Quality assurance of progenitor cell content of apheresis products: a comparison of clonogenic assays and CD34+ enumeration

Chin‐Yee,; Cantin,; Giulivi,; Gluck,; Keating,; Keeny,; Klassen,; Sutherland,

doi:10.1046/j.1365-3148.2000.00233.x

Cited by 19 publications

(16 citation statements)

References 16 publications

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“…Therefore, various national and international guidelines for CD34þ cell enumeration have been formulated (24,(26)(27)(28). Nevertheless, in various multicentre studies (29)(30)(31)(32)(33)(34)(35)(36)(37)(38)(39)(40) large variations between results of individual centers were observed. The outcome of CD34þ cell enumeration assays depends on several variables, such as sample source, sample processing, technical experience, and data analysis techniques.…”

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confidence: 99%

Flow cytometric CD34+ stem cell enumeration: Lessons from nine years' external quality assessment within the Benelux countries

Levering

Preijers

Wieringen

et al. 2007

Cytometry Part B Clinical

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Background: A biannual external quality assurance (EQA) scheme for flow cytometric CD34+ haematopoietic stem cell enumeration has been operational in the Benelux countries since 1996. In an evaluation of the results of 16 send-outs, we studied the effects of the methods used on assay outcome and whether or not this exercise was effective in reducing between-laboratory variation.Methods: Data were analyzed using robust multivariate regression. This approach is relatively insensitive to outliers and is used to assess the effect of methodological aspects of CD34+ cell counting on the bias and variability.Results: Five variables were associated with significant bias of absolute CD34+ cell counts: (i) unique laboratory number (ULN), (ii) gating strategy; (iii) CD34 mAb fluorochrome; (iv) type of flow cytometer, and (v) method of sample preparation. In addition, ULN and platform methodology (i.e., single vs. dual) contributed significantly to the variability of this assay. Overall, the variability in results of CD34+ cell enumeration has declined with time; in particular, after a practical workshop in which participants were trained to use the ''single platform ISHAGE protocol.'' Conclusions: Between-laboratory variation in CD34+ cell enumeration can be reduced by standardization of methodologies between centres. Our approach, i.e., EQA with targeted training and feedback in response to reported results, has been successful in reducing the variability of CD34+ cell enumeration between participants. q 2007 Clinical Cytometry Society

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confidence: 99%

Flow cytometric CD34+ stem cell enumeration: Lessons from nine years' external quality assessment within the Benelux countries

Levering

Preijers

Wieringen

et al. 2007

Cytometry Part B Clinical

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“…2 The variability occurs even when standardized media and growth factor combinations are used. 11 In addition, the 2-week incubation period for a clonogenic assay renders this method impractical for post cryopreservation assessment as there is typically a short time period between the request for release of cryopreserved HPC and the reinfusion into a patient.…”

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confidence: 99%

Effects of incubation temperature and time after thawing on viability assessment of peripheral hematopoietic progenitor cells cryopreserved for transplantation

Yang

Acker

Cabuhat

et al. 2003

Bone Marrow Transplant

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Summary:Three widely used viability assessments were compared: (1) membrane integrity of nucleated cells using trypan blue (TB) exclusion and a fluorometric membrane integrity assay (SYTO 13 and propidium iodide), (2) enumeration of viable CD34 þ cells, and (3) clonogenic assay (granulocyte-macrophage colony-forming units, CFU-GM). Post thaw peripheral hematopoietic progenitor cells (HPC) were incubated at 0, 22, and 371C for 20-min intervals before assessment. The recovery of viable nucleated cells assessed by TB and SYTO/PI decreased significantly with time at incubation temperatures of 22 and 371C (Po0.05), and correlated with the concentration of mononuclear cells (MNC) (r ¼ 0.936, Po0.05). The decrease in recovery of viable nucleated cells was slower when thawed cells were incubated at 01C compared with 221C or 371C. The recovery, measured by absolute viable CD34 þ or CFU-GM, was not affected by 2 h post thaw incubation (P40.05) at 0, 22, and 371C (P40.05). There were no significant differences in the measured recovery of viable CD34 þ cells and CFU-GM at all incubation times (P40.05) and temperatures (P40.05). Both CFU-GM and absolute CD34 þ cells can be used as post thaw viability assays for HPC cryopreserved for transplantation.

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“…CD34 analysis was performed using a Becton-Dickinson FACS-Calibur flow cytometer (Becton-Dickinson, San Jose, CA, USA) and the method that has been advanced by Sutherland and colleagues 7,8 ('ISHAGE double platform method'). Our laboratory bench marks our use of this method by continually meeting passing criteria for the College of American Pathologists (Northfield, IL, USA) semi-annual proficiency test for CD34 enumeration.…”

Section: Cell Counts and Cd34 Assessmentmentioning

confidence: 99%

Apheresis and transplant of hematopoietic progenitor cells (HPC) from allogeneic donors of age above 60 years

Janssen

Rahn

Hackett

et al. 2012

Bone Marrow Transplant

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Over the immediate past 4 years, our program has collected hematopoietic progenitor cells by apheresis from 48 individuals aged 61 and over (range 61-71 years of age). We have retrospectively analyzed the collection and transplant results associated with employing these donors, and have compared them with 175 donors aged 60 or less who were collected during the same time period. We have found no significant difference in venous access (P ¼ 0.208), rate of post-transplant engraftment of neutrophils (P ¼ 0.117) and platelets (P ¼ 0.692), or in rate and grade of acute GVHD (P ¼ 0.806). However, we have found that these older donors have a significantly lower mobilization of CD34 þ cells as reflected in lower absolute counts of circulating CD34 þ cells preapheresis (P ¼ 0.016). This, in turn, results in lower CD34 þ cell yields in apheresis products (Po0.001), trending towards requiring more apheresis procedures (22.9 vs 13.7%, P ¼ 0.095) to collect sufficient CD34 þ cells for transplantation. We conclude that it is practical when necessary to employ donors aged 60 and above, as well as safe for both donor and intended recipient. However, concern over reduced CD34 þ cell mobilization may be sufficient grounds to seek younger donors when possible.

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Quality assurance of progenitor cell content of apheresis products: a comparison of clonogenic assays and CD34+ enumeration

Cited by 19 publications

References 16 publications

Flow cytometric CD34+ stem cell enumeration: Lessons from nine years' external quality assessment within the Benelux countries

Flow cytometric CD34+ stem cell enumeration: Lessons from nine years' external quality assessment within the Benelux countries

Effects of incubation temperature and time after thawing on viability assessment of peripheral hematopoietic progenitor cells cryopreserved for transplantation

Apheresis and transplant of hematopoietic progenitor cells (HPC) from allogeneic donors of age above 60 years

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