Antigen Antibody Research Articles

Impedimetric Biosensors for the Quantification of Serum Biomarkers for Early Detection of Lung Cancer

Lung cancer is the most common type of cancer diagnosed worldwide and is also among the most fatal. Early detection, before symptoms become evident, is fundamental for patients’ survival. Therefore, several lung cancer biomarkers have been proposed to enable a prompt diagnosis, including neuron-specific enolase (NSE) and carcinoembryonic antigen (CEA). NSE and CEA are two serum proteins whose elevated levels have been associated with lung cancer. Hence, in this study, impedimetric biosensors (immunosensors) able to quantify NSE and CEA were developed as proof-of-concept devices for lung cancer diagnosis. The sensing platform exploited for the immunosensors comprises a novel combination of a magnetic platform, screen-printed gold electrode (SPGE), and magnetic nanobeads (MB). The MB were functionalized with antibodies to capture the analyte from the sample and to move it over the sensing area. The immunosensors were then developed by immobilizing another set of antibodies for either CEA or NSE on the SPGE through formation of self-assembled monolayer (SAM). The second set of antibodies enabled a sandwich assay to be formed on the surface of the sensor, while MB manipulation was applied during the sensor performance to depict a microfluidic system and increase antigen–antibody complex formation prior to CEA or NSE detection and quantification. The optimized immunosensors were successfully tested to measure various concentrations of CEA and NSE (0–100 ng/mL) in both phosphate buffer and 100% human serum samples. Clinically relevant detection limits of 0.26 ng/mL and 0.18 ng/mL in buffer and 0.76 ng/mL and 0.52 ng/mL in 100% serum for CEA and NSE, respectively, were achieved via electrochemical impedance spectroscopy with the use of potassium ferri/ferrocyanide as a redox probe. Hence, the two immunosensors demonstrated great potential as tools to be implemented for the early detection of lung cancer.

Antigen–antibody complex density and antibody-induced HLA protein unfolding influence Fc-mediated antibody effector function

Donor-specific antibodies (DSAs) targeting mismatched human leukocyte antigen (HLA) molecules are one of the principal threats to long-term graft survival in solid organ transplantation. However, many patients with long-term circulating DSAs do not manifest rejection responses, suggesting a degree of heterogeneity in their pathogenicity and related functional activity. Immunologic risk stratification of transplant recipients is complicated by challenges intrinsic to defining alloantibody responses that are potentially pathogenic versus those that are not. Thus, a comprehensive understanding of how human alloantibodies target and interact with donor HLA molecules is vital for the development and evaluation of new strategies aimed at reducing antibody-mediated rejection responses. In this study, we employ hydrogen–deuterium exchange–mass spectrometry (HDX–MS), molecular dynamics (MD) simulations, and advanced biochemical and biophysical methodologies to thoroughly characterize a panel of human monoclonal alloantibodies and define the influence of Fc-region biology, antibody binding kinetics, target antigen density, and structural characteristics on their ability to potentiate the forms of immune effector mechanisms that are strongly implicated in transplant rejection. Our findings have significant implications for our understanding of the key biological determinants that underlie the pathogenicity or lack thereof of human alloantibodies.

Enhanced detection of distinct honeycomb-structured neuronal SMARCC2 cytobodies in Parkinson's Disease via Cyclic Heat-Induced Epitope Retrieval (CHIER).

Antigen retrieval is crucial for immunohistochemistry, particularly in formalin-fixed paraffin-embedded brain tissue, where fixation causes extensive crosslinking that masks epitopes. Heat Induced Epitope Retrieval (HIER) reverses these crosslinks, improving access to nuclear and aggregated proteins. We introduce Cyclic Heat-Induced Epitope Retrieval (CHIER), an advanced technique that builds on HIER by incorporating repeated cycles of heating and cooling. CHIER optimises antigen retrieval and significantly improves detection. CHIER is particularly effective for detecting chromatin-binding proteins, such as SMARCC2, which are difficult to label using conventional IHC methods. Using CHIER on formalin-fixed paraffin-embedded human brain sections, we achieved robust detection of SMARCC2 in both the nucleus and cytoplasm. CHIER also enhanced the visualisation of large SMARCC2+ cytoplasmic bodies, termed cytobodies, which are increased in Parkinson's Disease (PD). Our findings suggest that SMARCC2 may translocate from the nucleus to the cytoplasm in PD, potentially implicating SMARCC2 aggregation in the disease's pathology. Furthermore, CHIER does not negatively impact the antigenicity of other antibodies, supporting its use for multiplex fluorescent immunohistochemistry and super-resolution imaging. These results highlight CHIER's potential for improving the detection of chromatin-binding and aggregated proteins in neurodegenerative disease research, offering new insights into SMARCC2's role in Parkinson's Disease.

