Antigen Blood Research Articles

Peculiarities of the format of genetic blood systems in patients with oral lichen planus

The number of patients with oral lichen planus (OLP) has increased due to the raise of aggressive forms of the disease (erosive, ulcerative and hyperkeratotic forms) with a possible risk of malignancy. There are isolated researches which indicate a genetic determinism to OLP, but more often these conclusions are based on insufficiently adequate and out of date methods, which make it impossible to correctly interpret the obtained data. The aim was to identify a genetical predisposition with a programmed risk to the oral lichen planus. The main group – 278 patients with the OLP (aged 26-65 years). The control group – 298 people (blood donors) who didn’t have dental diseases, as well as diseases of internal organs and systems. The groups were homogeneous by gender and age. In our research we used such methods: clinical, radiological, immunogenetic, statistical methods were used. The erosive form of OLP was associated with 0(I) group in 54.2±0.4% of cases, while the hyperkeratotic form was associated with group 0(I) only in 28.7±1.8% of cases. B(ІІІ) and AB(ІB) groups were less often associated with the erosive form of OLP and were observed in 17.3±0.1% and 2.0±0.1% of cases, respectively. The integration of A(ІІ) group in the erosive form of OLP was 30.5±0.1%, but the indicator was higher than in individuals with B(III) and AB(IV) groups. Hyperkeratotic form of OLP was more often observed in A(II) carriers than in 0(I) and was 44.1±0.1% versus 28.7±1.8%, respectively. With blood group B (ІІІ), the relationship with OLP is not traced. Correlative relationship with erythrocyte blood antigens of the ABO system in patients with oral lichen planus was established. Risk groups for the development of erosive and hyperkeratotic forms of lichen planus in patients with gastrointestinal tract pathology O(I)>A(II)>B(III) – with erosive form and A(II)>O(I)>B(III)) – with hyperkeratosis.

Diagnostic Utility of SARS-CoV-2 Nucleocapsid Antigenemia: A Meta-analysis.

Studies of the diagnostic performance of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) nucleocapsid antigen in blood (antigenemia) have reached variable conclusions. The potential utility of antigenemia measurements as a clinical diagnostic test needs clarification. We performed a systematic review of Pubmed, Embase, and Scopus through July 15, 2023, and requested source data from corresponding authors. Summary sensitivity from 16 studies (4543 cases) sampled at ≤14 days of symptoms was 0.83 (0.75-0.89), and specificity was 0.98 (0.87-1.00) from 6 studies (792 reverse transcription polymerase chain reaction-negative controls). Summary sensitivity and specificity for paired respiratory specimens with cycle threshold values ≤33 were 0.91 (0.85-0.95) and 0.56 (0.39-0.73) from 10 studies (612 individuals). Source data from 1779 cases reveal that >70% have antigenemia 2 weeks following symptom onset, which persists in <10% at 28 days. The available studies suffer from heterogeneity, and Omicron-era data are scarce. Nucleocapsid antigenemia currently has limited utility due to limitations of existing studies and lack of Omicron-era data. Improved study designs targeting potential clinical uses in screening, surveillance, and complex clinical decision-making-especially in immunocompromised patients-are needed.

Update on Tissue Factor Detection in Blood in 2024: A Narrative Review.

Tissue factor (TF) is a transmembrane protein essential for hemostasis. Different forms of active TF circulate in the blood, either as a component of blood cells and extracellular vesicles (EVs) or as a soluble plasma protein. Accumulating experimental and clinical evidence suggests that TF plays an important role in thrombosis. Many in-house and commercially available assays have been developed to measure TF-dependent procoagulant activity or antigen in blood and have shown promising results for the prediction of disease outcomes or the occurrence of thrombosis events in diseases such as cancer or infectious coagulopathies. This review addresses the different assays that have been published for measuring circulating TF antigen and/or activity in whole blood, cell-free plasma, and EVs and discusses the main preanalytical and analytical parameters that impact results and their interpretation, highlighting their strengths and limitations. In the recent decade, EVTF assays have been significantly developed. Among them, functional assays that use a blocking anti-TF antibody or immunocapture to measure EVTF activity have higher specificity and sensitivity than antigen assays. However, there is still a high variability between assays. Standardization and automatization are prerequisites for the measurement of EVTF in clinical laboratories.

