Small Blood Samples Research Articles

On the Use of Image Analysis for Hematocrit Evaluation in Dried Blood Spots

Dried blood spots (DBSs) are formed by collecting a small sample of blood on specialized filter paper and allowing it to dry naturally. Various domains of life sciences and drug research extensively use DBSs as a sampling technique. The “Hematocrit (Ht) effect” affects assay bias, and several strategies have been put forth to deal with it, including the correction of quantified concentrations using an appropriate correction factor. The approach was previously applied, following the utilization of an image processing algorithm developed in Matlab® to derive a reliable equation correlating DBS areas to Ht% values. The present work looks more closely at the application of image analysis to the evaluation of Ht in DBS samples. Utilizing image analysis software, DBS samples with known Ht values were processed. Preparation of cards has followed a previously developed protocol for the appropriate formation of uniform area DBSs, irrespective of Ht. The resulting areas showed close resemblance to the respective theoretical areas calculated by applying the correlation equation. Following that, the equation was utilized to determine the Ht values for each sample, and a comprehensive comparison of measured versus calculated Ht was carried out using various statistical approaches for method comparison. The results demonstrated a strong correlation, suggesting the method’s viability in estimating Ht for unknown DBS samples.

7701 Comparative Analysis of Dried Blood Spot and Serum ELISAs for AMH, FSH, and LH in Patients Seeking IVF Treatment

Abstract Disclosure: T. Kumar: None. R. Chauhan: None. B. Kalra: None. A.S. Patel: None. S. Chauhan: None. A. Kumar: None. Relevance: Dried Blood Spot (DBS) technology has not been widely implemented in the diagnostic industry due to its limitations in obtaining reliable, quantitative data from small blood samples. However, recent advancements in methods, i.e., sensitive antibodies, homogeneous and reproducible paper quality, and painless needles have renewed the interest in the DBS collection technique. Objective: The aim of the study is to validate the hormone measurements using DBS technology and compare the correlation matrix between AMH, LH, FSH, inhibin B, Antral Follicle Counts (AFC), age, and BMI in patients seeking infertility workup. Materials and Methods: Matched serum and DBS samples from thirty-nine patients between the ages of 18 and 45 years were collected on day 3 of the cycle. The subjects were visiting the clinic for initial fertility workup and subjects on medications for ovarian suppression were excluded. The samples were tested on Ansh Labs DBS AMH (AL-129), FSH (AL-187), and LH (AL-190), PCOCheck AMH (N-N terminus, AL-196), picoAMH (C-N terminus, AL-124-r), US Inhibin B (AL-195) ELISAs. Baseline AFC obtained via transvaginal ultrasound, BMI, and age were collected. Spearman’s correlations, and regression analysis using Passing and Bablok were calculated to examine the relationship between AFC, AMH, inhibin B, FSH LH, age, and BMI. Results: DBS samples were highly correlated to their matched serum specimens. The slope and Spearman’s rank correlation (rs) between matched serum and DBS specimens for AMH, FSH, and LH were 1.17x, 1.07x, 1.07x, and 0.98, 0.93, and 0.97, respectively. DBS AMH strongly correlated with AFC. The Spearman’s rank correlation (rs) between AFC and DBS AMH, DBS LH, and DBS FSH were 0.80, -0.11, and -0.31, respectively. A strong correlation was observed between age and AMH, LH and FSH. A weak correlation was observed between BMI and AMH, LH and FSH. The Spearman’s rank correlation (rs) between age and DBS AMH, LH, and FSH were -0.34, 0.28, and 0.25, respectively. DBS AMH, LH, and FSH correlation with BMI were -0.06, 0.05, and 0.09, respectively. Inhibin B had a strong correlation to age (rs -0.33), BMI (rs -0.67), AFC (rs 0.44), DBS AMH (rs 0.40), DBS FSH (rs -0.19), DBS LH (rs-0.11), respectively. AMH method comparison between N-N and N-C terminal ELISA using 39 serum samples yielded slopes of 0.85x and Spearman’s rank correlation of 0.97. Conclusions: DBS and serum measurements for AMH, LH, and FSH are very accurate and precise. They can be used interchangeably. The strong relationship between BMI and Inhibin B will require further investigation and may open new avenues in obesity and reproductive endocrinology. Presentation: 6/1/2024

A-348 Portable aptamer-based home monitoring system for blood phenylalanine measurement

