Refrigerated storage improves the stability of the complete blood cell count and automated differential

Common and Novel Markers for Measuring Inflammation and Oxidative Stress Ex Vivo in Research and Clinical Practice-Which to Use Regarding Disease Outcomes?

Many chronic conditions such as cancer, chronic obstructive pulmonary disease, type-2 diabetes, obesity, peripheral/coronary artery disease and auto-immune diseases are associated with low-grade inflammation. Closely related to inflammation is oxidative stress (OS), which can be either causal or secondary to inflammation. While a low level of OS is physiological, chronically increased OS is deleterious. Therefore, valid biomarkers of these signalling pathways may enable detection and following progression of OS/inflammation as well as to evaluate treatment efficacy. Such biomarkers should be stable and obtainable through non-invasive methods and their determination should be affordable and easy. The most frequently used inflammatory markers include acute-phase proteins, essentially CRP, serum amyloid A, fibrinogen and procalcitonin, and cytokines, predominantly TNFα, interleukins 1β, 6, 8, 10 and 12 and their receptors and IFNγ. Some cytokines appear to be disease-specific. Conversely, OS-being ubiquitous-and its biomarkers appear less disease or tissue-specific. These include lipid peroxidation products, e.g., F2-isoprostanes and malondialdehyde, DNA breakdown products (e.g., 8-OH-dG), protein adducts (e.g., carbonylated proteins), or antioxidant status. More novel markers include also -omics related ones, as well as non-invasive, questionnaire-based measures, such as the dietary inflammatory-index (DII), but their link to biological responses may be variable. Nevertheless, many of these markers have been clearly related to a number of diseases. However, their use in clinical practice is often limited, due to lacking analytical or clinical validation, or technical challenges. In this review, we strive to highlight frequently employed and useful markers of inflammation-related OS, including novel promising markers.

Assessment of transient changes in oxygen diffusion of single red blood cells using a microfluidic analytical platform

Red blood cells (RBCs) capability to deliver oxygen (O₂) has been routinely measured by P50. Although this defines the ability of RBCs to carry O₂ under equilibrium states, it cannot determine the efficacy of O₂ delivery in dynamic blood flow. Here, we developed a microfluidic analytical platform (MAP) that isolates single RBCs for assessing transient changes in their O₂ release rate. We found that in vivo (biological) and in vitro (blood storage) aging of RBC could lead to an increase in the O₂ release rate, despite a decrease in P50. Rejuvenation of stored RBCs (Day 42), though increased the P50, failed to restore the O₂ release rate to basal level (Day 0). The temporal dimension provided at the single-cell level by MAP could shed new insights into the dynamics of O₂ delivery in both physiological and pathological conditions.

Stability of hematological analytes during 48 hours storage at three temperatures using Cell-Dyn hematology analyzer

Background

The complete blood count (CBC) with differential leukocyte count (DLC) is one of the most common tests requested by physicians. The results of this test are affected by storage temperature and time of incubation. This study was designed to evaluate the stability of hematologic parameters in blood specimens stored for 48 h at three temperatures.

Methods

K2-EDTA - blood was collected from 22 healthy adults. The CBC was performed using a hematology analyser immediately; 0 time point and at 4, 8, 12, 16, 20, 24, and 48 h after storage at 4 °C, 10 °C or 23 °C. Changes in values of CBC parameters from the 0 time point were determined and reported as % of the initial value.

Results

Red blood cells, platelet, hemoglobin, and mean corpuscular hemoglobin were found stable during 48 h storage at 4 °C, 10 °C or 23 °C. Hematocrite and mean corpuscular volume increased, while white blood cells decreased at 48 h when stored at 23 °C. Lymphocytes, neutrophils, eosinophils, and basophils showed significant differences after 12 h of storage at 23 °C.

Conclusions

Red blood cells, platelet, hemoglobin, and mean corpuscular hemoglobin are the only suitable parameters without refrigeration during 24 h storage. When CBC and DLC are performed, 4 °C can be recommended as the most suitable storage temperature for 12 h storage.

Red Blood Cells and Platelets Conventional and Research Parameters: Stability Remarks Before Their Interpretation

OBJECTIVES

To analyze the stability of red blood cells, platelets, and reticulocytes of the research parameters, in combination with the respective conventional parameters, for each analyte; and to quantify the morphological changes in these analytes, to propose a correction factor for each.

METHODS

Ethylenediaminetetraacetic acid (EDTA) blood specimens from patients were reanalyzed in 2-hour intervals and then, the mean percentage (X¯t%) changes were calculated. To evaluate the stability of the analyzed material, we used different criteria according to within-run and between-batch analytical variation, as well as intraindividual biological variation. Next, the mean deviation percentage of the parameters that undergo time-dependent significant changes was calculated, to obtain a correction factor.

