Inorganic Phosphorus and Potassium Are Putative Indicators of Delayed Separation of Whole Blood

Assessment of avian health status: suitability and constraints of the Zoetis VetScan VS2 blood analyser for ecological and evolutionary studies

Biochemical analyses of blood can decipher physiological conditions of living animals and unravel mechanistic underpinnings of life-history strategies and trade-offs. Yet, researchers in ecology and evolution often face constraints in which methods to apply, not least due to blood volume restrictions or field settings. Here, we test the suitability of a portable biochemical analyser (Zoetis VetScan VS2) for ecological and evolutionary studies that may help solve those problems. Using as little as 80 µl of whole-bird blood from free-living Jackdaws (Corvus monedula) and captive Zebra Finches (Taeniopygia guttata), we show that eight (out of 10) blood analytes show high repeatability after short-term storage (approximately 2 h) and six after 12 h storage time. Handling stress had a clear impact on all except two analytes by 16 min after catching. Finally, six analytes showed consistency within individuals over a period of 30 days, and three even showed individual consistency over a year. Taken together, we conclude that the VetScan VS2 captures biologically relevant variation in blood analytes using just 80 µl of whole blood and, thus, provides valuable physiological measurements of (small) birds sampled in semi-field and field conditions.

Concordance in COVID-19 serology, bone mineralization, and inflammatory analytes between venous and self-collected capillary blood samples exposed to various pre-analytical conditions

BACKGROUND

The COVID-19 has led to a significant increase in demand for remote blood sampling in clinical trials. This study aims to ascertain the concordance between venous versus capillary samples, processed immediately or exposed to various pre-analytical conditions.

METHODS

Participants (≥12 years old) provided a venous blood sample (processed immediately) and capillary samples allocated to one of the following conditions: processed immediately or exposed to 12-, 24-, or 36-h delays at room temperature or 36-h delays with a freeze-thaw cycle. The analytes of interest included SARS-CoV-2 IgG, 25-hydroxy vitamin D (25(OH)D), alkaline phosphate (ALP), calcium (Ca), phosphate (Ph), and c-reactive protein (CRP). Paired samples were considered interchangeable if they met three criteria: minimal within-subject mean difference, 95% of values within desirable total errors, and inter-class correlation (ICC) > 0.90.

RESULTS

90 participants (44.1% male) were enrolled. When comparing rapidly processed venous with capillary samples, 25(OH)D, ALP, and CRP met all three criteria; SARS-CoV-2 IgG met two criteria (mean difference and ICC); and Ca and Ph met one criterion (mean difference). When considering all three criteria, concentrations of 25(OH)D, CRP, and ALP remained unchanged after delays of up to 36 h; SARS-CoV-2 IgG met two criteria (mean difference and ICC); Ca and Ph met one criterion (mean difference).

CONCLUSION

These findings suggest that remote blood collection devices can be used to measure anti-SARS-CoV-2 IgG, 25(OH)D, CRP, and ALP. Further analysis is required to evaluate the interchangeability between venous and capillary testing in Ca and Ph levels, which are more sensitive to pre-analytical conditions.

Blood Plasma Quality Control by Plasma Glutathione Status

Timely centrifugation of blood for plasma preparation is a key step to ensure high plasma quality for analytics. Delays during preparation can significantly influence readouts of key clinical parameters. However, in a routine clinical environment, a strictly controlled timeline is often not feasible. The next best approach is to control for sample preparation delays by a marker that provides a readout of the time-dependent degradation of the sample. In this study, we explored the usefulness of glutathione status as potential marker of plasma preparation delay. As the concentration of glutathione in erythrocytes is at least two orders of magnitude higher than in plasma, even the slightest leakage of glutathione from the cells can be readily observed. Over the 3 h observation period employed in this study, we observed a linear increase of plasma concentrations of both reduced (GSH) and oxidized glutathione (GSSG). Artificial oxidation of GSH is prevented by rapid alkylation with N-ethylmaleimide directly in the blood sampling vessel as recently published. The observed relative leakage of GSH was significantly higher than that of GSSG. A direct comparison with plasma lactate dehydrogenase activity, a widely employed hemolysis marker, clearly demonstrated the superiority of our approach for quality control. Moreover, we show that the addition of the thiol alkylating reagent NEM directly to the blood tubes does not influence downstream analysis of other clinical parameters. In conclusion, we report that GSH gives an excellent readout of the duration of plasma preparation and the associated pre-analytical errors.