Prevalence and Risk Factors of Alloimmunization in Multi-Transfused Pediatric Patients: A Cross-Sectional Study from a Sub-Himalayan Tertiary Care Hospital in Uttarakhand India

BackgroundPacked red blood cell (PRBC) transfusion is critical in managing pediatric patients with conditions requiring frequent transfusions, such as leukemia, thalassemia, and bone marrow disorders. Alloimmunization, the formation of antibodies against foreign antigens in donor blood, is a significant complication of repeated transfusions. Further, auto/alloimmunization is influenced by multiple factors, including antigenic differences between donor and recipient and the recipient’s immune status. ObjectivesThis study aimed to assess the prevalence and risk factors of auto/alloimmunization among pediatric patients requiring multiple PRBC transfusions in a tertiary care hospital in the sub-Himalayan region of Uttarakhand, India. MethodsA cross-sectional study was conducted on multiply transfused 113 pediatric patients aged 4 months to 18 years who received more than one PRBC transfusion between September 2022 and August 2023. Antibody screening and identification were performed using column agglutination techniques. Statistical analysis was conducted to evaluate associations between demographic, clinical factors, and antibody detection. ResultsAlloimmunization was observed in 5.31% of patients, with the majority developing antibodies against the MNS blood group system. Autoantibodies were more common, detected in 17.7% of patients. Significant associations were found between the history of prior PRBC transfusions and the presence of alloantibodies (p=0.005). Age, gender, and ethnicity did not show a statistically significant association with antibody detection. ConclusionsThe study reveals a relatively higher prevalence of autoimmunization among multi-transfused pediatric patients. The history of PRBC transfusions was a significant risk factor, indicating the need for extended RBC phenotyping and tailored transfusion strategies to reduce alloimmunization risks in these patients. Most patients and blood donors in this region belong to the local Garhwali community. This homogeneity may help explain the lower rate of alloimmunization observed, suggesting a degree of antigenic similarity among the blood donors and the recipients.

Enhancing Pregnancy Care: Harnessing Label‐Free Immunosensors for Pre‐Eclampsia Detection Using PdNPs/Poly(3,5‐Diaminobenzoic Acid) Modified Glassy Carbon Electrodes

AbstractPlacental Growth factor (PlGF) is one of the biomarkers useful for detecting pregnancy hypertension disorder, Pre‐eclampsia. Herein, we focus on developing a label‐free immunosensor using simple electrochemical methods to detect PlGF antigens for pre‐eclampsia diagnosis. The work includes the electrochemical deposition of Palladium nanoparticles (PdNPs) on the glassy carbon electrode (GCE) surface using amperometry followed by electropolymerization of diaminobenzoic acid (DABA) onto the PdNPs/GCE. Antibody (aPlGF) was covalently immobilized on the pDABA/PdNPs/GCE using EDC/NHS reaction. The interaction of the antibody with the antigen was measured using differential pulse voltammetric technique. The linear range obtained for the immunosensor is 1–25 ng mL−1 with a limit of detection of 53 pg mL−1. The stability and reproducibility of the sensor were obtained in the acceptable range. The developed sensor was used to detect PlGF antigen in artificial blood and urine samples by spike recovery analysis.

Cytokeratin 18 as a Novel Biomarker in Patients with Hypertrophic Cardiomyopathy.

