Antibodies最新文献

{"title":"Dynamics of 1,3-β-D-Glucan in Invasive Candidiasis: A Narrative Review of Microbiological Aspects and Diagnostic Implications.","authors":"Maddalena Calvo, Marta Caccamo, Dalila Maria Cammarata, Laura Trovato","doi":"10.3390/antib15020028","DOIUrl":"https://doi.org/10.3390/antib15020028","url":null,"abstract":"<p><p>Invasive candidiasis (IC) remains a significant cause of morbidity and mortality among critically ill, hematologic, and neonatal patients worldwide. Rapid and accurate diagnosis is essential to guide timely antifungal therapy and improve outcomes. Among available diagnostic tools, 1,3-β-D-glucan (BDG), a polysaccharide component of the fungal cell wall, has emerged as a key biomarker. BDG assays allow for early detection of probable IC, often preceding positive blood cultures, and offer prognostic information based on serial measurements. Species-specific differences in <i>Candida</i> cell wall composition influence BDG release and diagnostic sensitivity. <i>Candida albicans</i> generally correlates with high BDG levels, whereas <i>Nakaseomyces glabrata</i>, <i>Candida parapsilosis</i>, and <i>Candida auris</i> exhibit variable or lower glucan exposure, limiting assay sensitivity. BDG performance is affected by patient-specific factors, such as prior surgery, transfusions, or coexisting bacterial infections, which may lead to false-positive results. Molecular techniques, including PCR-based assays, provide complementary diagnostic accuracy and species identification, and their combination with BDG testing enhances sensitivity up to 90%. Serial BDG monitoring supports risk stratification and treatment response assessment, with persistent elevations predicting worse outcomes. In neonatal and pediatric populations, optimal cut-off values remain under investigation, highlighting the need for integration with clinical and microbiological data. Overall, BDG represents a valuable adjunct in a multimodal diagnostic workflow, providing both diagnostic and prognostic insights in invasive candidiasis management.</p>","PeriodicalId":8188,"journal":{"name":"Antibodies","volume":"15 2","pages":""},"PeriodicalIF":2.7,"publicationDate":"2026-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13113447/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147760368","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Effect of FcRn Binding on Ocular Disposition of Monoclonal Antibodies.","authors":"Sanika Naware, Saurav Kulkarni, Sahil Salvi, Dhvani Patel, Dhaval K Shah","doi":"10.3390/antib15020027","DOIUrl":"https://doi.org/10.3390/antib15020027","url":null,"abstract":"<p><p><b>Background/Objectives</b>: The neonatal Fc receptor (FcRn) plays a crucial role in extending the systemic half-life of monoclonal antibodies (mAbs), but its influence on ocular distribution remains incompletely understood. This study investigated the impact of FcRn on the ocular disposition of mAbs following systemic administration in rabbits. <b>Methods</b>: New Zealand White rabbits received a single intravenous dose (1 mg/kg) of either wild-type trastuzumab (TS-WT) or its FcRn non-binding variant (IHH). Plasma and ocular tissues (retina, iris-ciliary body, vitreous humor, aqueous humor, cornea, conjunctiva, and tears) were collected at terminal time points up to 336 h for TS-WT and 168 h for IHH. Antibody concentrations were quantified using a validated sandwich ELISA. Pharmacokinetic parameters and antibody biodistribution coefficients (ABC) were calculated to assess the FcRn-mediated effects on ocular distribution. <b>Results</b>: TS-WT demonstrated 2-fold higher systemic exposure compared to IHH. The iris-ciliary body exhibited the highest absolute exposure for both antibodies, with TS-WT showing significantly higher accumulation (ABC_0-168h: 14.95% vs. 8.89%). Retinal distribution remained comparable between antibodies (5.96% vs. 5.51%). Both antibodies were detectable in tears, with ABC value of ~4% reported for TS-WT. TS-WT also demonstrated markedly increased distribution in vitreous humor and tear fluid (3.5- and 5.5-fold higher ABC values, respectively) compared to IHH. The cornea (5.76% vs. 5.57%) and conjunctiva (7.71% vs. 7.21%) showed comparable relative distribution between TS-WT and IHH, while aqueous humor showed minimal differences (0.44% vs. 0.52%). <b>Conclusions</b>: This investigation reveals distinct tissue-specific patterns of FcRn-mediated mAb distribution within the eye. FcRn binding significantly enhanced antibody distribution in ocular tissues, such as the iris-ciliary body, and tears, with less pronounced effects on the retina, cornea, conjunctiva and aqueous humor. These findings provide mechanistic insights for optimizing mAb-based therapeutics for ocular disease and understanding the ocular toxicity of mAb-based therapeutics, such as antibody-drug conjugates.