Abstract Background Aptatek BioSciences, Inc. has developed a home monitoring tool for blood phenylalanine (phe) levels. The Aptatek system integrates a proprietary aptamer assay approach with a user-friendly handheld, smartphone-enabled test platform. PKU (phenylketonuria), is an inborn error of phenylalanine (Phe) metabolism If undiagnosed or untreated, phe accumulates in all body tissues, including the blood and brain, where it is especially neurotoxic and when untreated it can cause significant cognitive impairment and neurological defects. PKU management targets maintaining blood Phe concentration within the therapeutic range (120-360uM) to avoid severe neurological sequelae, mainly through nutritional therapy. Methods PheCheck™ includes a portable hand-held reader, software accessible as a mobile phone application, and a disposable single-use lateral flow cassette, blood collection, cap, and buffer chamber. PheCheck™ detects phe by binding of the phe in a small blood sample using small molecule-specific DNA aptamers. A patient (or caregiver) collects 5μl of capillary blood using a lancet to lance the fingertip and use the collection cap to collect the specimen. Once collected, the specimen is placed into the buffer chamber where the blood is diluted and processed in preparation for a lateral flow assay. The buffer chamber is placed on top of a lateral flow cassette to release the solution into the cassette. The lateral flow cassette is inserted into a small electronic reader after specimen incubation. The reader will detect a fluorescent signal from the strip and report the quantitative Phe concentration present in the specimen to the integrated mobile phone application. The reader has a simple design with a single operating push button, USB data connection port, and replaceable battery compartment. The reader reads the output of the lateral flow cassette and reports the result to a Smartphone app. The app is designed to either display the quantitative results or store the results without displaying the quantitative value. Results Twelve patients were trained on the PheCheck system and observed using the system for self-testing. Patients also prepared dried blood spot cards for comparative testing using LC-mass spectrometry. Patients were asked to return to the clinic within two weeks to retest. The blood phenylalanine levels measured by the PheCheck system were within targeted standard deviation of the dried blood spots demonstrating the feasibility of portable home-based testing for routine monitoring of blood phenylalanine levels in phenylketonuria patients. Such a portable system would enable real time monitoring and adjustment of diet or therapy for chronic diseases such as PKU. Conclusions Aptatek has developed a DNA aptamer based portable monitor for measuring blood phenylalanine levels. The system quantitatively measures phenylalanine from a 5-microliter finger stick blood sampler. Aptamer-based detection of phenylalanine provides reliable quantitation across a wide clinical concentration range and encouraging performance relative to gold standard testing of venous blood draw or dried blood spots. Analysis of samples from patients on Palynziq indicate that the PheCheck system could provide more reliable testing than venous blood draws. The system shows strong promise for routine home monitoring of blood phe levels by patients.

Targeting chronic lymphocytic leukemia with B-cell activating factor receptor CAR T cells.

The challenge of disease relapsed/refractory (R/R) remains a therapeutic hurdle in chimeric antigen receptor (CAR) T-cell therapy, especially for hematological diseases, with chronic lymphocytic leukemia (CLL) being particularly resistant to CD19 CAR T cells. Currently, there is no approved CAR T-cell therapy for CLL patients. In this study, we aimed to address this unmet medical need by choosing the B-cell activating factor receptor (BAFF-R) as a promising target for CAR design against CLL. BAFF-R is essential for B-cell survival and is consistently expressed on CLL tumors. Our research discovered that BAFF-R CAR T-cell therapy exerted the cytotoxic effects on both CLL cell lines and primary B cells derived from CLL patients. In addition, the CAR T cells exhibited cytotoxicity against CD19-knockout CLL cells that are resistant to CD19 CAR T therapy. Furthermore, we were able to generate BAFF-R CAR T cells from small blood samples collected from CLL patients and then demonstrated the cytotoxic effects of these patient-derived CAR T cells against autologous tumor cells. Given these promising results, BAFF-R CAR T-cell therapy has the potential to meet the long-standing need for an effective treatment on CLL patients.

Microbial cell-free DNA-sequencing as an addition to conventional diagnostics in neonatal sepsis.

