Journal of immunological methods最新文献

{"title":"Quantitative flow cytometry using quantitative streptavidin-protein G-biotin beads (qBeads)","authors":"Maitreyi Bharath ,&nbsp;Anh Le ,&nbsp;Vaishnavi Konda ,&nbsp;Shivika Srivastava ,&nbsp;Mark Beliaev ,&nbsp;Mengbing Chen ,&nbsp;Anand George ,&nbsp;Andy Zhang ,&nbsp;Sophie Tan ,&nbsp;Eben Ginto ,&nbsp;Aaditya Awatiger ,&nbsp;Kushagra Bahuguna ,&nbsp;Vienna Li ,&nbsp;Suditi Kedambadi ,&nbsp;Xiaolin Cao ,&nbsp;Hao Zeng ,&nbsp;Guofei Xiong ,&nbsp;Mihika Prabhu ,&nbsp;Ayana Modi ,&nbsp;Yanlan Wang ,&nbsp;John Wang","doi":"10.1016/j.jim.2025.113883","DOIUrl":"10.1016/j.jim.2025.113883","url":null,"abstract":"<div><div>Quantitative flow cytometry (qFCM) is a powerful approach for the precise measurement of cellular and molecular characteristics, offering significant advantages in biomedical research, clinical diagnostics, and therapeutic applications. However, current qFCM beads, relying on chemical conjugation face several limitations. This study explored the use of streptavidin-coated beads with a defined quantity of Protein G-biotin for quantitative flow cytometry, demonstrating that these quantitative streptavidin-Protein G-biotin beads (qBeads) can be used for qFCM analysis through both direct and indirect methods, enabling the development of standardized assays for a wide range of applications.</div></div>","PeriodicalId":16000,"journal":{"name":"Journal of immunological methods","volume":"542 ","pages":"Article 113883"},"PeriodicalIF":1.6,"publicationDate":"2025-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144190358","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development and validation of dengue virus envelope protein domain III IgG antibody enzyme-linked immunosorbent assay","authors":"Juan Ignacio Marfía ,&nbsp;Ignacio Smith ,&nbsp;Alexandra Marisa Targovnik ,&nbsp;Federico Alejandro Di Lello ,&nbsp;Federico Javier Wolman ,&nbsp;Diego Martín Flichman ,&nbsp;María Victoria Miranda ,&nbsp;Silvina Noemí Valdez","doi":"10.1016/j.jim.2025.113887","DOIUrl":"10.1016/j.jim.2025.113887","url":null,"abstract":"&lt;div&gt;&lt;h3&gt;Introduction&lt;/h3&gt;&lt;div&gt;The global incidence of Dengue virus (DENV) infections has significantly increased in recent decades, becoming a public health emergency of global concern. Diagnostic tools for DENV infection include detection of the virus, viral RNA, or viral antigens, which are usually cumbersome or require sophisticated medical facilities and trained personnel. Serological tests are the most widely used methods to detect dengue infection due to low cost and operational simplicity. The detection of antibodies (IgM and IgG) in the blood of an infected individual is an indirect method of diagnosing DENV and IgG can be used as long-term detection. The aim of this work was to develop and validate an enzyme-linked immunosorbent assay (ELISA) for the detection of anti-DENV IgG antibodies, and to determine its usefulness in the diagnosis and seroepidemiological survey of DENV.&lt;/div&gt;&lt;/div&gt;&lt;div&gt;&lt;h3&gt;Materials and methods&lt;/h3&gt;&lt;div&gt;The production of the antigen was carried out using the tetravalent DENV E protein-based provided by Trebe Biotech. The recombinant baculovirus was obtained using the Bac to Bac® baculovirus expression system. The recombinant tetravalent dengue antigen was expressed in insect larvae, purified by IMAC and identified by SDS-PAGE and western blot analysis. The system used in this work has the advantage of using insect pests as biofactories. Recombinant protein production is high-yield and production times are short. Furthermore, it has no product size limit and is highly flexible to sequence changes or the emergence of new serotypes. An indirect ELISA was developed using purified tetravalent DENV antigen immobilized on polystyrene microplates; human sera samples from individuals with no history of DENV infection (&lt;em&gt;n&lt;/em&gt; = 22) and human sera samples from individuals with clinical history and diagnosed of DENV infection (&lt;em&gt;n&lt;/em&gt; = 23) were then incubated. Immune complexes were revealed with anti-human IgG-Horseradish Peroxidase. Results were calculated as specific absorbance and expressed as standard deviation scores: SDs. In order to establish DENV-IgG seroprevalence, the developed ELISA was applied to analyze samples from blood donor centers from different geographic regions of the country (&lt;em&gt;n&lt;/em&gt; = 504) and normal human sera (&lt;em&gt;n&lt;/em&gt; = 17).