Hypertrophic cardiomyopathy (HCM) is a heart muscle disease associated with an increased risk for sudden cardiac death (SCD). Cytokeratin 18-based proteins, such as M30 and M65 antigens, are known cell-death biomarkers. M30 antigen is released from cells during apoptosis, and M65 antigen is released during cell death from any cause, such as apoptosis or necrosis. We aimed to study the expression of M30 and M65 antigens in peripheral blood obtained by 46 HCM patients and compare with 27 age- and sex-matched patients without HCM. We also investigated the CK18 expression in myocardium from postmortem HCM hearts. M30 and M65 antigens were significantly increased in the HCM vs. non-HCM group (Μ30: 338 ± 197 U/uL vs. 206 ± 166 U/uL, p = 0.003; M65: 428 ± 224 U/uL vs. 246 ± 214 U/uL, p = 0.001), and HCM patients with a higher expression of these markers (M30: 417 ± 208 vs. 271 ± 162 U/uL, p = 0.011; M65: 518 ± 242 vs. 351 ± 178 U/uL, p = 0.011) had a higher risk for SCD. In HCM, both apoptosis and necrosis are increased, but particularly necrosis (M30/M65 ratio: 0.75 ± 0.09 vs. 0.85 ± 0.02, p < 0.001). CK18 is expressed in the HCM myocardium (1.767 ± 0.412 vs. 0.537 ± 0.383, % of area, p = 0.0058). Therefore, M30 and M65 antigens may be novel biomarkers in HCM.

Assessment of CD8+ T-cell mediated immunity in an influenza A(H3N2) human challenge model in Belgium: a single centre, randomised, double-blind phase 2 study

Protection afforded by inactivated influenza vaccines can theoretically be improved by inducing T-cell responses to conserved internal influenza A antigens. We assessed whether, in an influenza controlled human infection challenge, susceptible individuals receiving a vaccine boosting T-cell responses would exhibit lower viral load and decreased symptoms compared with placebo recipients. In this single centre, randomised, double-blind phase 2 study, healthy adult (aged 18-55 years) volunteers with microneutralisation titres of less than 20 to the influenza A(H3N2) challenge strain were enrolled at an SGS quarantine facility in Antwerp, Belgium. Participants were randomly assigned double-blind using a permuted-block list with a 3:2 allocation ratio to receive 0·5 mL intramuscular injections of modified vaccinia Ankara (MVA) expressing H3N2 nucleoprotein (NP) and matrix protein 1 (M1) at 1·5 × 108 plaque forming units (4·3 × 108 50% tissue culture infectious dose [TCID50]; MVA-NP+M1 group) or saline placebo (placebo group). At least 6 weeks later, participants were challenged intranasally with 0·5 mL of a 1 × 106 TCID50/mL dose of influenza A/Belgium/4217/2015 (H3N2). Nasal swabs were collected twice daily from day 2 until day 11 for viral PCR, and symptoms of influenza were recorded from day 2 until day 11. The primary outcome was to determine the efficacy of MVA-NP+M1 vaccine to reduce the degree of nasopharyngeal viral shedding as measured by the cumulative viral area under the curve using a log-transformed quantitative PCR. This study is registered with ClinicalTrials.gov, NCT03883113. Between May 2 and Oct 24, 2019, 145 volunteers were enrolled and randomly assigned to the MVA-NP+M1 group (n=87) or the placebo group (n=58). Of these, 118 volunteers entered the challenge period (71 in the MVA-NP+M1 group and 47 in the placebo group) and 117 participants completed the study (71 in the MVA-NP+M1 group and 46 in the placebo group). 78 (54%) of the 145 volunteers were female and 67 (46%) were male. The primary outcome, overall viral load as determined by quantitative PCR, did not show a statistically significant difference between the MVA-NP+M1 (mean 649·7 [95% CI 552·7-746·7) and placebo groups (mean 726·1 [604·0-848·2]; p=0·17). All reported treatment emergent adverse events (TEAEs; 11 in the vaccination phase and 51 in the challenge phase) were grade 1 and 2, except for two grade 3 TEAEs in the placebo group in the challenge phase. Agrade 4 second trimester fetal death, considered possibly related to the MVA-NP+M1 vaccination, and an acute psychosis reported in a placebo participant during the challenge phase were reported. The use of an MVA vaccine to expand CD4+ or CD8+ T cells to conserved influenza A antigens in peripheral blood did not affect nasopharyngeal viral load in an influenza H3N2 challenge model in seronegative, healthy adults. Department of Health and Human Services; Administration for Strategic Preparedness and Response; Biomedical Advanced Research and Development Authority; and Barinthus Biotherapeutics.

