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.

Bone Marrow Chimerism Detection Using Next Generation Sequencing Based on Single Nucleotide Polymorphisms Following Liver Transplantation: Comparison With Short Tandem Repeat-PCR

No abstract available.

Prevalence of chimerism after non-myeloablative hematopoietic stem cell transplantation / Prevalência do quimerismo após transplante de células hematopoiéticas não-mieloablativo

Context and objective: Non-myeloablative hematopoietic stem cell transplantation (NMA-HSCT) is performed in onco-hematological patients who cannot tolerate ablative conditioning because of older age or comorbidities. This approach does not completely eliminate host cells and initially results in mixed chimerism. Long-term persistence of mixed chimerism results in graft rejection and relapse. Involvement of graft-versus-host disease is concomitant with complete chimerism and graft-versus-tumor effect. The aim of this study was to evaluate the prevalence of chimerism in onco-hematological patients who underwent NMA-HSCT. Desingn and setting: Observational clinical study on chimerism status after human leukocyte antigen-identical NMA-HSCT at the Discipline of Hematology and Hemotherapy of Universidade Federal de São Paulo. Methods: We sequentially analyzed the amplification of APO-B, D1S80, DxS52, FVW, 33.6, YNZ-2 and H-ras primers using variable number of tandem repeats (VNTR) on 17 pairs and fluorescent in situ hybridization (FISH) with the XY probe and SRY primer on 13 sex-unmatched pairs. RESULTS: The informativeness of the primers using VNTR was 60 percent for APO-B, 75 percent D1S80, 36 percent DxS52, 14 percent FVW, 40 percent YNZ-22 and 16 percent H-ras. The SRY primer was informative in female receptors with male donors. The XY-FISH method was informative in 100 percent of the sex-unmatched pairs. Conclusion: These methods were sensitive and informative. In VNTR, the association of APO-B with D1S80 showed 88 percent informativeness. The quantitative FISH method was more sensitive, but had the disadvantage of only being used for sex-unmatched pairs.

Contexto e objetivo: O transplante de células hematopoiéticas não-mieloablativo é realizado em pacientes com doenças onco-hematológicas que não suportam condicionamentos ablativos devido à elevada idade ou ao acometimento por comorbidades. Esta abordagem não elimina completamente as células do hospedeiro, resultando, inicialmente, em quimerismo misto. A persistência do quimerismo misto na evolução de longo prazo resulta na rejeição ao enxerto e recaída. O acometimento pela doença do enxerto contra hospedeiro é concomitante ao quimerismo completo e ao efeito enxerto versus tumor. O objetivo deste estudo foi avaliar a prevalência do quimerismo em doenças onco-hematológicas tratadas com o transplante não-mieloablativo de células hematopoiéticas. Tipo de estudo e local: Estudo clínico observacional do estado de quimerismo após transplante antígenos leucocitários humanos-idêntico não-mieloabaltivo realizado na Disciplina de Hematologia e Hemoterapia da Universidade Federal de São Paulo. Métodos: Analisamos sequencialmente a amplificação dos primers APO-B, D1S80, DxS52, FVW, 33,6, YNZ-22, H-ras pelo VNTR (variable number of tandem repeats) em 17 pares e FISH (fluorescent in situ hybridization) pela sonda XY e do primer SRY em 13 pares de não relacionados a sexo. Resultado: A informatividade dos primers pelo VNTR foi de 60 por cento para APO-B; 75 por cento D1S80; 36 por cento DxS52; 14 por cento FVW; 40 por cento YNZ-22 e 16 por cento H-ras. O primer SRY foi informativo em receptores femininos com doadores masculinos. O método XY-FISH foi informativo em 100 por cento dos pares de não relacionado a sexo. Conclusão: Estes métodos foram sensíveis e informativos. No VNTR, a associação do APO-B com D1S80 mostrou 88 por cento de informatividade. O FISH, método quantitativo, foi mais sensível, porém com desvantagem de ser usado somente nos pares não relacionados a sexo.

