note the striking increase in positive qPCR on PB in samples < 180 days (23/27) compared with >180 days (1/26) before relapse. (B) Longitudinal HC follow-up in the 6 months before relapse in 2 example patients (Table 2) by STR (top) or qPCR (bottom). Note that relapse was predicted by sustained positivity in qPCR both on BM and PB, whereas positivity in STR prerelapse was sporadic and mainly in BM. Both patients received DLIs to prevent relapse based on positivity in MRD or STR on sorted CD34+ cells (not shown). The inefficacy of DLI to prevent relapse was shown by lack of reversion to full donor chimerism prerelapse by qPCR but not by STR in both patients. (C) Longitudinal HC follow-up of relapse treatment by chemotherapy and DLI in 2 example patients (Table 2) by STR (top) or qPCR (bottom). In patient 2920, samples were available also prerelapse and showed sustained positivity of qPCR but not STR in the 6 months before relapse. In this patient, consolidation of remission by DLI after postrelapse chemotherapy was demonstrated by full donor HC also in qPCR. For patient 2265, samples were available only after induction of remission by chemotherapy and showed low levels of mixed HC in qPCR but not STR, which converted to full donor HC 126 days after DLI. Biology of Blood and Marrow Transplantation 2017 23, 1658-1668DOI: (10.1016/j.bbmt.2017.05.031) Copyright © 2017 The American Society for Blood and Marrow Transplantation Terms and Conditions