Neighborhood ethnic density and disparities in proximal blood donation opportunities.

Despite being the largest racial/ethnic minority group in the United States, Hispanic/Latinos (H/L) are significantly underrepresented among blood donors. A lack of proximal blood donation opportunities may be one factor contributing to these disparities. However, few studies have investigated this possibility. Proprietary data on mobile blood collections in Maricopa County, Arizona, were gathered for the period of January 01, 2022 to April 30, 2022 and paired with census tract information using ArcGIS. Maricopa County encompasses the city of Phoenix with a total population of approximately 4.5 million people, including 1.5 million H/L residents. Blood drive count was regressed on H/L ethnic density and total population, and model estimates were exponentiated to obtain odds ratios (ORs) and 95% confidence intervals (CIs). During the specified period, approximately 27,000 red blood cell units were collected through mobile drives. Consistent with expectations, when controlling for total neighborhood population, each 10% increase in H/L ethnic density lowered the odds of having a blood drive in the corresponding neighborhood by 12% (OR = 0.88, 95% CI (0.83, 0.92), p < .001). These findings provide initial evidence of fewer proximal donation opportunities in areas with greater H/L population density which may contribute to H/L underrepresentation in blood donation and the need for more inclusive collection efforts. Improved access to blood collection is modifiable and could help to increase the overall blood supply, enhance the ability to successfully match specific blood antigen needs of an increasingly diverse population, and bring about a more resilient blood system.

SARS-CoV-2 RNA and Nucleocapsid Antigen Are Blood Biomarkers Associated With Severe Disease Outcomes That Improve in Response to Remdesivir.

Although antivirals remain important for the treatment COVID-19, methods to assess treatment efficacy are lacking. Here, we investigated the impact of remdesivir on viral dynamics and their contribution to understanding antiviral efficacy in the multicenter Adaptive COVID-19 Treatment Trial 1, which randomized patients to remdesivir or placebo. Longitudinal specimens collected during hospitalization from a substudy of 642 patients with COVID-19 were measured for viral RNA (upper respiratory tract and plasma), viral nucleocapsid antigen (serum), and host immunologic markers. Associations with clinical outcomes and response to therapy were assessed. Higher baseline plasma viral loads were associated with poorer clinical outcomes, and decreases in viral RNA and antigen in blood but not the upper respiratory tract correlated with enhanced benefit from remdesivir. The treatment effect of remdesivir was most pronounced in patients with elevated baseline nucleocapsid antigen levels: the recovery rate ratio was 1.95 (95% CI, 1.40-2.71) for levels >245 pg/mL vs 1.04 (95% CI, .76-1.42) for levels <245 pg/mL. Remdesivir also accelerated the rate of viral RNA and antigen clearance in blood, and patients whose blood levels decreased were more likely to recover and survive. Reductions in SARS-CoV-2 RNA and antigen levels in blood correlated with clinical benefit from antiviral therapy. NCT04280705 (ClinicalTrials.gov).

Polyomavirus-positive Merkel cell carcinoma: the beginning of the beginning.

Merkel cell carcinoma (MCC) is an aggressive, fast-growing, highly metastatic neuroendocrine skin cancer. The Merkel cell polyomavirus (MCPyV) is an oncogenic driver in the majority of MCC tumors. In this issue of the JCI, Hansen and authors report on their tracking of CD8+ T cells reactive to MCPyV T antigen (T-Ag) in the peripheral blood of 26 patients with MCC who were undergoing frontline anti-programmed cell death protein-1 (anti-PD-1) immunotherapy. They discovered unique T cell epitopes and used the power of bar-coded tetramers to portray immune checkpoint inhibitor-induced immunogenicity as a predictor of clinical response. These findings provide the foundation for therapeutic possibilities for MCC, including vaccines and adoptive T cell- and T cell receptor-driven (TCR-driven) treatments.