Bloodstream infections remain a challenge for neonatologists, as traditional culture-based methods are time-consuming and rely on adequate blood volume. Next-generation sequencing (NGS) offers an alternative, as it can identify microbial cell-free DNA (mcfDNA) in a small blood sample, providing rapid pathogen detection. This study aimed to assess the diagnostic performance of DISQVER®-NGS compared to blood cultures in neonatal patients with suspected sepsis. In neonates with suspected sepsis, blood cultures and samples for NGS were prospectively collected. Patients were divided into four categories: 1) sepsis, blood culture positive, 2) clinical sepsis, culture negative, 3) suspected sepsis, 4) validation cohort. NGS detected bacterial, viral or fungal mcfDNA in 24 of 82 samples. Blood cultures were collected in 46 of 84 patients (15/46 positive). DISQVER® correctly identified pathogens in 9/15 patients with a positive blood culture, two with intrinsic resistance to their antibiotic regimen. In seven samples NGS reported the mcfDNA of bacteria that could have theoretically grown in culture but did not. NGS may enhance sensitivity in sepsis diagnostics by detecting mcfDNA in neonates with suspected sepsis. Interpreting NGS results requires correlation with clinical data, laboratory values, and routine microbiological tests for a comprehensive understanding of the patient's condition. Conventional blood culture methods have limitations in accuracy and turnaround time. The study aimed to investigate the diagnostic performance of the Next-Generation Sequencing method DISQVER® compared to traditional blood cultures in neonatal patients with suspected sepsis. Our findings suggest that NGS has the potential to augment the precision of conventional diagnostic techniques, can lead to improved detection of pathogens and targeted treatment approaches in neonatal sepsis. It is emphasized that further validation and integration with clinical and microbiological data are required to ensure optimal clinical utility.

An explainable Artificial Intelligence software system for predicting diabetes

Implementing diabetes surveillance systems is paramount to mitigate the risk of incurring substantial medical expenses. Currently, blood glucose is measured by minimally invasive methods, which involve extracting a small blood sample and transmitting it to a blood glucose meter. This method is deemed discomforting for individuals who are undergoing it. The present study introduces an Explainable Artificial Intelligence (XAI) system, which aims to create an intelligible machine capable of explaining expected outcomes and decision models. To this end, we analyze abnormal glucose levels by utilizing Bi-directional Long Short-Term Memory (Bi-LSTM) and Convolutional Neural Network (CNN). In this regard, the glucose levels are acquired through the glucose oxidase (GOD) strips placed over the human body. Later, the signal data is converted to the spectrogram images, classified as low glucose, average glucose, and abnormal glucose levels. The labeled spectrogram images are then used to train the individualized monitoring model. The proposed XAI model to track real-time glucose levels uses the XAI-driven architecture in its feature processing. The model's effectiveness is evaluated by analyzing the performance of the proposed model and several evolutionary metrics used in the confusion matrix. The data revealed in the study demonstrate that the proposed model effectively identifies individuals with elevated glucose levels.

GENETIC ABLATION OF THE C-TYPE LECTIN RECEPTOR CLEC2D INCREASES PERITONITIS MORTALITY, INFLAMMATION, AND PHYSIOLOGY WITHOUT DIMINISHING ORGAN INJURY.

Background: Sepsis accounts for substantial morbidity and mortality motivating investigators to continue the search for pathways and molecules driving the pathogenesis of the disease. The current study examined if the novel C-type lectin receptor (CLR), Clec2d, plays a significant role in the pathogenesis of sepsis. Methods: Clec2d knockout (KO) mice were fully backcrossed onto the C57/BL6 background. Acute endotoxemia was induced with an intraperitoneal injection of lipopolysaccharide (LPS). Sepsis was induced in two different models, cecal ligation and puncture (CLP) and Pseudomonas aeruginosa pneumonia. Both models were treated with antibiotics and fluid resuscitation. In the sepsis models, physiologic and hematologic measurements were measured at 24 h by collecting a small sample of peripheral blood. Mortality was followed for 14 days. Results : A total of 197 mice were studied, 58 wild type (WT) and 54 knock-out (KO) in the LPS model; 27 wild type and 21 KO mice in the CLP model; and 22 WT and 15 KO mice in the pneumonia model. Clec2d KO mice had greater mortality in the LPS and CLP studies but not the pneumonia model. There were significant differences in multiple parameters determined 24 h post sepsis between mice who subsequently died and those lived. Consistent with previous reports in the CLP model, higher concentrations of IL-6, increased numbers of peripheral blood lymphocytes and greater renal injury were found in the dying mice. In contrast, in the pneumonia model, IL-6 was higher in the surviving mice; however, the IL-6 levels in the pneumonia model (0.6 ± 0.3 ng/mL mean ± SEM) were less than 2% of the IL-6 levels of mice that died in the CLP model (41 ± 9 ng/mL, mean ± SEM). There were no differences in the lymphocyte count or renal injury between living and dying mice in the pneumonia model. In both sepsis models, dying mice had lower heart rates, respiratory rates, and body temperatures. These values were also lower in the KO mice compared to the WT in CLP, but the breath rate and body temperature were increased in the KO pneumonia mice. Conclusion: The C-type lectin receptor Clec2d plays a complicated role in the pathogenesis of sepsis, which varies with source of infection as demonstrated in the models used to study the disease. These data highlight the heterogeneity of the responses to sepsis and provide further evidence that a single common pathway driving sepsis organ injury and death likely does not exist.

