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Zhang L, Deeb G, Deeb KK, Vale C, Peker Barclift D, Papadantonakis N. Measurable (Minimal) Residual Disease in Myelodysplastic Neoplasms (MDS): Current State and Perspectives. Cancers (Basel) 2024; 16:1503. [PMID: 38672585 PMCID: PMC11048433 DOI: 10.3390/cancers16081503] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2024] [Revised: 04/08/2024] [Accepted: 04/10/2024] [Indexed: 04/28/2024] Open
Abstract
Myelodysplastic Neoplasms (MDS) have been traditionally studied through the assessment of blood counts, cytogenetics, and morphology. In recent years, the introduction of molecular assays has improved our ability to diagnose MDS. The role of Measurable (minimal) Residual Disease (MRD) in MDS is evolving, and molecular and flow cytometry techniques have been used in several studies. In this review, we will highlight the evolving concept of MRD in MDS, outline the various techniques utilized, and provide an overview of the studies reporting MRD and the correlation with outcomes.
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Affiliation(s)
- Linsheng Zhang
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - George Deeb
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Kristin K. Deeb
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Colin Vale
- Department of Hematology and Medical Oncology, Winship Cancer Institute of Emory University, Atlanta, GA 30322, USA
| | - Deniz Peker Barclift
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Nikolaos Papadantonakis
- Department of Hematology and Medical Oncology, Winship Cancer Institute of Emory University, Atlanta, GA 30322, USA
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Akkari Y, Baughn LB, Kim A, Karaca E, Raca G, Shao L, Mikhail FM. Section E6.1-6.6 of the American College of Medical Genetics and Genomics (ACMG) Technical Laboratory Standards: Cytogenomic studies of acquired chromosomal abnormalities in neoplastic blood, bone marrow, and lymph nodes. Genet Med 2024; 26:101054. [PMID: 38349293 DOI: 10.1016/j.gim.2023.101054] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Accepted: 12/08/2023] [Indexed: 04/09/2024] Open
Abstract
Cytogenomic analyses of acquired clonal chromosomal abnormalities in neoplastic blood, bone marrow, and/or lymph nodes are instrumental in the clinical management of patients with hematologic neoplasms. Cytogenetic analyses assist in the diagnosis of such disorders and can provide important prognostic information. Furthermore, cytogenetic studies can provide crucial information regarding specific genetically defined subtypes of these neoplasms that may have targeted therapies. At time of relapse, cytogenetic analysis can confirm recurrence of the original neoplasm, detect clonal disease evolution, or uncover a new unrelated neoplastic process. This section deals specifically with the technical standards applicable to cytogenomic studies of acquired clonal chromosomal abnormalities in neoplastic blood, bone marrow, and/or lymph nodes. This updated Section E6.1-6.6 supersedes the previous Section E6 in Section E: Clinical Cytogenetics of the American College of Medical Genetics and Genomics Technical Standards for Clinical Genetics Laboratories.
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Affiliation(s)
- Yassmine Akkari
- The Steve and Cindy Rasmussen Institute for Genomic Medicine, Nationwide Children's Hospital, Columbus, OH
| | - Linda B Baughn
- Division of Hematopathology, Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN
| | - Annette Kim
- Department of Pathology, University of Michigan, Ann Arbor, MI
| | - Ender Karaca
- Department of Pathology, Baylor University Medical Center, Dallas, TX; Texas A&M School of Medicine, Texas A&M University, Dallas, TX
| | - Gordana Raca
- Department of Pathology and Laboratory Medicine, Children's Hospital Los Angeles, Los Angeles, CA; Keck School of Medicine, University of Southern California, Los Angeles, CA
| | - Lina Shao
- Department of Pathology, University of Michigan, Ann Arbor, MI
| | - Fady M Mikhail
- Department of Genetics, University of Alabama at Birmingham, Birmingham, AL
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3
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Clarke SE, Fuller KA, Erber WN. Chromosomal defects in multiple myeloma. Blood Rev 2024; 64:101168. [PMID: 38212176 DOI: 10.1016/j.blre.2024.101168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Revised: 12/01/2023] [Accepted: 01/02/2024] [Indexed: 01/13/2024]
Abstract
Multiple myeloma is a plasma cell neoplasm driven by primary (e.g. hyperdiploidy; IGH translocations) and secondary (e.g. 1q21 gains/amplifications; del(17p); MYC translocations) chromosomal events. These are important to detect as they influence prognosis, therapeutic response and disease survival. Currently, cytogenetic testing is most commonly performed by interphase fluorescence in situ hybridisation (FISH) on aspirated bone marrow samples. A number of variations to FISH methodology are available, including prior plasma cell enrichment and incorporation of immunophenotypic plasma cell identification. Other molecular methods are increasingly being utilised to provide a genome-wide view at high resolution (e.g. single nucleotide polymorphism (SNP) microarray analysis) and these can detect abnormalities in most cases. Despite their wide application at diagnostic assessment, both FISH and SNP-array have relatively low sensitivity, limiting their use for identification of prognostically significant low-level sub-clones or for disease monitoring. Next-generation sequencing is increasingly being used to detect mutations and new FISH techniques such as by flow cytometry are in development and may address some of the current test limitations. Here we review the primary and secondary cytogenetic aberrations in myeloma and discuss the range of techniques available for their assessment.