&lt;/div&gt;&lt;/div&gt;&lt;div&gt;&lt;h3&gt;Results&lt;/h3&gt;&lt;div&gt;The efficiently produced recombinant dengue antigen was used for the development and validation of a high sensitivity (91.30 %) and specificity (90.91 %) indirect ELISA for the detection of anti-DENV IgG antibodies. The ROC curves demonstrated that this method had high accuracy to distinguish between samples from normal control individuals and patients with DENV (AUC = 0.9901); the cut-off value was established at 2 SDs. In the assessment of seroprevalence levels of anti-DENV antibodies, 33 out of 504 analyzed samples (6.55 %) tested positive using our developed ELISA.&lt;/div&gt;&lt;/div&gt;&lt;div&gt;&lt;h3&gt;Conclusions&lt;/h3&gt;&lt;div&gt;This technique is rap","PeriodicalId":16000,"journal":{"name":"Journal of immunological methods","volume":"542 ","pages":"Article 113887"},"PeriodicalIF":1.6,"publicationDate":"2025-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144187132","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multiplex ACE2-RBD binding inhibition assay: An integrated tool for assessing neutralizing antibodies to SARS-CoV-2 variants and protection against breakthrough infections","authors":"Emma Bloch ,&nbsp;Laura Garcia ,&nbsp;Françoise Donnadieu ,&nbsp;Jason Rosado ,&nbsp;Delphine Planas ,&nbsp;Timothée Bruel ,&nbsp;Laurent Hocqueloux ,&nbsp;Thierry Prazuck ,&nbsp;Olivier Schwartz ,&nbsp;Laura Tondeur ,&nbsp;Laurie Pinaud ,&nbsp;Arnaud Fontanet ,&nbsp;Stéphane Pelleau ,&nbsp;Michael White","doi":"10.1016/j.jim.2025.113886","DOIUrl":"10.1016/j.jim.2025.113886","url":null,"abstract":"<div><div>SARS-CoV-2 remains a significant health threat due to its high infection and mutation rates. The emergence of new variants of concern poses challenges as they can lead to immune escape mutations, potentially reducing the efficacy of vaccines and antibody therapeutics. The receptor binding domain (RBD) of SARS-CoV-2 is particularly noteworthy as it is both the most rapidly evolving domain and the principal target of neutralizing antibodies. As an alternative to time-consuming and expensive neutralization assays, we have developed a bead-based multiplex surrogate virus neutralization test based on ACE2-RBD binding inhibition. We demonstrated how our high-throughput assay allows us to simultaneously assess anti-RBD neutralizing antibodies levels against multiple SARS-CoV-2 variants, providing data that is consistent with the gold-standard live virus neutralization assay. The utility of this assay was demonstrated by applying it to a large French population cohort to demonstrate that hybrid immunity (generated by a combination of vaccination and infection) is associated with protection against infection with the Omicron BA.1 and BA.2 lineages of SARS-COV-2.</div></div>","PeriodicalId":16000,"journal":{"name":"Journal of immunological methods","volume":"541 ","pages":"Article 113886"},"PeriodicalIF":1.6,"publicationDate":"2025-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144168562","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development and performance evaluation of a novel, fully automated, high-throughput GAD65 autoantibody assay on the Phadia platform","authors":"Daniel Filchtinski ,&nbsp;José Kayser ,&nbsp;Virginie Ettner ,&nbsp;Sanja Holz ,&nbsp;Bjarne Kristensen ,&nbsp;Johannes Schulte-Pelkum ,&nbsp;Isabel Wilhelm ,&nbsp;Raimund Fiedler","doi":"10.1016/j.jim.2025.113885","DOIUrl":"10.1016/j.jim.2025.113885","url":null,"abstract":"<div><h3>Objectives</h3><div>In clinics, diabetes is determined by blood glucose levels or by glycosylated hemoglobin (HbA1c). However, to distinguish between Type 1 and Type 2 diabetes (T1D and T2D) for adequate treatment, patients are tested for the presence of Type 1 diabetes-relevant autoantibodies in the second tier.</div><div>Anti-GAD65 autoantibody is one of the main markers for T1D in both pediatric and adult T1D patients. If the anti-GAD65 autoantibody is detectable, the patients have type 1 diabetes and need to be treated with insulin.</div><div>In the clinical routine diagnostics of type 1 diabetes, GAD65-serology is performed using a special assay architecture known as bridging ELISA. Adapting these assays onto automated ELISA systems has shown to be a constant challenge, so they can be hardly applied for high throughput testing in a routine clinical laboratory.</div></div><div><h3>Methods</h3><div>We developed the first fully automated, high-throughput GAD65 autoantibody fluorescence enzyme immunoassay based on the bridging immunoassay format on Phadia instrument platform, termed EliA GAD65 and compared its performance with the bridging ELISA from RSR™ (GADAb ELISA) and the fully automated MAGLUMI® GAD65 chemiluminescence assay (CLIA) from Snibe Diagnostics.