AUTHOR=Li Zhipeng , Wang Jing , Deng Lei , Liu Ximin , Kong Fanjun , Zhao Yuerong , Hou Yixi , Zhou Fang 

TITLE=The predictive value of T-cell chimerism for disease relapse after allogeneic hematopoietic stem cell transplantation

JOURNAL=Frontiers in Immunology

VOLUME=15

YEAR=2024

URL=https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2024.1382099

DOI=10.3389/fimmu.2024.1382099

ISSN=1664-3224

ABSTRACT=<sec><title>Introduction</title><p>Chimerism is closely correlated with disease relapse after allogeneic hematopoietic stem cell transplantation (allo-HSCT). However, chimerism rate is dynamic changes, and the sensitivity of different chimerism requires further research.</p></sec><sec><title>Methods</title><p>To investigate the predictive value of distinct chimerism for relapse, we measured bone marrow (BM), peripheral blood (PB), and T-cell (isolated from BM) chimerism in 178 patients after allo-HSCT.</p></sec><sec><title>Results</title><p>Receiver operating characteristic (ROC) curve showed that T-cell chimerism was more suitable to predict relapse after allo-HSCT compared with PB and BM chimerism. The cutoff value of T-cell chimerism for predicting relapse was 99.45%. Leukemia and myelodysplastic syndrome (MDS) relapse patients’ T-cell chimerism was a gradual decline from 2 months to 9 months after allo-HSCT. Higher risk of relapse and death within 1 year after allo-HSCT. The T-cell chimerism rates in remission and relapse patients were 99.43% and 94.28% at 3 months after allo-HSCT (<italic>P</italic> = 0.009), 99.31% and 95.27% at 6 months after allo-HSCT (<italic>P</italic> = 0.013), and 99.26% and 91.32% at 9 months after allo-HSCT (<italic>P</italic> = 0.024), respectively. There was a significant difference (<italic>P</italic> = 0.036) for T-cell chimerism between early relapse (relapse within 9 months after allo-HSCT) and late relapse (relapse after 9 months after allo-HSCT) at 2 months after allo-HSCT. Every 1% increase in T-cell chimerism, the hazard ratio for disease relapse was 0.967 (95% CI: 0.948–0.987, <italic>P</italic>&lt;0.001).</p></sec><sec><title>Discussion</title><p>We recommend constant monitoring T-cell chimerism at 2, 3, 6, and 9 months after allo-HSCT to predict relapse.</p></sec>