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Affiliation(s)
- Sarah E Clarke
- School of Biomedical Sciences, The University of Western Australia (M504), Crawley, WA 6009, Australia; Department of Haematology, PathWest Laboratory Medicine WA, Fiona Stanley Hospital, Murdoch, WA 6150, Australia.
| | - Kathryn A Fuller
- School of Biomedical Sciences, The University of Western Australia (M504), Crawley, WA 6009, Australia.
| | - Wendy N Erber
- School of Biomedical Sciences, The University of Western Australia (M504), Crawley, WA 6009, Australia; PathWest Laboratory Medicine WA, Royal Perth Hospital, Perth, WA 6000, Australia.
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Chopra S, Dunham T, Syrbu SI, Karandikar NJ, Darbro BW, Holman CJ. Utility of Flow Cytometry and Fluorescence In Situ Hybridization in Follow-up Monitoring of Plasma Cell Myeloma. Am J Clin Pathol 2021; 156:198-204. [PMID: 33437993 DOI: 10.1093/ajcp/aqaa224] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
OBJECTIVES We sought to investigate the clinical utility of flow cytometry (FC) and fluorescence in situ hybridization (FISH) in the workup of myeloma. METHODS We retrospectively reviewed the reports of bone marrow biopsies received for myeloma evaluation between October 2015 and January 2019. RESULTS A total of 1,708 biopsy specimens from 469 myeloma patients (mean age, 64.5 years [SD, 9.3]; female, 41.4%) were reviewed. Both FC and FISH had comparable detection rates at the time of initial diagnosis (97.6% vs 98.8%) and for follow-up cases (28.6% vs 28.2%). FC and FISH results were concordant in 98.8% of the initial diagnosis cases and 89.6% of the follow-up cases. The FISH-positive (FISH+)/FC-negative (FC-) discordance and FISH-/FC+ discordance occurred among 81 (5.0%) and 87 (5.4%) follow-up cases. In comparison with all concordant cases, FISH+/FC- discordant cases were more likely to have received treatment with daratumumab (P < .05). CONCLUSIONS Plasma cell-enriched FISH and FC have comparable abnormal plasma cell detection rates, and approximately 10% of the follow-up cases have discordant FISH and FC results in which residual disease is detected by only one of these modalities. FISH testing should be considered for cases with negative FC, especially in patients who have received treatment with daratumumab or in cases in which there is concern about specimen adequacy.