</div></div><div><h3>Results</h3><div>When tested for clinical performance, ROC Analysis of EliA GAD65 showed an Area under the curve (AUC) of 0.906 (95 % CI 0.864 to 0.949) compared to the AUC of 0.923 (95 % CI 0.884to 0.963) of GADAb ELISA with no significant difference between the two assays (<em>p</em> = 0.384). When adjusted to a specificity of 96 %, EliA GAD65 showed a sensitivity of 76 % (CI 95 % 66.4 % to 84.0 %) compared to a sensitivity of 74 % (95 % CI 64.6 % to 81.6 %) of GADAb ELISA. When the fully automated MAGLUMI® GAD65 CLIA was compared to GADAb ELISA, it showed a total agreement of 92.9 % (95 % CI 86.6 % to 96.4 %) with less positive samples detected in contrast to the total agreement of 100 % (95 % CI 96.7 % to 100 %) of EliA GAD65 to GADAb ELISA.</div></div><div><h3>Conclusions</h3><div>Fully automated EliA GAD65 assay displays similar clinical characteristics as the well-established bridging GADAb ELISA and a higher agreement with the GADAb ELISA than the automated MAGLUMI® GAD65 CLIA.</div></div>","PeriodicalId":16000,"journal":{"name":"Journal of immunological methods","volume":"542 ","pages":"Article 113885"},"PeriodicalIF":1.6,"publicationDate":"2025-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144187131","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reference intervals for functional lymphocyte proliferation studies using ³H thymidine uptake in adults.","authors":"Rohan Ameratunga, Danny Lim, Hilary Longhurst, James Mehrtens, Euphemia Leung, Klaus Lehnert, Richard Steele, See-Tarn Woon","doi":"10.1016/j.jim.2025.113884","DOIUrl":"https://doi.org/10.1016/j.jim.2025.113884","url":null,"abstract":"","PeriodicalId":16000,"journal":{"name":"Journal of immunological methods","volume":" ","pages":"113884"},"PeriodicalIF":1.6,"publicationDate":"2025-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144181180","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of a one-step diagnostic and differential immunochromatographic method for mpox and chickenpox","authors":"Laiqing Li ,&nbsp;Qiang Jia ,&nbsp;Hongrui Lai ,&nbsp;Guoliang Luo ,&nbsp;Yanhong Lu ,&nbsp;Huankun Liang ,&nbsp;Wenqi Dong ,&nbsp;Cuicui Chen","doi":"10.1016/j.jim.2025.113881","DOIUrl":"10.1016/j.jim.2025.113881","url":null,"abstract":"<div><h3>Objective</h3><div>Mpox and chickenpox are highly contagious diseases with similar clinical symptoms and co-infection, and diagnostic tests are extremely useful in their differentiation. Mpox virus and chickenpox virus are the main causative pathogens of mpox and chickenpox respectively. This study aims to develop a rapid diagnostic immunochromatographic trip for differential diagnosis of mpox and chickenpox viruses.</div></div><div><h3>Methods</h3><div>An immunochromatographic assay (ICA) based on the double-antibody sandwich format was developed. First, the paired monoclonal antibodies (MAbs) were prepared: for mpox, the detecting MAb1 and capture MAb2; for chickenpox, the detecting MAb3 and capture MAb4. These MAbs were against the recombinant antigens (AR/gE) of mpox and chickenpox viruses. Then, the detecting MAbs were conjugated to gold nanoparticles and coated onto the conjugate pads. The capture MAbs were immobilized onto a nitrocellulose membrane at two detection zones to form the Test 1 (T1, to test AR) line and Test 2 (T2, to test gE) line, respectively. Goat anti-mouse IgG antibodies were immobilized onto the nitrocellulose membrane to form the control (C, to verify the effectiveness of the strip) line as the control. Finally, it was assembled into a one-step double T-line colloidal gold immunochromatographic test strip for the differential diagnosis of mpox and chickenpox viruses. The sensitivity, specificity, precision and methodology comparison were evaluated using mpox pseudovirus and clinical samples.</div></div><div><h3>Results</h3><div>A dual-index ICA strips for the simultaneous detection of mpox and chickenpox were successfully prepared. The sensitivity of the dual-index ICA strips to AR antigen was 0.125 ng/mL, to gE antigen was 0.25 ng/mL, with high specificity, precision and reproducibility. The results can be judged within 10–15 min. Methodology comparison study (PCR vs. ICA strips) of 56 clinical samples found there was no statistically significant difference between the ICA strips and PCR method.</div></div><div><h3>Conclusion</h3><div>The dual-index ICA strips had good sensitivity, specificity, simple procedure and rapid detection. This protocol is very suitable for early diagnosis and differentiation of mpox and chickenpox in medical institutions and individuals.