Importancia del estudio del quimerismo en el trasplante alogénico de médula ósea / Importance of the study of chimerism in the allogeneic bone marrow transplantation

Desde que se comenzó a realizar el trasplante hematopoyético se reconoció la importancia de conocer el establecimiento de quimerismo. El presente trabajo actualiza los conceptos de quimerismo, su clasificación y las diferentes vías para su determinación. Se destaca como la más recomendada, la amplificación de zonas altamente polimórficas en el ADN por la técnica de la reacción en cadena de la polimerasa. La utilización de esta técnica ha permitido realizar estudios de la evolución de la quimera, relacionar el grado de quimerismo establecido con el comportamiento del injerto y de la enfermedad de injerto contra hospedero en los diferentes regímenes de acondicionamiento. También ha posibilitado la detección precoz de la recaída en los pacientes trasplantados y la administración oportuna de inmunoterapia adicional. Finalmente, se presentan las recomendaciones de la Sociedad Americana de Trasplante de Sangre y Médula Ósea para estandarizar el estudio del quimerismo en los diferentes centros de tratamiento

Clinical correlations of peripheral blood microchimerism after liver transplantation

The aim of this study was to evaluate microchimerism after human liver transplantation (LT). This study included 13 female recipients who received hepatic allograft from male donors at Asan Medical Center. A nested PCR specific for Y-chromosome gene (DYZ3) was used to analyze the small number of male cells in the peripheral blood mononuclear cells of the female recipients. Microchimerism was observed in 6 of 13 recipients and 16 out of 35 samples. Only 3 patients showed microchimerism 3 months after LT. There was no statistical difference between the presence of microchimerism and clinical findings such as type of donor, type of immunosuppression, episode of rejection and age of recipient. This study did not show any clinical relevance of microchimerism and further larger study are needed to confirm the results.

Clinical correlations of peripheral blood microchimerism after liver transplantation

The aim of this study was to evaluate microchimerism after human liver transplantation (LT). This study included 13 female recipients who received hepatic allograft from male donors at Asan Medical Center. A nested PCR specific for Y-chromosome gene (DYZ3) was used to analyze the small number of male cells in the peripheral blood mononuclear cells of the female recipients. Microchimerism was observed in 6 of 13 recipients and 16 out of 35 samples. Only 3 patients showed microchimerism 3 months after LT. There was no statistical difference between the presence of microchimerism and clinical findings such as type of donor, type of immunosuppression, episode of rejection and age of recipient. This study did not show any clinical relevance of microchimerism and further larger study are needed to confirm the results.

Trasplante de medula osea en leucemia mieloide cronica / Bone marrow transplantation in chronic myelogenous leukemia

La Leucemia Mieloide Crónica (LCM) es un proceso oncohematológico caracterizado por una proliferación clonal que afecta a la célula hematopoyética primitiva. Un 95 por ciento de pacientes presenta una alteración citogenética característica conocida como Cromosoma Philadelphia (Ph1), producto de una traslocación cromosómica 9:22, que da lugar a un gen hídrido BCR/ABL. Diecinueve pacientes con LMC recibieron Trasplante Alogeneico de Médula Osea (TMO), 9 fueron de sexo femenino y 10 de sexo masculino. La média de edad fue de 32 años (rango 9-47); 15 de los pacientes estaban en fase crónica (FC) y 4 en fase acelerada (FA). Todos los pacientes al momento del diagnóstico fueron Ph1+, BCR/ABL+. El régimen de acondicionamiento consistió en Busulflán y Ciclofosfamida, con el agregado de Etoposido en los pacientes en FA. La profilaxis de EICH se efectuó con Ciclosporina A, Metotrexato y Metilprednisona en 17 pacientes y con las 2 primeras drogas en 2 pacientes. La traslocación 922 se estudió mediante técnica de RT-PCR, con empleo de las sondas NB1+, Abl3, B2A, CA3 y A2. La sensibilidad del método fue de 1 x 10(-6). De 19 pacientes que ingresaron al protocolo, 14 permanecen vivos y en remisión clínica, hematológica y citogenética (Ph, negativo); 3 pacientes fallecieron de EICH agudo, 1 de fallo de "angraftment" y 1 de síndrome urémico hemolítico. De 4 pacientes trasplantados en FA, 3 están vivos y en remisión completa. Los pacientes con LMC trasplantados presentaron una sobrevida del 74 por ciento con un seguimiento medio de 655 días. El quimerismo hematopoyético completo se demostró en 16 pacientes, mediante el estudio de 3 loci, D1S80, APO B y D17S30. No se encontró ninguna relación entre la presencia post TMO del híbrido BCR/ABL (RT.PCR) y la recaída de la enfermedad; la presencia de EICH agudo y/o crónico no tuvo influencia entre la positividad del BCR/ABL. El TMO ha demostrado se en nuestra experiencia la única alternativa terapéutica para la LMC con obtención de remisión completa, clínica, hematológica y citogenética, con una sobrevida media del 74 por ciento comparable a la de centros internacionales de trasplante.