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Affiliation(s)
| | - Timothy Dunham
- Stead Family Department of Pediatrics, University of Iowa Hospitals and Clinics, Iowa City
| | | | | | - Benjamin W Darbro
- Stead Family Department of Pediatrics, University of Iowa Hospitals and Clinics, Iowa City
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Ma ESK, Wang CLN, Wong ATC, Choy G, Chan TL. Target fluorescence in-situ hybridization (Target FISH) for plasma cell enrichment in myeloma. Mol Cytogenet 2016; 9:63. [PMID: 27532015 PMCID: PMC4986355 DOI: 10.1186/s13039-016-0263-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2016] [Accepted: 07/13/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Cytogenetic abnormalities are important prognostic markers in plasma cell myeloma (PCM) and detection is routinely performed by interphase fluorescence in-situ hybridization (FISH) with a panel of probes after enrichment of the plasma cells in the bone marrow specimen. Cell sorting by immunomagnetic beads and concurrent labeling of the cytoplasmic immunoglobulin are the usual enrichment methods. We present an alternative method of plasma cell enrichment termed Target FISH, which is an automated system that combines the images of May-Grünwald- Giemsa (MGG) staining and FISH study on the same plasma cell for analysis. RESULTS Our experience of Target FISH on 40 PCM patients was described. Briefly, plasma cells were MGG stained, image captured, de-stained, FISH probe hybridized and finally relocated for simultaneous analysis of morphology and FISH signal pattern. The FISH probe panel was TP53/CEP17, t(4;14) IGH/FGFR3, t(14;16) IGH/MAF and CKS1B(1q21)/CDKN2C(P18). Gain of 1q21 was the most common abnormality detected in 18 patients (45 %), to be followed by t(4;14) IGH/FGFR3 detected in 11 patients (27.5 %). Of note, 10 patients showed coexistence of both t(4;14) and 1q21 gain. Two patients showed del(17p)/TP53, one in association with t(4;14) and 1q gain while the other was stand alone. None of this patient cohort showed t(14;16) IGH/MAF. Using the critical binomial function, the normal cutoff FISH positive value for del(17p)/TP53 was 3.4 %, t(4;14) IGH/FGFR3 was 6.8 %, t(14;16) IGH/MAF was 5.6 % and +1q21 was 5.7 %. CONCLUSIONS The equipment cost notwithstanding, when compared with cell sorting, the total reagent cost was around 10 % lower in Target FISH. The total processing time was longer for Target FISH but manual fluorescence microscopy was no longer necessary. The main advantage of Target FISH was the complete certainty that the cytogenetic abnormality was detected in the cells of interest, and hence a more stringent analytical cutoff value might be considered. Optimization of the cell collection and slide preparation process upfront was required to accrue adequate target cells on each slide for analysis. Our experience suggested that Target FISH was applicable as a routine method of plasma cell enrichment in clinical diagnostic laboratories.
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Affiliation(s)
- Edmond S K Ma
- Division of Molecular Pathology, Department of Pathology, Hong Kong Sanatorium & Hospital, Clinical Pathology Laboratory, 1/F Li Shu Fan Block, 2 Village Road, Happy Valley, Hong Kong
| | - Candy L N Wang
- Division of Molecular Pathology, Department of Pathology, Hong Kong Sanatorium & Hospital, Clinical Pathology Laboratory, 1/F Li Shu Fan Block, 2 Village Road, Happy Valley, Hong Kong
| | - Anthony T C Wong
- Division of Molecular Pathology, Department of Pathology, Hong Kong Sanatorium & Hospital, Clinical Pathology Laboratory, 1/F Li Shu Fan Block, 2 Village Road, Happy Valley, Hong Kong
| | - Gigi Choy
- Division of Molecular Pathology, Department of Pathology, Hong Kong Sanatorium & Hospital, Clinical Pathology Laboratory, 1/F Li Shu Fan Block, 2 Village Road, Happy Valley, Hong Kong
| | - Tsun Leung Chan
- Division of Molecular Pathology, Department of Pathology, Hong Kong Sanatorium & Hospital, Clinical Pathology Laboratory, 1/F Li Shu Fan Block, 2 Village Road, Happy Valley, Hong Kong
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Mikhail FM, Heerema NA, Rao KW, Burnside RD, Cherry AM, Cooley LD. Section E6.1-6.4 of the ACMG technical standards and guidelines: chromosome studies of neoplastic blood and bone marrow-acquired chromosomal abnormalities. Genet Med 2016; 18:635-42. [PMID: 27124785 DOI: 10.1038/gim.2016.50] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Accepted: 03/01/2016] [Indexed: 12/30/2022] Open
Abstract
DISCLAIMER These American College of Medical Genetics and Genomics standards and guidelines are developed primarily as an educational resource for clinical laboratory geneticists to help them provide quality clinical laboratory genetic services. Adherence to these standards and guidelines is voluntary and does not necessarily ensure a successful medical outcome. These standards and guidelines should not be considered inclusive of all proper procedures and tests or exclusive of other procedures and tests that are reasonably directed to obtaining the same results. In determining the propriety of any specific procedure or test, the clinical laboratory geneticist should apply his or her own professional judgment to the specific circumstances presented by the individual patient or specimen. Clinical laboratory geneticists are encouraged to document in the patient's record the rationale for the use of a particular procedure or test, whether or not it is in conformance with these standards and guidelines. They also are advised to take notice of the date any particular guideline was adopted, and to consider other relevant medical and scientific information that becomes available after that date. It also would be prudent to consider whether intellectual property interests may restrict the performance of certain tests and other procedures.Cytogenetic analyses of hematological neoplasms are performed to detect and characterize clonal chromosomal abnormalities that have important diagnostic, prognostic, and therapeutic implications. At the time of diagnosis, cytogenetic abnormalities assist in the diagnosis of such disorders and can provide important prognostic information. At the time of relapse, cytogenetic analysis can be used to confirm recurrence of the original neoplasm, detect clonal disease evolution, or uncover a new unrelated neoplastic process. This section deals specifically with the standards and guidelines applicable to chromosome studies of neoplastic blood and bone marrow-acquired chromosomal abnormalities. This updated Section E6.1-6.4 has been incorporated into and supersedes the previous Section E6 in Section E: Clinical Cytogenetics of the 2009 Edition (Revised 01/2010), American College of Medical Genetics and Genomics Standards and Guidelines for Clinical Genetics Laboratories.Genet Med 18 6, 635-642.