Tick-borne pathogens isolated from ticks, rodents, and a shrew in Gangwon and Gyeonggi provinces in the Republic of Korea.

The prevalence of tick-borne pathogens (TBP), Orientia tsutsugamushi, Rickettsia and Borrelia spp. in wild small animals, namely wild rodents, is now widely investigated. This study is to present the prevalence and distribution of O. tsutsugamushi, Rickettsia and Borrelia spp. in wild small animals and ticks collected from Gyeonggi and Gangwon provinces, Republic of Korea (ROK) in 2014. A total of 131 wild small animals, rodents and shrews, and 2,954 ticks were collected from Gyeonggi and Gangwon provinces from May to November 2014. The wild small animals (KR1-9) and ticks (K1-17) were grouped in accordance with capture dates and locations. Among the wild small animals, a total of 393 tissues and blood samples were extracted from six selected small animal series (KR1-3, KR6-8). Also, each date and location-grouped ticks were identified for its species and pooled according to the stage of development. Molecular identification for Rickettsia, Orientia, and Borrelia species was performed using polymerase chain reaction (PCR). To detect TBPs among wild small animals and ticks, primer sets targeting the 56 kDa protein encoding gene of Orientia spp., outer membrane protein B gene (OmpB) of Rickettsia spp., and 5S-23S intergenic spacer region (IGS) gene of Borrelia spp. were used. Of the 393 wild small animals' blood and tissue samples, 199 (50.6%) were positive for Orientia spp., 158 (40.2%) were positive for Borrelia spp., and 55 (14.0%) were positive for Rickettsia spp. Moreover, a total of 14 tick pools (n = 377) was positive for Rickettsia spp. (n=128, 34.0%) and Borrelia spp. (n=33, 8.8%). High prevalence of Orientia spp. and Rickettsia spp. in rodents and shrews were observed. This study presents significant insights by presenting data collected in 2014 that the prevalence of TBP was already high in mid 2010s. This study highlights the sustainable routine surveillance model for TBP.

Quantitation of circulating short-chain fatty acids in small volume blood samples from animals and humans

BackgroundThe role of gut microbiota in human health has been intensively studied and more recently shifted from emphasis on composition towards function. Function is partly mediated through formed metabolites. Short-chain fatty acids (SCFAs) such as acetate, propionate, and butyrate as well as their branched analogues represent major products from gut fermentation of dietary fibre and proteins, respectively. Robust and high-throughput analysis of SCFAs in small volume blood samples have proven difficult. Major obstacles come from the ubiquitous presence of SCFAs that leads to contaminations and unstable analytical results because of the high volatility of these small molecules. Comprehensive and comparable data on the variation of SCFAs in blood samples from different blood matrices and mammal species including humans is lacking. Therefore, our aim was to develop and evaluate a stable and robust method for quantitation of 8 SCFAs and related fermentation products in small volume blood plasma samples and to investigate their variation in humans and different animal species. ResultsDerivatization was a successful approach for measurement of SCFAs in biological samples but quenching of the derivatization reaction was crucial to obtain long-term stability of the derivatized analytes. In total 9 compounds (including succinic acid) were separated in 5 min. The method was linear over the range 0.6–3200 nM formic (FA), acetic (AA), 0.3–1600 nM propionic (PA), and 0.16–800 nM for butyric (BA)-, isobutyric (IBA)-, valeric (VA)-, isovaleric (IVA)-, succinic (SA) and caproic acid (CA). The precision ranged ≤12 % within days and ≤28 % between days (except for CA and VA) in three different plasma quality control (QC) samples (29 batches analyzed over 3 months). The extraction recovery was on average 94 % for the different SCFAs. Typical interquartile range (IQR) concentrations (μM) of SCFAs in human plasma samples were 168 μM (FA), 64 μM (AA), 2.2 μM (PA), 0.54 μM (BA), 0.66 μM (IBA), 0.18 μM (VA), 0.40 μM (IVA), and 0.34 μM (CA). In total, 55 samples per batch/day were successfully analyzed and in total 5380 human plasma samples measured over a 3-year timespan. SignificanceThe developed UHPLC-MS based method was suitable for measuring SCFAs in small blood volume samples and enabled robust quantitative data.