A label-free liquid crystal-based immunosensor for the detection of indole-3-acetic acid

ABSTRACT Indole-3-acetic acid (IAA), as a critical phytohormone, has positive effects on botanic growth and development. Developed herein is a novel liquid crystal (LC) immunosensor based on the indirect competitive assay format for the detection of IAA. In light of the small molecular weight of antigen IAA, immobilising IAA on the surface of APTES/DMOAP self-assembled membranes by covalent binding has little effect on LC molecular orientation. When anti-IAA was added, anti-IAA specifically bound to immobilised-IAA on the substrate surface, forming an antigen–antibody complex with a large molecular weight, which induced the homeotropic-to-tilted transition of LC, resulting in a change of the optical image from uniformly black to bright under the polarised light. However, when the sample contained free-IAA, the free-IAA would competitively bind to limited anti-IAA with immobilised-IAA on the substrate surface. As the concentration of free-IAA increased, the anti-IAA that could bind to immobilised-IAA gradually decreased, thereby weakening the degree of disturbance to LCs and producing few birefringent textures. The LC-based imaging method had a good signal-to-noise ratio. When the concentration of IAA exceeded 10−8 M, a ‘positive’ response was observed. The proposed sensor exhibited high sensitivity and desirable selectivity, and it was label free and easy to operate.

Outcomes of Hematopoietic Stem Cell Transplantation in Patients With Thalassemia Major: How Do Anti-HLA Antibodies Impact?: The Impact of Anti-HLA Antibodies on Transplantation Outcomes in Thalassemia Major.

To investigate the effects of anti-human Leucocyte Antigen (HLA) antibody positivity on early hematopoietic stem cell transplantation (HSCT) results in patients with thalassemia major (TM). One hundred and twenty-four HLA-matched HSCTs were performed in patients with TM between 2015 and 2022. Ninety-one patients were screened for anti-HLA antibodies by testing panel reactive antigens (PRA). Demographic and transplantation characteristics of patients were recorded. The presence of PRA was tested with the Antibody Testing Assay (Luminex LIFECODES HLA Antibody Identification System). The number of PRA-positive patients was 54. There was no relationship between acute graft versus host disease (GVHD), chronic GVHD, grade of GVHD, and viral reactivation of the patients. However, platelet engraftment took around 3 days longer in the PRA-positive group (p = 0.05). The median number of erythrocyte transfusions was significantly higher in PRA-positive patients in the post-transplant period (p = 0.003), as was the median number of platelet transfusions (p = 0.003). Treosulfan conditioning increased the stable mixed chimerism (MC) rate by 3.8-fold (p = 0.011). In contrast, reduced rates of MC were found in patients who received matched unrelated donor cells or peripherally derived stem cells (p = 0.011 and p = 0.039, respectively) in the posttransplantation period in TM patients. PRA-positivity did not affect MC (p = 0.478). However, 80% of patients who had primary graft failure (n = 5; p = 0.59) and 75% of patients who died (n = 4) were PRA positive (p = 0.64), but these results were statistically insignificant due to the low number of patients. Anti-HLA antibodies primarily delayed platelet engraftment in TM patients and increased the erythrocyte and thrombocyte transfusion requirements. Although PRA positivity was more common in patients with primary graft failure or who died, there was no statistically significant impact of PRA positivity on chimerism, acute or chronic GVHD, viral activation, or mortality rates.