Overview on utility of in-house tests for detection of systemic infectious diseases in dogs

For detection of infectious diseases, several point-of-care (POC) tests are on the market in addition to methods performed in commercial laboratories. These POC tests are based on enzyme-linked immunosorbent assay (ELISA) or other immunochromatographic technologies and present results within few minutes in veterinary practice. This article gives an overview of the utility of numerous POC tests of different manufacturers for detection of parvovirus antigen in feces, Dirofilaria (D.) immitis antigen in blood as well as antibodies against Borrelia (B.) burgdorferi, Anaplasma (A.) spp., Ehrlichia (E.) spp., Leptospira (L.) spp. and Leishmania (L.) infantum in blood (single or in different combinations). Sensitivity and specificity of these tests are important for their usefulness in veterinary practice. Furthermore, presence of antibodies or detection of antigen has to correlate with the presence of clinical signs. POC tests for detection of canine parvovirus antigen have a very high specificity, the sensitivity of all evaluated POC tests, however, is very low. POC tests for detection of D. immitis antigen have a very high sensitivity and specificity. As they detect antigen from the uterus of female adult parasites, test results are negative when only very few female or only male adults are present. POC tests for detection of antibodies against B. burgdorferi only indicate contact with Borrelia spp. and do not prove clinical Lyme disease, as the infection only extremely rarely causes clinical signs. POC tests for detection of antibodies against A. phagocytophilum are also not suitable for diagnosis of clinical anaplasmosis. Infections with A. phagocytophilum only lead to clinical disease in very rare cases and in these, clinical signs occur before the development of antibodies. POC tests for detection of antibodies against E. canis have a very high sensitivity as well as specificity. POC tests for detection of antibodies against L. infantum and Leptospira species (spp.) show a very high specificity and a high sensitivity. However, Leptospira spp. antibody-positive results may occur following vaccination, as the POC tests cannot distinguish between field and vaccination strains.

SPR and Double Resonance LPG Biosensors for Helicobacter pylori BabA Antigen Detection.

Given the medical and social significance of Helicobacter pylori infection, timely and reliable diagnosis of the disease is required. The traditional invasive and non-invasive conventional diagnostic techniques have several limitations. Recently, opportunities for new diagnostic methods have appeared based on the recent advance in the study of H. pylori outer membrane proteins and their identified receptors. In the present study we assess the way in which outer membrane protein-cell receptor reactions are applicable in establishing a reliable diagnosis. Herein, as well as in other previous studies of ours, we explore the reliability of the binding reaction between the best characterized H. pylori adhesin BabA and its receptor, the blood antigen Leb. For the purpose we developed surface plasmon resonance (SPR) and double resonance long period grating (DR LPG) biosensors based on the BabA-Leb binding reaction for diagnosing H. pylori infection. In SPR detection, the sensitivity was estimated at 3000 CFU/mL-a much higher sensitivity than that of the RUT test. The DR LPG biosensor proved to be superior in terms of accuracy and sensitivity-concentrations as low as 102 CFU/mL were detected.

Role of H.pylori in Chronic Sore Throat by Using H.pylori Line.

Pharyngitis is an inflammation of the mucous membranes of the oropharynx. Pharyngitis may be caused by an infectious or noninfectious disease. Noninfectious diseases of pharynx include allergies, trauma, cancer, reflux and certain toxins. Infection with H. Pylori is associated with developing chronic sore throat, gastritis, gastric or duodenal ulcer, gastric cancer and MALT lymphoma. There are many different investigations to diagnose H pylori as H pylori antigen in blood and stool, urea breath test but, H. Pylori line is a new test for detection of the virulent strains. There are many lines of H pylori therapy in the form of PPIs and antibiotics for about two weeks. This study aimed to detect role of H pylori in chronic pharyngitis. 85 patients who had chronic pharyngitis with normal CBC, WBCS, lymphocyte, monocyte and eosinophils with negative ASO titer and throat swab. These patients did H pylori line to detect H pylori virulent antigen. 77 patients with chronic pharyngitis are positive H pylori and after medical treatment 68 patients became negative. H. Pylori line is a new test for detection of the virulent strains and screening H pylori carrier at risk of developing gastric and duodenal ulcers as well as cancer.

