title: Monitoring of hematopoietic chimerism after transplantation for pediatric myelodysplastic syndrome: real-time or conventional short tandem repeat PCR in peripheral blood or bone marrow?
abstract: Quantitative real-time PCR (qPCR) has been proposed as a highly sensitive method for monitoring hematopoietic chimerism and may serve as a surrogate marker for the detection of minimal residual disease minimal residual disease in myelodysplastic syndrome (MDS), until specific methods of detection become available. Because a systematic comparison of the clinical utility of qPCR with the gold standard short tandem repeat (STR)-PCR has not been reported, we retrospectively measured chimerism by qPCR in 54 children transplanted for MDS in a previous study. Results obtained by STR-PCR in the initial study served as comparison. Because the detection limit of qPCR was sufficiently low to detect an autologous background, we defined the sample as mixed chimera if the proportion of recipient-derived cells exceeded .5%. The true positive rates were 100% versus 80% (qPCR versus STR-PCR, not significant), and mixed chimerism in most cases was detected earlier by qPCR than by STR-PCR (median, 31 days) when chimerism was quantified concurrently in peripheral blood and bone marrow. Both methods revealed a substantial rate of false positives (22.7% versus 13.6%, not significant), indicating the importance of serial testing of chimerism to monitor its progression. Finally, we propose criteria for monitoring chimerism in pediatric MDS with regard to the subtypes, specimens, PCR method, and timing of sampling.
authors.affiliation: Division for Stem Cell Transplantation and Immunology, Department for Children and Adolescents, University Hospital, Goethe University, Frankfurt/Main, Germany. Electronic address: andre.willasch@kgu.de.
authors.forename: Andre M
authors.initials: AM
authors.lastname: Willasch
authors.affiliation: Division for Stem Cell Transplantation and Immunology, Department for Children and Adolescents, University Hospital, Goethe University, Frankfurt/Main, Germany.
authors.forename: Hermann
authors.initials: H
authors.lastname: Kreyenberg
authors.affiliation: Medizinische Klinik und Poliklinik I, Universitätsklinikum Carl Gustav Carus der Technischen Universität, Dresden, Germany.
authors.forename: Nona
authors.initials: N
authors.lastname: Shayegi
authors.affiliation: Division for Stem Cell Transplantation and Immunology, Department for Children and Adolescents, University Hospital, Goethe University, Frankfurt/Main, Germany.
authors.forename: Eva
authors.initials: E
authors.lastname: Rettinger
authors.affiliation: Division for Stem Cell Transplantation and Immunology, Department for Children and Adolescents, University Hospital, Goethe University, Frankfurt/Main, Germany.
authors.forename: Vida
authors.initials: V
authors.lastname: Meyer
authors.affiliation: Division for Stem Cell Transplantation and Immunology, Department for Children and Adolescents, University Hospital, Goethe University, Frankfurt/Main, Germany.
authors.forename: Marion
authors.initials: M
authors.lastname: Zabel
authors.affiliation: Children's University Hospital, University of Tuebingen, Tuebingen, Germany.
authors.forename: Peter
authors.initials: P
authors.lastname: Lang
authors.affiliation: Department of Pediatric Hematology and Oncology, University Hospital, Essen, Germany.
authors.forename: Bernhard
authors.initials: B
authors.lastname: Kremens
authors.affiliation: Department of Pediatric Oncology, Hematology and Clinical Immunology, Medical Faculty, Center of Child and Adolescent Health, Heinrich-Heine-University, Duesseldorf, Germany.
authors.forename: Roland
authors.initials: R
authors.lastname: Meisel
authors.affiliation: Division of Pediatric Hematology and Oncology, Department of Pediatrics and Adolescent Medicine, University Medical Center, Freiburg, Germany.
authors.forename: Brigitte
authors.initials: B
authors.lastname: Strahm
authors.affiliation: Pediatric Hematology and Oncology, University Children's Hospital Muenster, Muenster, Germany.
authors.forename: Claudia
authors.initials: C
authors.lastname: Rossig
authors.affiliation: Department of Pediatrics, Jena University Hospital, Jena, Germany.
authors.forename: Bernd
authors.initials: B
authors.lastname: Gruhn
authors.affiliation: Division for Stem Cell Transplantation and Immunology, Department for Children and Adolescents, University Hospital, Goethe University, Frankfurt/Main, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Klingebiel
authors.affiliation: Division of Pediatric Hematology and Oncology, Department of Pediatrics and Adolescent Medicine, University Medical Center, Freiburg, Germany.
authors.forename: Charlotte M
authors.initials: CM
authors.lastname: Niemeyer
authors.affiliation: Division for Stem Cell Transplantation and Immunology, Department for Children and Adolescents, University Hospital, Goethe University, Frankfurt/Main, Germany.
authors.forename: Peter
authors.initials: P
authors.lastname: Bader
mesh_terms: D000293:Adolescent; D064591:Allografts; D001853:Bone Marrow; D002648:Child; D002675:Child, Preschool; D005260:Female; D018380:Hematopoietic Stem Cell Transplantation; D006801:Humans; D007223:Infant; D008297:Male; D008991:Monitoring, Physiologic / Q000379:methods*; D009190:Myelodysplastic Syndromes / Q000097:blood* / Q000628:therapy*; D060888:Real-Time Polymerase Chain Reaction; D018183:Transplantation Chimera / Q000097:blood*
keywords: Allogeneic SCT; Chimerism; Minimal residual disease; Pediatric MDS; Real-time PCR