</div></div>","PeriodicalId":16000,"journal":{"name":"Journal of immunological methods","volume":"541 ","pages":"Article 113881"},"PeriodicalIF":1.6,"publicationDate":"2025-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144134524","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Validation for soluble C5b-9 detection and comparative analysis of three quantification methods","authors":"Tracie Profaizer ,&nbsp;Abdulrahman Saadalla ,&nbsp;Vijayalakshmi Nandakumar","doi":"10.1016/j.jim.2025.113882","DOIUrl":"10.1016/j.jim.2025.113882","url":null,"abstract":"<div><h3>Background</h3><div>Soluble C5b-9 (sC5b-9) is a biomarker of complement activation, representing the soluble form of the Terminal Complement Complex (TCC), which is released into circulation rather than embedding in the cell membrane. Measurement of sC5b-9 is increasingly utilized for detecting complement activation, particularly in conditions like thrombotic microangiopathy and during complement inhibitor therapy. Accurate detection of sC5b-9 can be useful for guiding therapeutic decisions, especially in patients receiving anti-C5 inhibitors. This study aimed to validate the Quidel sC5b-9 ELISA kit and compare its performance with two other assays, Hycult and SVAR, focusing on assay linearity and therapeutic monitoring.</div></div><div><h3>Methods</h3><div>The analytical performance of the Quidel sC5b-9 ELISA kit was evaluated using 60 split samples over a wide concentration range, in collaboration with a peer laboratory. Precision, sensitivity, linearity, and reference limits were assessed, mainly using artificially activated samples with magnesium chloride and Zymosan, covering a broad range of sC5b-9 concentrations. Four patient samples with complement-mediated diseases were also tested. The correlation between the Quidel, Hycult, and SVAR assays was analyzed with 40 samples, while linear ranges were compared using 11 proportionally diluted samples. Additionally, the impact of anti-C5 inhibitors on sC5b-9 concentrations was evaluated by spiking anti-C5 biosimilar drugs into activated plasma.</div></div><div><h3>Results</h3><div>The Quidel sC5b-9 assay showed accuracy, with an R² of 0.90 and a qualitative concordance of 93.3 %. Very few discrepancies were noted in samples near the reference limit. Both intra- and inter-assay precision were below 20% CV for samples above the Limit of Quantification (LOQ) of 170 ng/mL. Linearity studies defined the reportable range for Quidel's assay as 220–1800 ng/mL. Comparisons among Quidel, SVAR, and Hycult assays revealed strong correlations, with the Hycult kit demonstrating a broader linear range, maintaining linearity even at concentrations 10 times higher than its highest calibrator. All assays showed a significant reduction in sC5b-9 concentrations after the addition of 50 μg/mL of Eculizumab biosimilar, with SVAR and Quidel reaching values close to their lowest calibrators. In contrast, the Hycult assay maintained a wide dynamic range even at 100 μg/mL of anti-C5 inhibitor addition.</div></div><div><h3>Conclusions</h3><div>This study confirms that the Quidel sC5b-9 ELISA kit is a reliable tool for detecting complement activation and inhibition. However, the Hycult assay offers a broader dynamic range which can be an important consideration when assessing assay suitability for for disease monitoring and therapeutic assessments.</div></div>","PeriodicalId":16000,"journal":{"name":"Journal of immunological methods","volume":"541 ","pages":"Article 113882"},"PeriodicalIF":1.6,"publicationDate":"2025-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144138956","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Chlamydia trachomatis pgp3 ELISA","authors":"Filomeno Coelho da Silva ,&nbsp;Gathoni Kamuyu ,&nbsp;Kazutomo Yokoya ,&nbsp;Jessica Edney ,&nbsp;Kate Soldan ,&nbsp;Simon Beddows","doi":"10.1016/j.jim.2025.113879","DOIUrl":"10.1016/j.jim.2025.113879","url":null,"abstract":"<div><div><em>Chlamydia trachomatis</em> (Ct) serology is an important tool to support infection and disease surveillance of the population but there are currently no formal reference reagents and few commercial assays available. Our objective was to develop an internally standardized ELISA capable of estimating antibody levels against the virulence factor antigen, pgp3, that could be used for Ct serosurveillance. Purified trimeric pgp3 antigen was stable and the internal standard, quality controls, intra- and inter-assay repeatability metrics were robust. For example, retesting a panel of serum samples (<em>n</em> = 203) resulted in 12 % and 13 % seropositivity for the initial and repeat tests, respectively (Kappa 0.933, 95 %CI 0.857–1.000). A comparison of serum samples from children who would not be expected to have had exposure to Ct and samples from females with a history of chlamydia infection, though not necessarily antibody positive at the time of sampling, generated excellent specificity (99.4 %) and adequate sensitivity (67.9 %) for surveillance purposes. The pgp3 ELISA reports results in antibody levels (AU/mL) which are amenable to recalibration should an international reference reagent be approved in the future.