Diatomite-Based, Flexible SERS Immunosensor Platform for Rapid, Specific, and Sensitive Detection of Circulating Cancer-Specific Protein Biomarkers in Serum Using Raman Probes.

Cancer is one of the most actively researched diseases having a high mortality rate when not detected at an early stage. Thus, rapid, simultaneous, and sensitive quantification of cancer biomarkers plays an important role in early diagnosis, with patient impact to disability adjusted life years. Herein, a diatomite-based SERS flexible platform for the rapid and sensitive detection of circulating cancer-specific protein biomarkers in serum is presented. In this approach, diatomite/AgNPs strips with maximum SERS activity prepared using the layer-by-layer (LbL) technique were modified with specific antibodies, and specific antigens (HER2, CA15-3, PSA, and MUC4) were captured and detected. By using Raman probes specific to the captured antigens in serum, a SERS limit of detection (LOD) of 0.1 ng/mL was measured (calculated LOD < 0.1 ng/mL). This value is lower than the cutoff amount of cancer antigens in the person's blood. The specificity for the antigens of each antibody was calculated to be higher than 95%. As a result, an immunosensor for rapid detection of cancer biomarkers in serum with good specificity, high sensitivity, good reproducibility, and low cost has been demonstrated. Overall, we show that the prepared diatomite-based SERS substrate with a high surface-to-volume ratio is a useable platform for immunoassay tests.

SERS-Temperature Dual-Mode T-type Lateral Flow Strip for Accurate Detection of Free and Total Prostate-Specific Antigens in Blood.

Accurate point-of-care (POC) analysis of cancer markers is the essence in the comprehensive early screening and treatment of cancer. Dual-mode synchronous detection is one of the effective approaches to reduce the probability of false negatives or false positives. As a result, this can greatly improve the accuracy of diagnosis. In this work, a surface-enhanced Raman scattering (SERS)-temperature dual-mode T-type lateral flow strip was fabricated to direct and simultaneous POC detection of total and free prostate-specific antigens (t-PSA and f-PSA) in blood. With the advantage of high stability of T-type lateral flow strip and simultaneous acquirement of assay results for t-PSA and f:t PSA ratio, the proposed method has high accuracy in the diagnosis of prostate cancer, especially in the diagnostic gray zone between 4.0 and 10.0 ng/mL. The SERS-temperature dual-signal has a good linear correlation with either f-PSA or t-PSA. To evaluate the clinical diagnostic performance of the proposed method, spiked human serum samples and the whole blood sample were analyzed. The assay results showed good recovery, and compared with traditional electrochemiluminescence immunoassay (ECLIA) method (t-PSA: 43.151; f/t ratio: 0.08), the results obtained by the proposed method were similar (t-PSA: 40.15 (SERS), 36.21 (temperature); f/t ratio: 0.08 (SERS), 0.08 (temperature), but the detection time (15 min) and cost ($0.05) had been greatly reduced. Therefore, the proposed SERS-temperature synchronous dual-mode T-type lateral flow strip has a strong application potential in the field of accurate large-scale diagnostics of prostate cancer on-site by simultaneous POC detection of t-PSA and f-PSA in blood.

MediMer: a versatile do-it-yourself peptide-receptive MHC class I multimer platform for tumor neoantigen-specific T cell detection.

