Validation of a Blood Stability Score as an easy-to-use blood sample quality index

Measurement of Immature Reticulocytes in Dried Blood Spots by Mass Spectrometry

BACKGROUND

Immature reticulocytes (IRC) are the first cells to respond to changes in erythropoiesis. For antidoping applications, measurement of IRC may improve detection of blood doping practices. Unfortunately, this small cell population has limited stability in liquid blood samples and is difficult to measure with optimal precision. We developed a method to measure 3 IRC membrane proteins in dried blood spots (DBS) to monitor changes in erythropoiesis.

METHODS

DBS spots were washed with buffers to remove soluble proteins, membrane proteins remaining in the spot were digested with trypsin, and one peptide for each protein was measured by LC-MS/MS. IRC protein concentration was determined using a DBS single point calibrator.

RESULTS

Intraassay precision for IRC proteins was between 5%-15%. IRC proteins were stable in DBS for 29 days at room temperature. In a longitudinal study of 25 volunteers, the mean intraindividual variation for 3 IRC proteins was 17%, 20%, and 24% from capillary blood DBS. In comparison, the mean longitudinal variation for IRC counts measured on an automated hematology analyzer was 38%. IRC protein concentration from capillary blood DBS correlated well with venous blood DBS protein concentrations.

CONCLUSIONS

Measurement of IRC proteins in DBS samples provides a method to measure changes in erythropoiesis with improved analytical sensitivity, stability, and precision. When combined with the inherent advantages of capillary blood collection in the field, this method may substantially improve the detection of blood doping practices.

Stability of complete blood count parameters depends on the storage temperature, storage time, transport position and selected stability criterion

Purpose: To evaluate stability of CBC parameters in samples containing K₃-EDTA in Hema&Tube brand evacuated tubes stored at 4 °C and room temperature in upright, horizontal and upside-down transport positions for up to 240 min by comparing with different stability criteria. Methods: A total of 450 outpatient samples, 75 for each condition, were stored for 240 min. Blood samples were analyzed at baseline, 60th, 120th and 240th min of storage time using Sysmex® XT-4000i hematology analyzer. CBC results were compared according to the paired samples t-test, one CV% change, CVI, BV DES 2014, RCPA, IQMH, EFLM Biological Variation 2019, ESfEQAand CLIA stability criteria. Results: In all transport conditions, almost all CBC parameters were unstable according to the paired samples t-test. Based on one CV % change RBC, hemoglobin, hematocrit, RDW-CV, neutrophils, platelets, MPV, PDW and plateletcrit were unstable in some transport conditions. However, most parameters were stable at all conditions, except especially for MCH, MPV, PDW and plateletcrit, while just MPV and PDW were unstable at RT in all transport conditions according to the lower and higher CVI, respectively. Conclusions: Paired samples t-test and one CV% change stability criteria are not suitable for decision. Clinical laboratories should establish the impact of storage time, storage temperature and transport positions for each CBC parameter while paying attention to the brand of evacuated tube according to the lower CVI of biological variation data stability criteria since it is more related to the impact of analysis deviation on clinical decisions to prevent misdiagnosis.

Fighting Doping in Elite Sports: Blood for All Tests!

In the fight against doping, detection of doping substances in biological matrices is paramount. Analytical possibilities have evolved and sanctioning a doping scenario by detecting forbidden bioactive compounds circulating unmodified in blood is nowadays very attractive. In addition, the World Anti-Doping Agency (WADA) introduced the Athlete Biological Passport (ABP) a decade ago as a new paradigm inferring the use of prohibited substances or methods through longitudinal profiling, or serial analyses of indirect biomarkers of doping, to be both scientifically and legally robust. After the introduction in 2008 of an hematological module (i.e., based on variations of blood variables) aiming to identify enhancement of oxygen transport and any form of blood transfusion or manipulation, a urinary steroidal module was additionally introduced in 2014 composed of concentrations and ratios of various endogenously produced steroidal hormones. Some evidence tends to discredit steroid profiles obtained from urine analyses to detect the use of endogenous androgenic anabolic steroids (EAAS), when administered exogenously, due to high rates of false negatives with short half-life and topical formulations rendering profile alteration only minimal or equivocal. On the other hand, steroid hormones quantification in blood showed a promising ability to detect testosterone doping and interesting complementarities to the ABP thanks to the most recent analytical techniques (UHPLC-HRMS or/and MS/MS). This perspective article explores the opportunities of blood samples to monitor not only hematological but also steroid profiles in elite athletes.

Development of two complementary LC–HRMS methods for analyzing sotatercept in dried blood spots for doping controls

Aim: sotatercept is a therapeutic Fc-fusion protein with erythropoiesis-stimulating activity. Due to a potential abuse of the drug by athletes in professional sports, a sensitive detection method is required. In sports drug testing, alternative matrices such as dried blood spots (DBS) are gaining increasing attention as they can provide several advantages over conventional matrices. Materials & methods: Herein, two complementary LC–high-resolution mass spectrometry (HRMS) detection methods for sotatercept from DBS, an initial testing procedure (ITP) and a confirmation procedure (CP) were developed and validated for the first time. Both methods comprise an ultrasonication-assisted extraction, affinity enrichment, proteolytic digestion and HRMS detection. Results & conclusion: For the multianalyte ITP, artificial samples fortified with sotatercept, luspatercept and bimagrumab, and authentic specimens containing bimagrumab were successfully analyzed as proof-of-concept. The validated detection methods for sotatercept are fit for purpose and the ITP was shown to be suitable for the detection of novel IgG-based pharmaceuticals in doping control DBS samples.

Stability of leukocyte research parameters over time on the Sysmex XN: How to quantify the changes in cell morphology

INTRODUCTION

Research parameters of the Sysmex XN-series provide information about the cell morphology. The aim is to quantify time-dependent changes of conventional and research parameters and propose correction factors to be applied to the parameters, which revealed significant changes.

METHODS

284 EDTA blood samples were processed from 0 hours-12 hours and the mean percentage change ( X ¯ t %) of the leukocyte parameters was calculated. Stability was evaluated according to three criteria: metrology criteria according to the between-batch analytical variation, metrology criteria according to within-run analytical variation, by which X ¯ t % could not exceed the Minimum Significant Change (MSC = [±1.65*CV%]) and Biological criteria based on intraindividual biological variation, by which X ¯ t % could not exceed the Desirable Significant Change (DSC = [±0.5*CV_D %]). Mean deviation percentage of the parameters, which suffer significant changes was calculated and a multiplying factor was obtained to correct the signal deviation. Stability of abnormal leukocyte flags was also evaluated.

RESULTS

Most of the cell count parameters are considered stable according to MSC and DSC. However, several research parameters of neutrophils and lymphocytes show alterations in stability after 4 hours, even when their respective cell count parameters are stable.

CONCLUSION

Morphological variations of neutrophils and lymphocytes can be quantified. This data can be used to correct the deviation in samples that cannot be analyzed before 4 hours.