Longitudinal effects of SARS-CoV-2 breakthrough infection on imprinting of neutralizing antibody responses

The impact of the infecting SARS-CoV-2 variant of concern (VOC) and the vaccination status was determined on the magnitude, breadth, and durability of the neutralizing antibody (nAb) profile in a longitudinal multicentre cohort study. 173 vaccinated and 56 non-vaccinated individuals were enrolled after SARS-CoV-2 Alpha, Delta, or Omicron infection and visited four times within 6 months and nAbs were measured for D614G, Alpha, Delta, BA.1, BA.2, BA.5, BQ.1.1, XBB.1.5 and JN.1. Magnitude-breadth-analysis showed enhanced neutralization capacity in vaccinated individuals against multiple VOCs. Longitudinal analysis revealed sustained neutralization magnitude-breadth after antigenically distant Delta or Omicron breakthrough infection (BTI), with triple-vaccinated individuals showing significantly elevated titres and improved breadth. Antigenic mapping and antibody landscaping revealed initial boosting of vaccine-induced WT-specific responses after BTI, a shift in neutralization towards infecting VOCs at peak responses and an immune imprinted bias towards dominating WT immunity in the long-term. Despite that bias, machine-learning models confirmed a sustained shift of the immune-profiles following BTI. In summary, our longitudinal analysis revealed delayed and short lived nAb shifts towards the infecting VOC, but an immune imprinted bias towards long-term vaccine induced immunity after BTI. This work was funded by the Bavarian State Ministry of Science and the Arts for the CoVaKo study and the ForCovid project. The funders had no influence on the study design, data analysis or data interpretation.

Bispecific antibody and chimeric antigen receptor (CAR) modified T-cell in the treatment of multiple myeloma: where do we stand today?

Bispecific antibody and chimeric antigen receptor (CAR) modified T-cell in the treatment of multiple myeloma: where do we stand today?

Electrochemical Determination of Type-Specific Antigens (TSA) Associated with Orientia tsutsugamushi (Scrub Typhus) by a Graphene Quantum Dot (GQD)-Modified Screen-Printed Paper Electrode (SPPE)

Graphene quantum dots (GQDs) were used for surface modification of a screen-printed paper electrode (SPPE) for the development of a mobile phone-integrated immunosensor for the detection of scrub typhus. GQDs were synthesized from a 1.8% starch solution via a hydrothermal method and characterized by ultraviolet–visible (UV–Vis) spectroscopy, fluorescence, Fourier transform infrared spectroscopy and dynamic light scattering. Furthermore, anti-56 kDa type specific antigen (TSA) antibodies were used for immobilization on the GQD-modified SPPE working electrode using EDC/NHS (N-ethyl-N′-(3-(dimethylamino)propyl)carbodiimide/N-hydroxysuccinimide) (1:1) chemistry. The TSA antigen was used at different concentrations to interact with specific antibodies, and the response was recorded via cyclic voltammetry, differential pulse voltammetry and electrochemical impedance spectroscopy using potassium ferricyanide K4[Fe(CN)6]− as a redox indicator. The developed immunosensor showed an excellent sensitivity of 17.40 µA cm−2 ng−1 and a limit of detection of 0.399 ng µL−1. The developed immunohybrid sensor is a novel mobile phone-integrated, highly specific and stable platform for Orientia tsutsugamushi.

Abstract IA018: Determinants of B cell fate and function in cancer

Abstract Effector B cell responses in solid malignancies are associated with favorable response to immunotherapy. B cells can amplify anti-tumor immune responses via antibody production, antigen presentation, and pro-inflammatory cytokine release; yet B cells in cancer patients and tumor-bearing mice often fail to support these functions. We have evaluated the contribution of either systemic inflammatory cues or antigenic quality to B cell differentiation and function in cancer. First, we identify dysregulated transcriptional programs activated in pancreatic cancer-associated B cells that promote differentiation of naïve into immunosuppressive B cells and inhibit differentiation of anti-tumor plasma cells. Second, we find that systemic exposure to STING agonists potentiates expansion of immunosuppressive regulatory human and mouse IL35+ B lymphocytes. Finally, using a system where a B cell neoantigen is either soluble or tethered to the surface of cancer cells, we demonstrate that membrane-tethered antigen is sufficient to elicit activation of anti-tumor immunity and reduce tumor growth in a NK cell-dependent manner. Thus, inflammation and quality of antigen impact basic mechanisms governing B cell differentiation and the resulting immune response to solid malignancy with implications for vaccine engineering. Citation Format: Yuliya Pylayeva-Gupta. Determinants of B cell fate and function in cancer [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Tumor-body Interactions: The Roles of Micro- and Macroenvironment in Cancer; 2024 Nov 17-20; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(22_Suppl):Abstract nr IA018.