RESULTS

Several conventional and research parameters showed significant alterations in the stability at an early time after arrival at the laboratory.

CONCLUSION

Cell variations over time can be quantified and corrected by applying a multiplying factor to the signal obtained in the analyzer.

Short-Term Stability of Hematologic Parameters in Frozen Whole Blood

BACKGROUND

Complete blood counts (CBCs) are commonly obtained in large multicenter studies. We assessed the stability of 10 parameters after short-term (up to 30 days) frozen storage.

METHODS

We compared CBC measurements from fresh samples (n = 53) with samples stored for up to 30 days at -70 °C. We calculated the CVs and intraclass correlation coefficients.

RESULTS

Mean values of most parameters, with the exception of hemoglobin and platelet count, were significantly different by 15 days of storage. White blood cell count (CV, 38.3%; 95% CI, 31.3%-46.2%) and red cell distribution width (CV, 37.7%; 95% CI, 34.1%-41.3%) were the most variable. After 30 days, only hemoglobin remained stable and reliable (CV, 0.8%; 95% CI, 0.4%-1.3%).

CONCLUSIONS

Hemoglobin remained stable in frozen blood samples stored for up to 30 days at -70 °C and may be reliably used in research studies using short-term frozen specimens. Other CBC parameters measured in stored blood are not sufficiently reliable for research or patient care.

The chemical and laboratory investigation of hemolysis

The abnormal breakdown of circulating red blood cells (RBCs), also known as hemolysis, is a significant clinical issue that can present as a primary disorder or arise secondary to another disease process. The evaluation for pathologic hemolysis (and the establishment of a hemolytic disorder) is heavily dependent on assays performed and overseen by the divisions of Hematology, Blood Bank/Transfusion Medicine, Clinical Chemistry, and Immunology in the clinical laboratory. Because of the wide variety of assays used across the spectrum of clinical pathology and potential pitfalls/limitations associated with this testing, the decision of which assay to choose and, perhaps more importantly, how to interpret results, can both be quite challenging. Thus, the aim of this manuscript is to provide a comprehensive review on the laboratory investigation of pathologic forms of hemolysis and hemolytic disorders. This chapter will: (1) introduce basic concepts on the pathophysiology of hemolysis and (2) examine assays available for hemolysis on a laboratory-by-laboratory basis, with a particular emphasis on the strengths, limitations, and clinical interpretations of each of these assays.

Changes of hematological references depends on storage period and temperature conditions in rats and dogs

Because changes in rat and dog hematological parameters according to storage conditions have been poorly documented, we sought to examine such changes. Blood analysis was performed using two hematology analyzers (ADVIA 2120i and Sysmex XN-V) after storage at room temperature and in cold storage for 5, 24, and 48 h, respectively. Interassay coefficients of variation for hematological parameters analyzed with the ADVIA 2120i and the XN-V showed similar. The levels of hematocrit, mean corpuscular volume, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, and platelet (PLT) showed significant variations with time in blood samples of rats and dogs. The leukocyte subpopulation showed high variation with storage conditions. The data for leukocyte differential counts obtained using the ADVIA 2120i, XN-V, and a manual differential counting procedure showed good agreement for neutrophils and lymphocyte counts, but monocytes, eosinophils, and basophils showed differences between the procedures. In conclusions, most rat and dog hematological parameters showed minimal changes; however, some showed high variation with storage time and temperature, especially PLT and leukocyte subpopulations. In conclusion, when performing hematological analysis in dogs and rats, it will be exactitude to analyze blood samples in fresh condition and at least within 24 h in the cold storage.

Blood haemogram in Ovis aries and Capra hyrcus: effect of storage time

The aim of the present study was to assess the effect of storage time at +4 °C on haematological profile in goat (n = 25) and sheep (n = 25). After collection, blood samples were immediately analyzed and then divided into four aliquots that were stored at 4 °C and tested at 24 h (T1), 48 h (T2), 72 h (T3), and 1 wk (T4), respectively. One-way repeated-measures analysis of variance (ANOVA) was used to determine statistically significant effect of storage conditions both in goats and in sheep. Our results showed that among the two species studied, goats showed highest blood stability after refrigeration at +4 °C. In goats, all hematological parameters, except PLT, showed no significant changes during all days of monitoring with respect to basal values (T0). In sheep, no significantly effect of storage time on RBC and WBC levels were found, whereas the other hematological parameters change significantly over the time. Our findings suggest that the blood storage time reported for goat may not be applied to sheep’s blood, which underscore the differences between these two species that are erroneously considered similar.