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Affiliation(s)
- Fady M Mikhail
- Department of Genetics, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Nyla A Heerema
- Department of Pathology, The Ohio State University, Columbus, Ohio, USA
| | - Kathleen W Rao
- Department of Pediatrics, University of North Carolina, Chapel Hill, North Carolina, USA.,Department of Pathology, University of North Carolina, Chapel Hill, North Carolina, USA.,Deceased
| | - Rachel D Burnside
- Laboratory Corporation of America Holdings, Center for Molecular Biology and Pathology, Research Triangle Park, North Carolina, USA
| | - Athena M Cherry
- Department of Pathology, Stanford University School of Medicine, Stanford, California, USA
| | - Linda D Cooley
- Department of Pathology and Laboratory Medicine, Children's Mercy Hospital, University of Missouri Kansas City Medical School, Kansas City, Missouri, USA
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Ortega V, Mohamed G, Ehman W, Zhu M, Mendiola C, Velagaleti G. Optimal strategy for obtaining routine chromosome analysis by using negative fractions of CD138 enriched plasma cells. Cancer Genet 2015; 209:82-6. [PMID: 26797313 DOI: 10.1016/j.cancergen.2015.12.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2015] [Revised: 10/16/2015] [Accepted: 12/14/2015] [Indexed: 12/01/2022]
Abstract
Fluorescence in situ hybridization (FISH) is superior to routine chromosome analysis (RCA) in detecting important prognostic genetic abnormalities in plasma cell dyscrasia (PCD); however, its sensitivity is hampered due to paucity of plasma cells (PC) in whole bone marrow (BM). Studies showed that the abnormality detection rate in enriched plasma cells (EPC) is greater than unselected plasma cells (UPC), but purification techniques are limiting to only FISH when sample volumes are inadequate. Not performing RCA may compromise patient care since RCA is equally important for detecting non-PC related abnormalities when the diagnosis is undefined. To resolve this critical issue, we designed a study where an immuno-magnetic CD138 enriched positive selection was used for FISH while the negative fraction (NF) was used to retrieve other myeloid elements for RCA. Parallel FISH studies were performed using UPC and CD138 EPC, while karyotyping was achieved using whole BM and discarded myeloid elements from the NF. Results showed that the abnormality rate of EPC was doubled compared to UPC for FISH, and CA displayed 100% success rate using the NF. PCD related chromosome abnormalities were confined to whole BM while non-PCD related abnormalities were found in both whole BM and NF. Our results demonstrate the feasibility of using the NF for RCA.
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Affiliation(s)
- Veronica Ortega
- Department of Pathology, University of Texas Health Science Center, San Antonio, TX, USA
| | - Gihan Mohamed
- Department of Pathology, University of Texas Health Science Center, San Antonio, TX, USA
| | - William Ehman
- Department of Pathology, University of Texas Health Science Center, San Antonio, TX, USA
| | - Meiqing Zhu
- Department of Pathology, University of Texas Health Science Center, San Antonio, TX, USA
| | - Christina Mendiola
- Department of Pathology, University of Texas Health Science Center, San Antonio, TX, USA
| | - Gopalrao Velagaleti
- Department of Pathology, University of Texas Health Science Center, San Antonio, TX, USA.