Abstract 4138738: Clinical Evidence of Immune Response to Transplanted Allogeneic iPS Cell-Derived Cardiomyocytes

Background&Purpose: The clinical application of cell transplantation therapy utilizing induced pluripotent stem cells (iPS cells) for heart failure is progressing, with the primary strategy being the use of pre-prepared allogeneic iPS cells. The immune response to these transplanted cells is crucial and may affect therapeutic efficacy, necessitating the use of immunosuppressive drugs. However, detailed clinical reports on immune responses are sparse. This study aims to analyze the immune response to transplanted cells in clinical iPS cell-derived cardiomyocyte (iPSC-CM) transplants and examine the correlation between immune response and therapeutic efficacy. Methods: In the "Phase 1 multicenter clinical trial of transplantation of iPSC-CMs for ischemic cardiomyopathy" (https://jrct.niph.go.jp/en-latest-detail/jRCT2053190081), conducted as the First-in-Human trial, the immune response to transplanted cells was analyzed in four cases at our hospital. Comprehensive analysis of anti-human leukocyte antigen (HLA) antibodies in serum and single-cell RNA sequencing in peripheral blood mononuclear cells was performed to investigate their relationship with therapeutic effects on cardiac function. Results: Patients received immunosuppressive drugs (tacrolimus, mycophenolate mofetil, and steroids) for 3 months post-transplantation, followed by a 1-year follow-up. In all cases, an increase in transplant cell HLA-specific antibodies was observed after discontinuing immunosuppressive drugs (Figure 1 and 2). Single-cell analysis revealed a decrease in immunocompetent cells in peripheral blood during immunosuppressive therapy. Cardiac function analysis showed improvements in all cases except Case 2 (Figure 3), where pre-existing anti-HLA-DQ antibodies were present before transplantation. Conclusions: No immune response to the transplanted cells was observed during immunosuppressive therapy. In a case with limited therapeutic response, pre-existing antibodies to transplanted cells were detected, potentially impacting the therapeutic outcome.

The Role of B Cells in Solid Tumors

A surge of recent studies have identified B cells as pivotal contributors to shaping the tumor microenvironment (TME) within solid tumors. B cells can both directly and indirectly antagonize tumor growth via antibody production, antigen presentation, and cytokine secretion, potentially through the formation of tertiary lymphoid structures. However, certain B cell states have demonstrated the ability to promote tumor growth via immunoregulatory mechanisms such as the production of immunosuppressive cytokines and the expression of immune checkpoints, both of which dampen T cell–dependent antitumor responses. Here, we discuss the dichotomy of B cell function in solid tumors, underscoring both the pro- and antitumor roles that B cells play in the TME. Furthermore, we summarize ongoing efforts to reprogram protumorigenic B cells and/or to promote the activity and abundance of effector B cells as potential immunotherapy approaches in solid tumors.

Dengue Encephalopathy, its Presentations and Outcome, A Study on 200 Dengue Encephalopathy Patients in Tertiary Level Hospitals in Bangladesh

Background: Dengue encephalopathy represents a severe neurological complication of dengue infection, yet comprehensive data from Bangladesh remains limited despite the country's high disease burden. Objective: To analyze the clinical characteristics, laboratory parameters, neuroimaging findings, and outcomes of dengue encephalopathy cases in Bangladesh, and to identify prognostic factors for adverse outcomes. Methods: This prospective observational study examined 200 cases of dengue encephalopathy across five tertiary care centers in Bangladesh from January 2020 to December 2023. Diagnosis was confirmed through NS1 antigen and/or dengue-specific antibody testing. Clinical features, laboratory parameters, neuroimaging findings, and outcomes were analyzed using standardized protocols. Results: The cohort (59% male; mean age 34.6±15.3 years) showed neurological manifestations at a median of 5.2 days post-fever onset. Common presentations included altered consciousness (100%), seizures (43%), and focal neurological deficits (27%). Significant neuroimaging findings were observed in 56% of cases, predominantly cerebral edema (28.5%) and meningeal enhancement (17%). ICU admission was required in 43% of cases. The overall mortality rate was 12%, while 71% achieved complete neurological recovery. Multivariate analysis identified GCS <8 at admission (OR: 3.8, 95% CI: 2.1-6.9), presence of shock (OR: 2.9, 95% CI: 1.8-4.7), and platelet count <20,000/µL (OR: 2.4, 95% CI: 1.5-3.8) as independent predictors of poor outcomes. Conclusion: Dengue encephalopathy in Bangladesh presents with distinct clinical patterns and carries significant mortality risk. Early recognition of prognostic factors, standardized management protocols, and adequate critical care support are crucial for improving outcomes. The findings provide a framework for managing similar cases in endemic regions and highlight areas for future research.