ТРАНСФОРМАЦИЯ ЗДОРОВЬЕСБЕРЕГАЮЩИХ ТЕХНОЛОГИЙ НА ПРИМЕРЕ МОНИТОРИНГА УРОВНЯ ГЛЮКОЗЫ КРОВИ. ЛИТЕРАТУРНЫЙ ОБЗОР

In recent years, there has been a steady increase in the number of people with chronic non-communicable diseases and premature death due to a sedentary lifestyle and decreased physical activity. Studying the consequences of physical inactivity is justified to obtain irrefutable evidence of the relationship between such behavior and the increasing prevalence of obesity and diabetes. The incidence of diabetes is growing at an alarming rate and regular monitoring of glucose levels is critical to combating diabetes complications in the era of developing health-saving technologies. Currently, glucose level in the body is measured invasively by determining it in a small blood sample, usually taken from the fingertip and placed on a disposable test strip. Therefore, there is a need for non-invasive continuous glucose monitoring. Researchers' innovations in the field of non-invasive continuous glucose monitoring using sensors are based on various approaches and are mainly associated with the development of analyzers that can be integrated into a constantly worn device. This review article presents the latest advances in health-saving technologies for diabetes.

Sex and season influence behaviour and physiology of lake trout following angling.

Catch-and-release angling exposes fish to challenges that may result in sub-lethal effects or mortality. Lake trout (Salvelinus namaycush) undergo high rates of release because of size-based harvest regulations or voluntary angler behaviour. Here, we examine short-term impairment in lake trout angled during the summer (n = 74) and fall spawning period (n = 33) to inform best practices for angling. Immediately following capture or 0.5h post-capture, fish underwent reflex and barotrauma assessments, and a small blood sample was collected. Fish were also fitted with an externally mounted biologger equipped with depth, temperature and tri-axial acceleration sensors, that was tethered to allow retrieval of the logger after 14min. In the summer, reflex impairment and barotrauma at 0 and 0.5h were significantly correlated. Loss of orientation and bloating were the most observed indicators. Larger fish and those captured at increased depth had higher barotrauma scores, while prolonged fight times decreased the barotrauma score regardless of sampling time. Plasma cortisol, lactate and glucose increased 0.5h after capture, and extracellular and intracellular pH decreased, all signs that angling was inducing a metabolic response. However, no relationships were found between blood indices and mortality (18.9%). The time required to reach maximum depth after release was longer for fish with increased air exposure but shorter for those with longer fight times. During the fall, fish displayed no mortality or reflex impairment. Anal prolapse was the most observed indicator of barotrauma but only observed in females. Blood indices were most altered 0.5h after capture, with increased cortisol values for fish that were female, particularly large or captured at deeper depth. Locomotor activity was highest for males and increased with depth. Together, our findings suggest that the effects of catch-and-release angling may be dependent on several factors, including sex, season and angling depth.

Use of an expert elicitation methodology to compare welfare impacts of two approaches for blood sampling European badgers (Meles meles) in the field.