</div></div>","PeriodicalId":16000,"journal":{"name":"Journal of immunological methods","volume":"541 ","pages":"Article 113879"},"PeriodicalIF":1.6,"publicationDate":"2025-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144072438","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparison of mixed modeling regression methods for the assessment of longitudinal CyTOF® data","authors":"Tyson H. Holmes,&nbsp;Caroline Duault","doi":"10.1016/j.jim.2025.113880","DOIUrl":"10.1016/j.jim.2025.113880","url":null,"abstract":"<div><div>A simulation study was conducted to assess Type I error and statistical power of linear mixed models, generalized linear mixed models, and linear quantile mixed models for the analysis of longitudinal cytometry by time-of-flight data. Findings indicate that, while generalized linear mixed models have superior statistical power, they also suffer from inflated Type I error rates. Linear mixed models can have substantially lower statistical power than the other methods at larger effect sizes. While linear quantile mixed models have slightly lower statistical power at smaller effect sizes, they have intermediate statistical power at larger effect sizes and good Type I error control. Taken altogether, these results generally recommend the use of linear quantile mixed models for longitudinal datasets such as for cytometry by time-of-flight data, although linear mixed models may be slightly more useful at small effect sizes and sample sizes.</div></div>","PeriodicalId":16000,"journal":{"name":"Journal of immunological methods","volume":"541 ","pages":"Article 113880"},"PeriodicalIF":1.6,"publicationDate":"2025-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144068668","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Target tolerance improvement of the immunogenicity assay developed for analysing samples from clinical trials of RGB-14, a proposed biosimilar to Prolia/Xgeva","authors":"Tímea Pap,&nbsp;Nikolett Király,&nbsp;Anna Fekete,&nbsp;János Pál Tóth,&nbsp;Attila Kónya","doi":"10.1016/j.jim.2025.113878","DOIUrl":"10.1016/j.jim.2025.113878","url":null,"abstract":"<div><div>An immunogenicity assay was developed to support the clinical program of RGB-14, a proposed biosimilar to Prolia/Xgeva. The ADA assay was successfully validated following current guidelines and white papers. The validation included an assessment of target (RANKL) interference, and the assay passed the test up to a 30 pg/mL RANKL level. This concentration was anticipated to be the maximum level present in clinical samples. Despite the successful validation, most of the analysed samples from the RGB-14 Phase I clinical trial yielded false-positive results for anti-denosumab antibodies. The investigation concluded that unexpectedly high levels of RANKL were present in the samples and caused interference in the assay. Consequently, the assay was re-developed by adding target-specific reagent, eliminating acid dissociation step and doubling the assay dilution to enhance target tolerance to 10,000 pg/mL RANKL, a requirement for clinical sample testing. The re-developed assay underwent successful validation, and the samples from the clinical trials of RGB-14 were subsequently analysed with the improved assay. The article outlines a strategy for enhancing the target (RANKL) tolerance of the ADA assay. It also underscores the importance of monitoring clinical sample analysis results, even if a validated assay is used for sample testing, as clinical samples may differ from the spiked samples prepared for validation. If unexpected results are obtained, an investigation should be initiated, and the assay should be improved if needed to ensure the reliability of the results.</div></div>","PeriodicalId":16000,"journal":{"name":"Journal of immunological methods","volume":"541 ","pages":"Article 113878"},"PeriodicalIF":1.6,"publicationDate":"2025-05-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144072238","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}