Viral Hepatitis B and C Prevalence and Related Risk Factors Among Prisons in Duhok City, Kurdistan Region, Iraq.

Background Infection with hepatitis B virus (HBV) and hepatitis C virus (HCV) are major public health problems worldwide. Public health services are still confronted with the problem of HBV and HCV infections, which calls for targeted preventative measures, especially for critical groups such as prisoners. Therefore, the study aims to measure the prevalence of HBV and HCV infections and to investigate their risk factors among prisoners in Duhok City, Kurdistan, Iraq. Methods A cross-sectional study was performed at the two main prisons inside Duhok city. There were a total of 1,013 inmates: at the Zerka jail, there were 945 male inmates, and at the Etiti jail, there were 50 adult females and 18 adolescent male inmates. Data collection was performed by a direct interview using a structured questionnaire on sociodemographic characteristics and risk factors. Serum samples were tested for HBV surface antigen (HBsAg) and HCV antibody (HCV-Ab) by enzyme-linked immunosorbent assay. Results The mean age of the participants was 35.9 years. The prevalence of HBV and HCV infections was 1.28% and 0.09%, respectively. HBV infection was significantly associated with occupation and marital status. The main risk factors were previous history of surgery and tooth extraction. Conclusions In conclusion, the prevalence of HBV was low while that of HCV was very low. It is usually recommended to take steps to screen for and treat HBV and HCV in patients.

MBS314, a G Protein-Coupled Receptor Family C Group 5 Member D (GPRC5D) x B-Cell Maturation Antigen (BCMA) x CD3 Trispecific Antibody, in Relapsed and/or Refractory Multiple Myeloma (RRMM): Preliminary Results from a Phase Ⅰ, First-in-Human, Open-Label, Dose Escalation Study

MBS314, a G Protein-Coupled Receptor Family C Group 5 Member D (GPRC5D) x B-Cell Maturation Antigen (BCMA) x CD3 Trispecific Antibody, in Relapsed and/or Refractory Multiple Myeloma (RRMM): Preliminary Results from a Phase Ⅰ, First-in-Human, Open-Label, Dose Escalation Study

A comprehensive review of immune checkpoint inhibitor-related diabetes mellitus: incidence, clinical features, management, and prognosis.

Immune checkpoint inhibitor-related diabetes mellitus (ICI-DM) is a rare complication that medical oncologists seldom encounter in routine practice. The sporadic nature and intrinsic complexity of ICI-DM make it challenging to analyze comprehensively in experimental settings. In this review, we examine phase 3 clinical trials on ICIs and published case reports of ICI-DM, aiming to summarize its incidence, clinical features, management, and prognosis. Phase 3 clinical trials reveal that the incidence of ICI-DM is higher with combination therapies, such as anti-PD-1 and anti-CTLA-4 or anti-PD-L1, compared to anti-PD-1 monotherapy. ICI-DM typically presents as severe hyperglycemia with a fulminant onset and is often associated with diabetic ketoacidosis, accompanied by unexpectedly low HbA1c and C-peptide levels. ICI-DM shares similarities with classic type 1 diabetes, particularly in terms of autoimmunity and genetic predisposition. This includes a high prevalence of islet autoantibodies and susceptibility to certain HLA haplotypes, often with concurrent endocrine gland dysfunction. This suggests that genetic susceptibility and exposure to ICIs may both be necessary for triggering islet autoimmunity and inducing ICI-DM. Notably, patients with positive islet autoantibodies, such as glutamic acid decarboxylase antibody and islet-associated antigen 2 antibody, tend to experience rapid onset of ICI-DM after ICI exposure. Although patients with ICI-DM generally show a high objective response rate to immunotherapy, a significant proportion also face the need to permanently discontinued treatment. Further research is urgently needed to determine whether permanent discontinuation of immunotherapy is necessary and whether this discontinuation negatively impacts overall survival.