Two-stage, in silico deconvolution of the lymphocyte compartment of the peripheral whole blood transcriptome in the context of acute kidney allograft rejection

Acute rejection is a major complication of solid organ transplantation that prevents the long-term assimilation of the allograft. Various populations of lymphocytes are principal mediators of this process, infiltrating graft tissues and driving cell-mediated cytotoxicity. Understanding the lymphocyte-specific biology associated with rejection is therefore critical. Measuring genome-wide changes in transcript abundance in peripheral whole blood cells can deliver a comprehensive view of the status of the immune system. The heterogeneous nature of the tissue significantly affects the sensitivity and interpretability of traditional analyses, however. Experimental separation of cell types is an obvious solution, but is often impractical and, more worrying, may affect expression, leading to spurious results. Statistical deconvolution of the cell type-specific signal is an attractive alternative, but existing approaches still present some challenges, particularly in a clinical research setting. Obtaining time-matched sample composition to biologically interesting, phenotypically homogeneous cell sub-populations is costly and adds significant complexity to study design. We used a two-stage, in silico deconvolution approach that first predicts sample composition to biologically meaningful and homogeneous leukocyte sub-populations, and then performs cell type-specific differential expression analysis in these same sub-populations, from peripheral whole blood expression data. We applied this approach to a peripheral whole blood expression study of kidney allograft rejection. The patterns of differential composition uncovered are consistent with previous studies carried out using flow cytometry and provide a relevant biological context when interpreting cell type-specific differential expression results. We identified cell type-specific differential expression in a variety of leukocyte sub-populations at the time of rejection. The tissue-specificity of these differentially expressed probe-set lists is consistent with the originating tissue and their functional enrichment consistent with allograft rejection. Finally, we demonstrate that the strategy described here can be used to derive useful hypotheses by validating a cell type-specific ratio in an independent cohort using the nanoString nCounter assay.

Changes in hematology measurements in healthy and diseased dog blood stored at room temperature for 24 and 48 hours using the XT-2000iV analyzer

BACKGROUND

Changes in canine hematology measurements may occur when analyses are delayed due to shipment of specimens to a laboratory.

OBJECTIVE

The purpose of this study was to report changes in hematologic variables in healthy and diseased canine blood measured with a Sysmex XT-2000iV during storage at room temperature for 24 and 48 hours.

METHODS

EDTA-K3 blood samples from 42 healthy and diseased dogs were measured on a Sysmex XT-2000iV analyzer within one hour of sampling, and after storage for 24 and 48 hours at room temperature in the dark.

RESULTS

Storage caused little or no change in RBC count, HGB concentration and MCH, while there was a moderate increase in HCT, MCV and reticulocytes count, and a moderate decrease in MCHC. Decreased platelet counts by impedance (PLT-I) and optical (PLT-O) measurements were associated with increased mean platelet volume (MPV), platelet-large cell ratio (P-LCR) and platelet distribution width (PDW), including a right shift in the platelet histogram and a dispersion of the platelet dot plot on the scattergram. The total and differential WBC count remained stable except for decreased monocyte counts. In the scatterplots, monocytes shifted into the lymphocyte population after 24 hours, and neutrophil population shifted to the right appearing in the eosinophil gate at 48 hours of storage. The disease status had only a small effect on storage-induced changes, and observed changes had no consequences for clinical decisions.

CONCLUSIONS

Blood storage at room temperature was accompanied by moderate variations in some hematologic variables, awareness of which helps in avoiding misinterpretations.

Effect of storage on microcytosis observed in dogs with portosystemic vascular anomalies

Microcytosis is a common laboratory finding in dogs with iron deficiency and congenital portosystemic vascular anomalies (PSVA), however artefactual changes due to blood storage may occur which could mask this feature. This study evaluated the effects of storage on microcytosis in dogs with congenital PSVA. Full haematological parameters were measured on the day of sampling and following 24h storage at room temperature, in unaffected dogs (n=13) and in dogs affected with PSVA (n=24). Storage for 24h resulted in significantly higher MCV values in both groups of dogs (P<0.01). The percentage increase in MCV was greater in the control dogs (median 8.07%, range 5.64-9.31%) compared to affected dogs (median 6.05%, range 3.12-15.21%) (P<0.02). Storage of 1ml EDTA blood samples at ambient temperature for 24h prior to analysis, as occurs when samples are posted to external laboratories, will have significant effects on MCV and may mask microcytosis in dogs with PSVA.

Effects of temperature and duration of sample storage on the haematological characteristics of western grey kangaroos (Macropus fuliginosus)

OBJECTIVE

To investigate the effects of storage duration and temperature on haematological analyses performed on blood from the western grey kangaroo (Macropus fuliginosis).