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Wang W, Corrigan-Cummins M, Barber EA, Saleh LM, Zingone A, Ghafoor A, Costello R, Zhang Y, Kurlander RJ, Korde N, Roccaro AM, Ghobrial IM, Landgren O, Calvo KR. Aberrant Levels of miRNAs in Bone Marrow Microenvironment and Peripheral Blood of Myeloma Patients and Disease Progression. J Mol Diagn 2015; 17:669-78. [PMID: 26433312 DOI: 10.1016/j.jmoldx.2015.06.006] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2015] [Revised: 05/26/2015] [Accepted: 06/22/2015] [Indexed: 12/20/2022] Open
Abstract
The bone marrow (BM) microenvironment of multiple myeloma (MM) is reported to play a role in the biology of disease. In this study, we found that the extracellular BM microenvironment in MM contains a unique miRNA signature detectable by miRNA microarray and quantitative real-time PCR, which is partially represented in the peripheral blood. Eleven miRNAs were significantly decreased in both BM and serum of MM patients in comparison with controls. Evaluation of these miRNAs in plasma of a separate cohort of MM patients and controls confirmed significantly aberrant levels of let-7a, let-7b, let-7i, miR-15b, miR-16, and miR-20a in both serum and plasma. We then studied the myeloma precursor diseases and found that a subset of the MM miRNAs exhibited aberrant expression in monoclonal gammopathy of undetermined significance and smoldering myeloma. miRNA analysis of enriched CD138(+) plasma cells from MM and monoclonal gammopathy of undetermined significance found that most of the validated MM BM signature miRNAs were significantly decreased in MM plasma cells. Gene expression profiling indicated that multiple targets of the decreased miRNAs found increased expression in MM plasma cells, including ATF2, HRAS, HDAC4, TGFB1, TGFBR1, and mitogen-activated protein kinases. The findings suggest that these miRNAs are detectable in aberrant levels in the peripheral blood of patients with plasma cell proliferation and may play a role in aberrant plasma cell proliferation and disease progression.
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Affiliation(s)
- Weixin Wang
- Hematology Section, Department of Laboratory Medicine, National Institutes of Health Clinical Center, Bethesda, Maryland
| | - Meghan Corrigan-Cummins
- Hematology Section, Department of Laboratory Medicine, National Institutes of Health Clinical Center, Bethesda, Maryland
| | - Emily A Barber
- Hematology Section, Department of Laboratory Medicine, National Institutes of Health Clinical Center, Bethesda, Maryland
| | - Layla M Saleh
- Hematology Section, Department of Laboratory Medicine, National Institutes of Health Clinical Center, Bethesda, Maryland
| | - Adriana Zingone
- Multiple Myeloma Section, Metabolism Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland
| | - Azam Ghafoor
- Hematology Section, Department of Laboratory Medicine, National Institutes of Health Clinical Center, Bethesda, Maryland
| | - Rene Costello
- Multiple Myeloma Section, Metabolism Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland
| | - Yong Zhang
- Multiple Myeloma Section, Metabolism Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland
| | - Roger J Kurlander
- Hematology Section, Department of Laboratory Medicine, National Institutes of Health Clinical Center, Bethesda, Maryland
| | - Neha Korde
- Multiple Myeloma Section, Metabolism Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland
| | - Aldo M Roccaro
- Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts
| | - Irene M Ghobrial
- Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts
| | - Ola Landgren
- Multiple Myeloma Section, Metabolism Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland
| | - Katherine R Calvo
- Hematology Section, Department of Laboratory Medicine, National Institutes of Health Clinical Center, Bethesda, Maryland.
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Yanai A, Laver CRJ, Joe AW, Viringipurampeer IA, Wang X, Gregory-Evans CY, Gregory-Evans K. Differentiation of human embryonic stem cells using size-controlled embryoid bodies and negative cell selection in the production of photoreceptor precursor cells. Tissue Eng Part C Methods 2013; 19:755-64. [PMID: 23363370 DOI: 10.1089/ten.tec.2012.0524] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
We proposed to optimize the retinal differentiation protocols for human embryonic stem cells (hESCs) by improving cell handling. To improve efficiency, we first focused on the production of just one retinal precursor cell type (photoreceptor precursor cells [PPCs]) rather than the production of a range of retinal cells. Combining information from a number of previous studies, in particular the use of a feeder-free culture medium and taurine plus triiodothyronine supplements, we then assessed the values of using size-controlled embryoid bodies (EBs) and negative cell selection (to remove residual embryonic antigen-4-positive hESCs). Using size-controlled 1000 cell EBs, significant improvements were made, in that 78% CRX+ve PPCs could be produced in just 17 days. This could be increased to 93% PPCs through the added step of negative cell selection. Improved efficiency of PPC production will help in efforts to undertake shorter and larger preclinical studies as a prelude to future clinical trials.
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Affiliation(s)
- Anat Yanai
- Department of Ophthalmology and Visual Sciences, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
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