In the UK and Republic of Ireland, the European badger (Meles meles) is considered the most significant wildlife reservoir of the bacterium Mycobacterium bovis, the cause of bovine tuberculosis (bTB). To expand options for bTB surveillance and disease control, the Animal and Plant Health Agency developed a bespoke physical restraint cage to facilitate collection of a small blood sample from a restrained, conscious badger in the field. A key step, prior to pursuing operational deployment of the novel restraint cage, was an assessment of the relative welfare impacts of the approach. We used an established welfare assessment model to elicit expert opinion during two workshops to compare the impacts of the restraint cage approach with the only current alternative for obtaining blood samples from badgers in the field, which involves administration of a general anaesthetic. Eleven panellists participated in the workshops, comprising experts in the fields of wildlife biology, animal welfare science, badger capture and sampling, and veterinary science. Both approaches were assessed to have negative welfare impacts, although in neither case were overall welfare scores higher than intermediate, never exceeding 5-6 out of a possible 8. Based on our assessments, the restraint cage approach is no worse for welfare compared to using general anaesthesia and possibly has a lower overall negative impact on badger welfare. Our results can be used to integrate consideration of badger welfare alongside other factors, including financial cost and efficiency, when selecting a field method for blood sampling free-living badgers.

Analysis of Non-Invasive Devices and Techniques Involved in Continuous Monitoring of Interstitial Glucose of Patients with Type 1 Diabetes

Abstract: There are 422 million diabetes patients worldwide according to 2023 census of WHO, and around 100 million cases in India. 8.4 million type 1 diabetes cases were recorded as of 2021. By 2040, it is projected that the number of people living with Type 1 Diabetes will reach 13.5–17.4 million. The surge in diabetes cases has created the critical need for regular glucose monitoring to effectively manage this prevalent health issue. Currently, glucose levels are predominantly measured invasively by pricking the finger for a blood sample and involves invasive methods, such as fingertip pricks, which can be uncomfortable and inconvenient, particularly for paediatric patients. This method utilizes blood glucose monitoring devices, which measure sugar levels in a small blood sample placed on a disposable test strip and have a certain degree of inaccuracy. Patients do not test as often as they should because of the pain and hassle of finger pricks and many do not achieve optimal glycaemic control. However, the shift toward non-invasive continuous glucose monitoring is becoming increasingly imperative and a promising alternative. With current biotechnological advances, many techniques offer a non-invasive, continuous means of monitoring glucose levels and have garnered significant attention in recent years. The objective is to consolidate and summarize recent advancements in non-invasive continuous glucose monitoring, emphasizing integration into wearable platforms for seamless and real-time monitoring. Furthermore, paediatric patients with Type 1 Diabetes face elevated risks of severe hypoglycaemic and hyperglycaemic events due to challenges in glycaemic control. Frequently, monitoring blood glucose is crucial to mitigate these risks and achieve optimal glycaemic management. The objective of ongoing research is to validate AI-based algorithms utilizing ECG signals collected through non-invasive devices to detect glycaemic events. These advancements, once commercially available, have the potential to revolutionize glucose monitoring, offering a convenient, efficient, and less intrusive approach, particularly benefiting paediatric patients and improving overall healthcare management. Despite substantial research and development, challenges persist, including standardizing sweat collection methods, addressing sample degradation, accounting for variations in sweat composition among individuals, optimizing diverse detection methods, improving glucose detection sensitivity, and ensuring overall commercial viability. Overcoming these challenges is paramount to bridge the gap between research and market availability, paving the way for a technological revolution in glucose monitoring. In this study, we compared potential non-invasive glucose monitoring devices and techniques to evaluate the most accurate, pain-free, fast, and cost-friendly device. Upon examination and survey, we have theorized the drawbacks persisting in the existing devices and hypothesized techniques. Looking forward this study has a broader application in not only understanding the limitations and creating more accurate devices but also in continuous glucose monitoring for diabetic patient care.

Parallelized Immunomagnetic Isolation of Basophils Directly from Whole Blood.

Basophils are the rarest circulating white blood cells (WBCs), but they play important roles in allergic disorders and other diseases. To enhance diagnostic capabilities, it would be desirable to isolate and analyze basophils efficiently from small blood samples. In 100 μL of whole blood, there are typically ~103 basophils, outnumbered by ~105 WBCs and ~108 red blood cells (RBCs). Basophils' low abundance has therefore presented a significant challenge in their isolation from whole blood. Conventional in-bulk basophil isolation methods require lengthy processing steps and cannot work with small volumes of blood. Here we report a parallelized integrated basophil isolation device (pi-BID) for the negative immunomagnetic selection of basophils directly from 4 samples of 100 μL of whole blood, in parallel, within 14 minutes including sample preparation time. The pi-BID interfaces directly with standard sample tubes, and uses a single pressure source to drive the flow in parallel microfluidic channels. Compared with conventional in-bulk basophil isolation, the pi-BID is >3× faster, and has higher purity (~93%) and similar recovery (~67%). Compared with other microfluidic devices for the immunomagnetic isolation of WBC sub-types, our pi-BID achieves 10× higher enrichment of target cells from whole blood, with no prior removal of RBCs necessary.