Peptide-loaded MHC class I (pMHC-I) multimers have revolutionized our capabilities to monitor disease-associated T cell responses with high sensitivity and specificity. To improve the discovery of T cell receptors (TCR) targeting neoantigens of individual tumor patients with recombinant MHC molecules, we developed a peptide-loadable MHC class I platform termed MediMer. MediMers are based on soluble disulfide-stabilized β2-microglobulin/heavy chain ectodomain single-chain dimers (dsSCD) that can be easily produced in large quantities in eukaryotic cells and tailored to individual patients' HLA allotypes with only little hands-on time. Upon transient expression in CHO-S cells together with ER-targeted BirA biotin ligase, biotinylated dsSCD are purified from the cell supernatant and are ready to use. We show that CHO-produced dsSCD are free of endogenous peptide ligands. Empty dsSCD from more than 30 different HLA-A,B,C allotypes, that were produced and validated so far, can be loaded with synthetic peptides matching the known binding criteria of the respective allotypes, and stored at low temperature without loss of binding activity. We demonstrate the usability of peptide-loaded dsSCD multimers for the detection of human antigen-specific T cells with comparable sensitivities as multimers generated with peptide-tethered β2m-HLA heavy chain single-chain trimers (SCT) and wild-type peptide-MHC-I complexes prior formed in small-scale refolding reactions. Using allotype-specific, fluorophore-labeled competitor peptides, we present a novel dsSCD-based peptide binding assay capable of interrogating large libraries of in silico predicted neoepitope peptides by flow cytometry in a high-throughput and rapid format. We discovered rare T cell populations with specificity for tumor neoepitopes and epitopes from shared tumor-associated antigens in peripheral blood of a melanoma patient including a so far unreported HLA-C*08:02-restricted NY-ESO-1-specific CD8+ T cell population. Two representative TCR of this T cell population, which could be of potential value for a broader spectrum of patients, were identified by dsSCD-guided single-cell sequencing and were validated by cognate pMHC-I multimer staining and functional responses to autologous peptide-pulsed antigen presenting cells. By deploying the technically accessible dsSCD MHC-I MediMer platform, we hope to significantly improve success rates for the discovery of personalized neoepitope-specific TCR in the future by being able to also cover rare HLA allotypes.

Prospective study of ABO and Rh blood group frequency and distribution among health-care professional students at Hassan Institute of Medical Sciences, Hassan

Background: The presence of immunologically competent agglutinogens in ABO and Rhesus (Rh) system makes these blood groups clinically important. The distribution frequency of these blood groups in various geographical regions is essential for the maintenance of blood bank records, for research studies, etc. This helps in safe transfusion during emergency. Many population-based research works were conducted on the prevalence of blood agglutinogens. The lack of data on these blood antigens among young health-care professional students prompted the conduct of this study on blood groups. Aims and Objectives: The aims and objectives of the study are to ascertain blood group frequencies among health-care professional students and to obtain prospective group of Rh-negative blood donor database. Materials and Methods: Research was accomplished on 400 health-care professional students of HIMS, Hassan, in department of physiology after going through knowledge, attitude, and practice questionnaire. Blood grouping was done by collecting blood from participants by finger prick method on glass slides. Results: In participants, the most common blood group was O (40.8%) with decreasing prevalence of B (34.3%), A (18%), and AB (7%). The frequency of Rh-positive and negative groups was 95.5% and 4.5%, respectively. Conclusion: Among participants, blood group O and blood group AB was most and least common, respectively. The frequency of Rh positive was far higher compared to Rh-negative groups.

A smartphone-based immunochromatographic strip platform for on-site quantitative detection of antigenic targets.

To report the testing signal of an immunochromatographic assay for on-site quantitative detection, a portable and user-friendly smartphone-based biosensing platform is developed in this study. This innovative system is composed of an ambient light sensor inherent smartphone reader and a 3D-printed handhold device, a quantitative tool capable of directly interpreting carbon nanoparticle (CNP)-conjugated immunochromatographic strips. To showcase the platform capability, the smartphone-based immunochromatography system (SPICS) reader and device were successfully used in CNP strips for rapid detection of the early pregnancy marker human chorionic gonadotropin in female urine (HCG; limit of detection [LOD]: 0.30 mIU mL-1), prostate-specific antigen in patient blood (PSA; LOD: 0.28 ng mL-1) and ampicillin residue in animal milk (AMP; LOD: 0.23 ng mL-1). The results were fully correlated with conventional commercial instruments (R2 = 0.99). The SPICS platform exhibits significant advantages, including portability, cost-effectiveness, easy operation, and rapid and quantitative detection, making it a valuable on-site diagnosis tool for use in home and community healthcare facilities.