Epidemiology, Pathogenesis, and Vaccine Development of Acne

Acne is a widespread and chronic inflammatory disease of the pilosebaceous glands affecting millions of people worldwide, particularly among adolescents. The current treatment method is mainly oral and smear medication, combined with a variety of physical and chemical therapy used as adjuvant therapy, alternative therapy or sequelae treatment. However, due to antibiotic resistance and bacteria evolve over time, need a vaccine as a new alternative treatment, in recent years, with the rapid development of molecular biology and immunology, based on specific antigen antibody technology acne vaccine has made significant progress, but there is still no successful development of acne vaccine. This paper analyzes the main four pathogenesis of acne and the current treatment, including oral and daub anti-inflammatory drugs and antibacterial drugs, supplemented by physical and chemical therapy, focus on the development of acne vaccine, present situation, challenges and future trend, hope to further promote the research and development of acne vaccine provide certain theoretical basis and reference value, and provide new ideas and methods for the prevention and treatment of acne. And acne pathogenesis complex and cannot determine the vaccine clinical trial effect these two problems are not solved, pathogenic mechanism involves multiple complex factors, a single vaccine may not have enough protective effect, difficult to completely prevent or cure acne, therefore, the next step need to consider targeting multiple pathogens and virulence factors combination of multivalent vaccine, and need for long-term clinical trials and observation.

Prevalence of Co-infection of Hepatitis B Virus and Hepatitis C Virus among Human Immunodeficiency Virus Patients on Antiretroviral Therapy at A Tertiary Care Centre, Eluru, Andhra Pradesh, India

HIV, HBV, and HCV can form a pretty challenging trio when they coexist. Managing co-infection is crucial for the overall health of the individual, especially considering the potential impact on the liver. Regular monitoring and appropriate medical care can make a significant difference in the outcome for co-infected patients. To ascertain the seroprevalence of HBV and HCV in individuals with HIV attending the Anti-Retroviral Therapy (ART) center affiliated with a tertiary care hospital in Eluru, Andhra Pradesh. Over an 8-month duration, blood samples were obtained from all the individuals visiting the ART Centre. These samples underwent screening for surface antigen of HBV (HBsAg) and antibodies against HCV (anti HCV) by using rapid card tests. Positive samples were subsequently validated through ELISA testing. Baseline CD4 counts, CD4 count after receiving ART were assessed in individuals with HIV alone and those with coinfection of HBV. HIV viral load tests were conducted in individuals with HIV infection and those with coinfection of HBV, assessing their response to ART. Statistical analysis was applied to examine the obtained results. Among the 4382 participants, the seroprevalence of HBV & HCV was 0.02%. The baseline CD4 values averaged 310 for HIV mono-infection cases and 223 for HIV/HBV co-infection cases, indicating a statistically significant distinction with a P value of 0.03. Likewise, the mean values of the CD4 counts after taking ART in individuals with HIV alone and those with coinfection of HBV were 675 and 599, respectively, with a statistically significant P value of 0.05. The study revealed a substantial enhancement in the effectiveness of ART, as indicated by HIV-1 viral load values, in both mono-infection and co-infection cases. Considering the similarity in the main transmission routes of HIV, HBV, and HCV, it is anticipated that hepatotropic viruses would be present in individuals with HIV infection.

Prevalence of Antineutrophil cytoplasmic Antibodies in Systemic Lupus Erythematosus and its relevance with Clinical manifestations