A-380 Concordance of Truvian's Point-of-Care Blood Testing Analyzer to Central Laboratory Testing

Abstract Background Truvian has developed a fully automated blood testing analyzer (TruAnalyzer) capable of running a panel of clinical chemistry, immunoassay and hematology assays from a low-volume blood sample. Truvian's compact instrument was designed to deliver a convenient and affordable alternative to off-site traditional labs, providing lab-accurate rapid insights from a single, small sample of blood with no upfront pre-processing required to inform health decisions at the point of care. Here, we evaluate the precision and accuracy of a comprehensive wellness panel tested on the TruAnalyzer and compare its performance to FDA cleared devices. Methods TruAnalyzer performance was assessed for both precision and accuracy. For the precision studies, two commercially available controls (one for plasma-based assays and one for blood-based assays) were added to the Truvian consumables and loaded into the TruAnalyzer. Six replicates were run on each of the ten instruments (N = 60). Coefficient of variance (CV) analysis was performed and compared against pre-established requirements. For method comparison studies, 50 unique donors were consented and enrolled in an IRB approved study and 68 donor samples were collected over a 3-day period. For each donor, three 4-mL tubes of blood were drawn: 1) a Lithium Heparin (LiHep) sample for the TruAnalyzer clinical chemistry and hematology panel, 2) a LiHep gel tube for the Roche Cobas c311 clinical chemistry assays, and 3) an EDTA sample for the Sysmex PocH-100i complete blood count with 3-part differential. All samples were processed within 1 hour of collection. Using only 300 µL sample volume, the TruAnalyzer reported results for 23 analytes including CMP (no electrolyes), Lipid, HbA1c, and CBC with 3-part differential. Concordance to comparator devices was determined by Bland-Altman analysis. Results For the precision study, 13 out of 14 (93%) chemistry analytes had a between-system CV of ≤5.8%. For hematology, 5 out of 5 (100%) analytes had a between-system CV of ≤6%. For the method comparison study, RBC counts showed 98% of samples tested being within 6% of comparator values. WBC and platelet counts had 97% of samples tested being within 10% and 15% of comparator values respectively. 95% of hematocrit samples were within 6% of comparator values and 98% of hemoglobin samples were within 7% of comparator values. All hematology analytes showed equivalency to Sysmex PocH-100i as determined by Bland-Altman equivalency analysis. For clinical chemistry analytes, 14 out of 15 (93%) analytes showed equivalency to Roche Cobas c311 as determined by Bland-Altman equivalency analysis when CLIA ATE guidelines were applied. 7 out of 15 clinical chemistry analytes had ≥90% of results within ATE. 5 out of 15 clinical chemistry analytes had ≥80% of results within ATE. Conclusion The Truvian blood testing analyzer is the first multi-modality system capable of running hematology, clinical chemistry and immunoassays from a single, low-volume blood sample. Results from this study demonstrate good precision for the majority of panel analytes and excellent concordance to FDA cleared comparators for assays evaluated in this study.

B-043 Thermal Evaluation and Field Study of Labcorp TrueThermTMpackaging System for Protecting Sub-Milliliter Blood Samples

Abstract Background Many diagnostic assays require temperature-controlled sample storage and shipment to ensure accuracy. Here we present, the Labcorp TrueTherm, designed for thermal-controlled shipment of small volume blood samples. The reusable TrueTherm combines a stainless steel vacuum bottle with a custom internal cold pack and insulating stopper. Users refrigerate the cold pack to protect against warm or cold temperature excursions. The whole system is relatively compact, measuring about 10in (25cm) in length, 3 inches (8cm) in diameter, and 2.5 pounds (1kg) in weight. Methods In order to evaluate thermal performance, the TrueTherm system was exposed to both ISTA-7D summer and winter conditions and internal temperature was recorded for 96hrs. Subsequently, venous blood samples were collected from n = 40 subjects, and immediately aliquoted into BD SST (Serum separator) Microtainers®. For each subject, sub-samples were subjected to centrifugal separation (provided by the Labcorp TrueSpinTM battery-powered centrifuge), serum removal, and 24hr insulated shipping on ice packs compared to a variety of 72hr cross-country shipping conditions with and without centrifugal separation and with and without insulated packaging (including TrueTherm) during August 2022. Results TrueTherm maintained temperature between 2 and 20C for 72hrs under simulated summer and winter conditions. Under actual cross-country summer commercial shipping conditions, both centrifugal separation and thermal control via TrueTherm expanded the number of valid analytes compared to unprotected whole blood (see Table 1). Conclusion The results suggest that TrueTherm is an effective system for protecting small blood samples from thermal extremes during extended shipping. Portable thermal moderation was complimentary with portable centrifugal separation to maximize stability of common analytes.