Prevalence of Risk Factors Associated with Placental Malaria in Observational Study in Kator Primary Health Center South Sudan

Introduction: Civil unrest, public health system fragility and community mass relocation had played major roles in development of Placental Malaria Parasitization. This study aimed to measure and identifies risk factors associated with placental malaria infections in Kator primary health center. Methods and Materials: 115 enrolled pregnant women in cross-section survey after signing consent form using observational technique tools in one year period. ABO, peripheral blood antigen detection for malaria parasites using RDT kits and quantitative questionnaire information were obtained at recruitment phase while second peripheral blood for placental malaria parasites species applying RDT, placental weight and baby weight were measured after delivery as phase two. SPSS version 26 was applied with 0.005% P-value and CI 95%. Results: Out of 115 recruited pregnant women only (86.0%) 99 reached delivery room. With 29 primigravidae, 23 secundigravidae and 47 multigravidae; primigravida OR 95%CI 2.4 (1.73-5.64) P-vale 0.00013 and secundigravida with OR 95% CI1.8 (1.23-2.93) P-value 0.00072 and multigravida with OR 95% CI 1.5 (0.91-3.45) P-value 0.83. untreated bed net with OR 95% CI 1.4 (1.12-3.08) P-value 0.00053 and shared bed net at night with OR 95% CI 7.4(5.18-17.32) P-value 0.00027. Low birth weight, low placental weight and blood group O were not associated with placental malaria. Overall Placental Malaria prevalent was 26.3%. Conclusion: in this study, elevated placental malaria was recorded in Kator area of South Sudan. Doubling efforts to reduce placental malaria infections and its adverse clinical complications a new strategy to control the syndromic effects of the disease is required.

Exploring the naturally acquired response to Pvs47 gametocyte antigen.

Malaria represents a challenging global public health task, with Plasmodium vivax being the predominant parasite in Brazil and the most widely distributed species throughout the world. Developing a vaccine against P. vivax malaria demands innovative strategies, and targeting gametocyte antigens shows promise for blocking transmission prevention. Among these antigens, Pvs47, expressed in gametocytes, has shown remarkable efficacy in transmission blocking. However, remains underexplored in vaccine formulations. This study employed in silico methods to comprehensively characterize the physicochemical properties, structural attributes, epitope presence, and conservation profile of Pvs47. Additionally, we assessed its antigenicity in individuals exposed to malaria in endemic Brazilian regions. Recombinant protein expression occurred in a eukaryotic system, and antigenicity was evaluated using immunoenzymatic assays. The responses of naturally acquired IgM, total IgG, and IgG subclasses were analyzed in three groups of samples from Amazon region. Notably, all samples exhibited anti-Pvs47 IgM and IgG antibodies, with IgG3 predominating. Asymptomatic patients demonstrated stronger IgG responses and more diverse subclass responses. Anti-Pvs47 IgM and IgG responses in symptomatic individuals decrease over time. Furthermore, we observed a negative correlation between anti-Pvs47 IgM response and gametocytemia in samples of symptomatic patients, indicating a gametocyte-specific response. Additionally, negative correlation was observed among anti-Pvs47 antibody response and hematocrit levels. Furthermore, comparative analysis with widely characterized blood antigens, PvAMA1 and PvMSP119, revealed that Pvs47 was equally or more recognized than both proteins. In addition, there is positive correlation between P. vivax blood asexual and sexual stage immune responses. In summary, our study unveils a significant prevalence of anti-Pvs47 antibodies in diverse Amazonian samples and the importance of IgM response for gametocytes depuration. These findings regarding the in silico characterization and antigenicity of Pvs47 provide crucial insights for potential integration into P. vivax vaccine formulations.