Background: Role of anti-neutrophil cytoplasmic antibodies (ANCA) in pathogenesis of systemic lupus erythematous (SLE) and its association with clinical manifestations is not completely understood. Prevalence data of ANCA in SLE patients of Indian population is limited. Aims and Objectives: The aim of the present study is to measure the prevalence of ANCAs in SLE patients and study its association with clinical manifestations of SLE. Material and Methods: Total 92 patients of SLE cases were included in this prospective observational study. Demographic, clinical and laboratory data was collected in all patients. Serum levels of myeloperoxidase (MPO)-ANCA, proteinase 3 (PR3)-ANCA, antinuclear antibody (ANA), anti-dsDNA antibody and extractable nuclear antigen (ENA) antibodies were measured by enzyme immune assay methods. Serum Complement C3 and C4 estimation was done by nephelometer. Unpaired t test was used to find the significance difference in mean value between ANCA positive and ANCA negative group. Chi-square test was used to compare categorical data of two groups. Results: Nineteen cases (20.65%) showed ANCA positivity. Ten cases were positive for PR3-ANCA and seven cases were positive for MPO-ANCA. Two cases were detected with dual MPO and PR3-ANCA. Nephritis was significantly more common in ANCA positive SLE patients. Rest all of clinical manifestations, anti-dsDNA antibody positivity, ENAs antibodies positivity and reduction in complement level did not show any significant correlation with presence of ANCA antibody. Conclusion: In contrast to results of earlier studies, PR3-ANCA was more prevalent in our study population. Renal system involvement was significantly high in ANCA positive SLE patients as compared to ANCA negative patients.

Molecular recognition characteristics of co-assembled peptides on atomically flat graphite surfaces

Molecular recognition, involving the binding of two or more molecules, is widely found in multiple disciplines. It plays a crucial role in driving specific molecular functionalization or biological activities such as antigen–antibody interactions. Recently, the molecular recognition of single peptides self-assembly at interfaces has been widely investigated since their broad applications in biosensors and bioelectronics. However, the recognition characteristics of peptide-peptide co-assembly on solids have not been investigated yet, which provides a basis for potential multi-probes biosensing or structure-intermingled functionalized bioelectronic applications. Here, we explored the molecular recognition characteristics of co-assembled peptides on two-dimensional (2D) layered nanomaterials, specifically graphite. Our findings showed distinct surface characteristics of peptide co-assembly in comparison to the independent peptide self-assembly. Peptide co-assembly exhibited the nucleation and growth heterogeneities with reduced nucleation and growth rates, dominated by a diffusion-limited step as confirmed via carrying out the sequential assembly experiments. Moreover, molecular dynamics simulation reveals a slowdown binding process of co-assembled peptides to graphite. Furthermore, the misattachment of one peptide to arrays of another type of peptide with distinct structural ordering orientations severely postponed peptide elongation. Therefore, our work provides valuable insight into the fundamental surface characteristics of two co-assembled peptides as they specifically recognize graphite surface via undergoing continuous surface behaviors from binding to diffusion until final ordering process. The formation of co-assembled peptide patterns on 2D layered nanomaterials incorporates multiple functions, enabling to provide potential applications in intermingled peptide-based biosensing or bioelectronic nanodevices.

Evaluation of a multiplexed immunoassay for assessing long-term humoral immunity Orthopoxviruses

BackgroundThe 2022 Monkeypox virus (MPXV) global outbreak boosted development of multiple serological assays to aid understanding of Mpox immunology. ObjectivesThe study aimed to assess a multiplexed solid-phase electrochemiluminescence immunoassay (Meso Scale Discovery (MSD)) for simultaneous detection of antibodies against MPXV, including A35, E8 and M1 antigens, along with corresponding Vaccina Virus (VACV) homologues and demonstrate its accuracy in assessing antibody titres post-vaccination and infection. MethodsAssay performance was assessed for simultaneous detection of antibodies against MPXV and corresponding VACV antigens. Sensitivity and specificity were evaluated with paediatric negatives (n = 215), pre- and post-IMVANEX vaccinated (n = 80), and MPXV (Clade IIb, n = 39) infected serum samples. ResultsThe assay demonstrated high specificity (75.68 % (CI: 69.01–81.29) - 95.98 % (CI:92.54–97.87)) and sensitivity (62.11 % (CI:52.06–71.21) - 98.59 % (CI:92.44 %–99.93 %)) depending on the Orthopoxvirus antigen. Preferential binding was observed between MPXV-infected individuals and MPXV antigens, while vaccinated individuals exhibited increased binding to VACV antigens. These results highlight differential binding patterns between antigen homologues in related viruses. ConclusionOverall, this assay demonstrates high sensitivities in detecting antibodies for multiple relevant MPXV and VACV antigens post-infection and post-vaccination, indicating its utility in understanding immune responses to Orthopoxviruses in current and future outbreaks and evaluating the immunogenicity of new-generation Mpox-specific vaccinations.