Validation of RP-HPLC UV method for determination ketoconazole in rabbit plasma: An application to the pharmacokinetic study

Ketoconazole is an imidazole broad-spectrum antifungal agent used for systemic and local infections. The pharmacokinetic information for ketoconazole is relatively limited. The validated method for determining ketoconazole in plasma rabbit is not yet reported. The HPLC-UV method is simple, rapid, cost-effective, sensitive, and only requires a small blood sampling. The chromatographic system consisted of a reversed-phase C18 column (250 x 4.6 mm, 5 µm) at a flow rate of 1 ml/min and detection wavelength of 240 nm, and the retention time of about 5 minutes for ketoconazole and 11 min for itraconazole as internal standard. The calibration curve presented linearity in the 0.05-8 µg/ml with R2=0.9969, which indicated good linearity. The method's precision was obtained by intra-day and inter-day repeatability studies, and accuracy was examined by %diff. The result is

Antibody There? Mapping the Human Proteome with Mathias Uhlén

Antibody There? Mapping the Human Proteome with Mathias Uhlén

Assessing the chronic hepatitis B adaptive immune response by profiling specific T-cell receptor repertoire

Challenges in assessing hepatitis B virus (HBV)-specific T cell immunity as an immunological biomarker still remain in chronic hepatitis B (CHB), such as the requirement of large quantities of cells. This study aims to conveniently assess HBV-specific T cells immunity in chronic HBV infected patients. We obtained T cell receptor β chains (TCRβs) from public databases and six acute hepatitis B patients to establish an HBV-specific TCRβs dataset. For some TCRs from one acute patient, their specificities and epitopes were verified. The potential HBV-specific TCRβs from CHB patients were analyzed using GLIPH2 and established dataset. By analyzing two antiviral therapy cohorts including 42 CHB patients, we showed that individuals with better therapy response may depend more on newly emerging potential HBV-specific TCRβs. In a cross-sectional study containing 207 chronic HBV infected patients, the results exhibited that the characteristics of potential HBV-specific clusters were divergent between CHB and hepatocellular carcinoma patients. Our strategy could profile potential HBV-specific TCRβ repertoire using a small blood sample, which will complement traditional methods for assessing the HBV-specific T cell immunity.

Smartphone-based point-of-care anemia screening in rural Bihar in India

BackgroundThe high prevalence of anemia in resource-constrained settings calls for easy-to-use, inexpensive screening tools. The Sanguina Smartphone App, an innovative tool for non-invasive hemoglobin estimation via color-sensitive, algorithm-based analysis of fingernail bed images, was validated in the United States. This study evaluates the performance of the App in a population with different socio-economic, ethnic, demographic and cultural composition in rural Bihar, India.MethodsFor 272 mainly adult patients of a private health centre, hemoglobin measurement with the App is compared with the gold standard laboratory blood analysis. For a second sample of 179 children attending pre-schools, hemoglobin measurement with the App is compared to the results of the HemoCue Hb 301, a point-of-care device using a small blood sample, serving as the reference standard for field-based settings.ResultsThe App reaches ±4.43 g/dl accuracy and 0.38 g/dl bias of comparator values in the clinic-based sample, and ±3.54 g/dl and 1.30 g/dl, respectively in the pre-school sample. After retraining the algorithm with the collected data, the validity of the upgraded version is retested showing an improved performance (accuracy of ±2.25 g/dl, bias of 0.25 g/dl), corresponding to the results of the original validation study from the United States.ConclusionsThe initial version of the App does not achieve the accuracy needed for diagnosis or screening. After retraining the algorithm, it achieves an accuracy sufficient for screening. The improved version with the potential for further adaptions is a promising easy-to-use, inexpensive screening tool for anemia in resource-constrained point-of-care settings.