METHOD

Blood samples from five western grey kangaroos were stored at 4 degrees C, 24 degrees C and 36 degrees C. Each sample was analysed haematologically over a 5-day period.

RESULTS

The blood samples maintained optimal stability at 4 degrees C. At this temperature the haematological values remained essentially unchanged for the duration of the study, while samples stored at 36 degrees C and 24 degrees C showed significant changes in some haematological measures by 12 h and 48 h, respectively. Disturbances in leukocyte morphology were evident, to varying degrees, in all samples.

CONCLUSIONS

Blood samples from macropodids should be tested within 48 h of collection if stored at a room temperature of about 24 degrees C. Where testing is to be delayed for more than 48 h, samples should be refrigerated as soon as possible. Exposure of samples to heat in excess of 24 degrees C should be avoided at all times.

Stability of blood cell counts, hematologic parameters and reticulocytes indexes on the Advia A120 hematologic analyzer

Delayed sample analysis is not a rare circumstance in clinical and laboratory practice, especially when blood samples are shipped to distant centralized laboratories, when the analysis can not be readily performed, or when retesting is appropriate. In this study we sought to evaluate the stability of conventional and new hematologic parameters in blood specimens stored for as long as 24 hours at 4 degrees C. Of the 21 hematologic parameters tested with the use of the Advia 120 hematologic analyzer (Bayer Diagnostics), means for paired samples of specimens differed significantly over the 24-hour storage period for hematocrit, main corpuscular volume, percentage of macrocytes, platelet count, main platelet volume, reticulocyte count and percentage, and reticulocyte hemoglobin content (all P < .01). We noted no significant changes in the other parameters tested or in the white blood cell differential. The overall distribution of the immature reticulocytes fractions remained substantially unchanged, though the high staining-intensity fraction showed a considerable shift from the baseline measure. Bland-Altman plots and limits-of-agreement analysis showed mean biases between -4.8% and 37.2% and relative coefficients of variations ranging from 0.4% to 32.7%. The 95% agreement interval in the set of differences was satisfactory and almost within the current analytic-quality specifications for desirable bias. The results of this investigation suggest that, within certain limitations for parameters derived or calculated from cellular volumes, blood specimens stored for as long as 24 hours at 4 degrees C may be suitable for hematologic testing.

Quality specification in haematology: the automated blood cell count

BACKGROUND

Quality specifications for automated blood cell counts include topics that go beyond the traditional analytic stage (imprecision, inaccuracy, quality control) and extend to pre- and post-analytic phases.

METHODS

In this review pre-analytic aspects concerning the choice of anticoagulants, maximum conservation times and differences between storage at room temperature or at 4 degrees C are considered. For the analytic phase, goals for imprecision and bias obtained with various approaches (ratio to biologic variation, state of the art, specific clinical situations) are evaluated. For the post-analytic phase, medical review criteria (algorithm, decision limit and delta check) and the structure of the report (general part and comments), which constitutes the formal act through which a laboratory communicates with clinicians, are considered.

RESULTS

K2EDTA is considered the anticoagulant of choice for automated cell counts. Regarding storage, specimens should be analyzed as soon as possible. Storage at 4 degrees C may stabilize specimens from 24 to 72 h when complete blood count (CBC) and differential leucocyte count (DLC) is performed. For precision, analytical goals based on the state of the art are acceptable while for bias this is satisfactory only for some parameters.

CONCLUSIONS

In haematology quality specifications for pre- and analytical phases are important, but the review criteria and the quality of the report play a central role in assuring a definite clinical value.

Artifactual changes in equine blood following storage, detected using the Advia 120 hematology analyzer

BACKGROUND

Delayed analysis of blood samples may be caused by restricted access to laboratories. Artifactual changes may occur in the measured analytes as a consequence of delayed analysis and may complicate interpretation of the data.

OBJECTIVE

The purpose of this study was to characterize artifactual changes in equine blood, due to storage, using the Advia 120 hematology analyzer.

METHODS

Samples of blood from 5 horses were analyzed using the Advia 120 soon after collection and again after 24 and 48 hours of storage at either 4 degrees C or ambient laboratory temperature ( approximately 24 degrees C).

RESULTS

Delayed analysis of equine blood samples resulted in increased numbers of normocytic hypochromic RBCs, increased numbers of macrocytic hypochromic RBCs, misclassification of granulocytes as mononuclear cells using the basophil reagent method, and pseudothrombocytosis, due to misclassification of ghost RBCs as platelets. The latter artifact was corrected by an amended version of the software. Many of the artifactual changes were identified by morphology flags.

CONCLUSIONS

Characteristic changes in cytograms produced by the Advia 120 allowed recognition of artifactual changes in stored equine blood samples. These changes were less pronounced in samples stored at 24 degrees C than at 4 degrees C.