Strategy Optimization and Clinical Analyze of Multiple Nucleotide Polymorphism Analysis in the Chimerism Detection after Allogeneic Hematopoietic Stem Cell Transplantation / 中国实验血液学杂志

AbstractObjective: To investigate the sample selection, result correction and clinical application value of multi nucleotide polymorphism chimerism detection method based on Next-generation sequencing.@*METHODS@#The chimerism samples from November 2018 to June 2020 were collected, and Pearson correlation coefficient (r) was used to analyze the consistency of bone marrow and peripheral blood results detected by MNPseq; according to the different information integrity before transplantation, the calibration model was constructed to analyze the correction value of the micro chimerism results in each model; the clinical results were retrospectively analyzed to verify the reliability and practicability of chimerism results correction and the clinical value of MNPseq method.@*RESULTS@#The results of bone marrow and peripheral blood chimerism detected by MNPseq method were consistent with each other and showed significant correlation (r=0.985, P<0.01). The three groups of calibration models were constructed according to different pre-transplant information. For the no donor and pre-transplant patients information group, the correction value was 1%; while for the group with pre-transplant patients and without donor information, 0.61% of the chimerism rate and 13 heterotopic points were used as the correction value; 0.26% of the chimerism rate and 21.57% of the heterotopic points were used as the correction value for the group with pre-transplantation patients and donor information. After correction, the number of the patients with incomplete chimerism decreased from 276 (74.19%) to 141 (37.91%) (P<0.01). Among 18 (18/141, 12.77%) patients with incomplete chimerism, the results of MNPseq in the patients were 25-39 days earlier than those in STR and flow MRD, and the result showed statistical significance.@*CONCLUSION@#MNPseq method can be used to monitor chimerism with peripheral blood instead of bone marrow samples, and the results can be corrected to detect the changes of graft status in vivo in a more timely manner.

Application of multiple nucleotide polymorphism analysis in chimerism detection after allogeneic hematopoietic stem cell transplantation / 中华血液学杂志

Objective: To establish a new method for chimerism analysis after allogeneic hematopoietic stem cell transplantation by using multiple nucleotide polymorphism sequencing (MNPseq) , and to explore its feasibility and superiority. Methods: One hundred MNP fragments were screened and chimeric analysis was performed by high-throughput sequencing technology. The accuracy and sensitivity of the method were verified by simulating chimeric samples and post-transplant samples and comparing them with short tandem repeat (STR) analysis, fusion gene quantitative detection and flow cytometry for minimal residual disease. Results: The accuracy and sensitivity of MNPseq were better than those of STR, in which the sensitivity could reach 0.01%, about 100 times more sensitive than STR. MNPseq could further distinguish 42 STR fully chimeric samples, and after corrected by cutoff value, it was correlated with the quantitative detection of fusion gene. MNPseq could correct false positive of STR caused by the shadow peak, and could be used to detect chimeric samples lacking pre-transplant information from donors and recipients. Conclusion: MNPseq analysis based on high-throughput sequencing is a more accurate and sensitive chimerism detection method, and it solves the problem that chimerism cannot be detected due to the lack of pre-transplant information, which has extremely high clinical application value.

Application of multiple nucleotide polymorphism analysis in chimerism detection after allogeneic hematopoietic stem cell transplantation / 中华血液学杂志

Objective@#To establish a new method for chimerism analysis after allogeneic hematopoietic stem cell transplantation by using multiple nucleotide polymorphism sequencing (MNPseq) , and to explore its feasibility and superiority.@*Methods@#One hundred MNP fragments were screened and chimeric analysis was performed by high-throughput sequencing technology. The accuracy and sensitivity of the method were verified by simulating chimeric samples and post-transplant samples and comparing them with short tandem repeat (STR) analysis, fusion gene quantitative detection and flow cytometry for minimal residual disease.@*Results@#The accuracy and sensitivity of MNPseq were better than those of STR, in which the sensitivity could reach 0.01%, about 100 times more sensitive than STR. MNPseq could further distinguish 42 STR fully chimeric samples, and after corrected by cutoff value, it was correlated with the quantitative detection of fusion gene. MNPseq could correct false positive of STR caused by the shadow peak, and could be used to detect chimeric samples lacking pre-transplant information from donors and recipients.@*Conclusion@#MNPseq analysis based on high-throughput sequencing is a more accurate and sensitive chimerism detection method, and it solves the problem that chimerism cannot be detected due to the lack of pre-transplant information, which has extremely high clinical application value.