Proteomics and Lipidomics in Inflammatory Bowel Disease Research: From Mechanistic Insights to Biomarker Identification

Inflammatory bowel disease (IBD) represents a group of progressive disorders characterized by recurrent chronic inflammation of the gut. Ulcerative colitis and Crohn's disease are the major manifestations of IBD. While our understanding of IBD has progressed in recent years, its etiology is far from being fully understood, resulting in suboptimal treatment options. Complementing other biological endpoints, bioanalytical "omics" methods that quantify many biomolecules simultaneously have great potential in the dissection of the complex pathogenesis of IBD. In this review, we focus on the rapidly evolving proteomics and lipidomics technologies and their broad applicability to IBD studies; these range from investigations of immune-regulatory mechanisms and biomarker discovery to studies dissecting host⁻microbiome interactions and the role of intestinal epithelial cells. Future studies can leverage recent advances, including improved analytical methodologies, additional relevant sample types, and integrative multi-omics analyses. Proteomics and lipidomics could effectively accelerate the development of novel targeted treatments and the discovery of complementary biomarkers, enabling continuous monitoring of the treatment response of individual patients; this may allow further refinement of treatment and, ultimately, facilitate a personalized medicine approach to IBD.

Impact of Preanalytical Variations in Blood-Derived Biospecimens on Omics Studies: Toward Precision Biobanking?

Research data and outcomes do vary across populations and persons, but this is not always due to experimental or true biological variation. Preanalytical components of experiments, be they biospecimen acquisition, preparation, storage, or transportation to the laboratory, may all contribute to apparent variability in research data, outcomes, and interpretation. The present review article and biobanking innovation analysis offer new insights with a summary of such preanalytical variables, for example, the type of blood collection tube, centrifugation conditions, long-term sample storage temperature, and duration, on output of omics analyses of blood-derived biospecimens: whole blood, serum, plasma, buffy coat, and peripheral blood mononuclear cells. Furthermore, we draw parallels from the field of precision medicine in this study, with a view to the future of "precision biobanking" wherein such preanalytical variations are carefully taken into consideration so as to minimize their influence on outcomes of omics data, analyses, and sensemaking, particularly in clinical omics applications. We underscore the need for using broadly framed, critical, independent, social and political science, and humanities research so as to understand the multiple possible future trajectories of, and the motivations and values embedded in, precision biobanking that is increasingly relevant in the current age of Big Data.

Instability of Plasma and Serum Progastrin-Releasing Peptide During Repeated Freezing and Thawing

Objectives

Progastrin-releasing peptide (proGRP) is a promising biomarker for small cell lung cancer. However, not much is known about how sample processing and storage conditions affect the stability of proGRP. Here, we examined the effects of repeated freeze–thaw cycles on the stability of proGRP in plasma and serum.

Methods

Concentrations of proGRP were measured in plasma and serum samples exposed to two, three, or four freeze–thaw cycles and these were compared with values of corresponding samples exposed to one cycle (baseline). We also performed the area under the receiver-operating-characteristic curve (AUC) analysis to determine whether the differences of proGRP concentrations between each paired plasma and serum sample (ΔproGRP) can be used for identifying the samples that have been exposed to multiple freeze–thaw cycles.

Results

Concentrations of proGRP gradually decreased in both plasma and serum samples with increasing numbers of freeze–thaw cycles. Reduction rates of proGRP concentrations were greater in serum than in plasma samples and serum proGRP levels declined with statistical significance (p < 0.001) up to 10.1% after four freeze–thaw cycles. The ΔproGRP measurement showed fair accuracy (AUC = 0.741) for identifying samples that had been through four freeze–thaw cycles. The sensitivity was 82.8% and specificity was 62.1% at an optimal cut-off point of > 4.9.

Conclusion

Our study shows that the stability of circulating proGRP is affected in both plasma and serum samples by repeated freezing and thawing. We also show that ΔproGRP could be used for identifying paired plasma and serum samples subjected to multiple freeze–thaw cycles.