</p>","PeriodicalId":8188,"journal":{"name":"Antibodies","volume":"15 2","pages":""},"PeriodicalIF":2.7,"publicationDate":"2026-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13113779/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147760415","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Multi-Attribute Method (MAM), An Advanced LC-MS Approach for Protein A Resin Performance and Lifecycle Evaluation.","authors":"Jingming Zhang, Matthew Larsen, Timothy Blanc, Babita S Parekh, Ming-Ching Hsieh","doi":"10.3390/antib15020026","DOIUrl":"https://doi.org/10.3390/antib15020026","url":null,"abstract":"<p><strong>Background: </strong>Protein A resins are indispensable for monoclonal antibody (mAb) production, yet their condition and performance are traditionally assessed using indirect or qualitative methods. In this study, the multi-attribute method (MAM), previously applied to therapeutic protein characterization, is systematically adapted for the first time as a unified liquid chromatography-mass spectrometry (LC-MS) platform for Protein A resin analysis.</p><p><strong>Method: </strong>Four Cytiva Protein A resins, MabSelect™, MabSelect SuRe™, MabSelect SuRe™ LX, and MabSelect™ PrismA, were evaluated by MAM for resin identity, Protein A ligand integrity, fouling by impurities, and cleaning performance.</p><p><strong>Results: </strong>MAM enables resin-specific peptide fingerprinting and quantitative monitoring of Protein A ligand post-translational modifications (PTMs), including deamidation, isomerization, and fragmentation induced by repeated clean-in-place (CIP) cycles. Comparative analysis of virgin and used resins revealed ligand degradation and fouling despite engineered alkaline stability, with MabSelect™ showing the greatest susceptibility. Importantly, residual monoclonal antibodies (mAbs) and host cell proteins (HCPs) were directly detected and quantified from the resin matrix, providing a molecular-level assessment of resin cleaning effectiveness not achievable with conventional approaches.</p><p><strong>Conclusions: </strong>This work establishes MAM as a novel, sensitive, and comprehensive strategy for Protein A resin lifecycle management, delivering actionable insight for resin selection, cleaning optimization, and downstream process development.</p>","PeriodicalId":8188,"journal":{"name":"Antibodies","volume":"15 2","pages":""},"PeriodicalIF":2.7,"publicationDate":"2026-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13113048/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147760445","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Immunogenetic Architecture of Chronic Lymphocytic Leukemia at Early Stage: Insights from the O-CLL1 Cohort.","authors":"Davide Bagnara, Andrea Nicola Mazzarello, Monica Colombo, Ennio Nano, Niccolò Cardente, Fabiana Ferrero, Nadia Bertola, Vanessa Cossu, Fabio Ghiotto, Adalberto Ibatici, Emanuele Angelucci, Antonino Neri, Massimo Gentile, Fortunato Morabito, Manlio Ferrarini, Giovanna Cutrona, Franco Fais","doi":"10.3390/antib15020025","DOIUrl":"10.3390/antib15020025","url":null,"abstract":"<p><strong>Background/objectives: </strong>The immunoglobulin heavy-chain variable (IGHV) gene repertoire represents a characteristic feature of chronic lymphocytic leukemia (CLL), although its configuration is not well defined at the early disease stages. The IGHV repertoire of a cohort of early CLL patients was analyzed and compared to that of a \"real-world\" reference cohort.</p><p><strong>Methods: </strong>Patients from the O-CLL1 observational protocol, which enrolled only Binet stage A cases within twelve months from diagnosis, were studied. IGHV/IGHJ rearrangements were sequenced and annotated following ERIC recommendations, and stereotyped subsets were assigned using ARResT/AssignSubsets. The repertoire features were compared with the dataset of a real-world cohort of patients with heterogeneous staging (CTR cohort) and with published early-diagnosis series.</p><p><strong>Results: </strong>IGHV and IGHJ gene distributions and HCDR3-length profiles in O-CLL1 closely mirrored those of CTR, indicating that the BcR IG repertoire at diagnosis is already defined rather than being selected during disease progression. Mutated IGHV (M-CLL) predominated, with a frequency of stereotyped BcR IG comparable to that of other early-diagnosis cohorts. However, within this conserved framework, subset #4 was over-represented among M-CLL from O-CLL without an increased overall IGHV4-34 gene usage, suggestive of a selective expansion rather than a recombinational bias. Subset #4 cases retained canonical HCDR3 motifs and showed time-to-first-treatment like other M-CLL, likely reflecting the younger age structure of O-CLL1.</p><p><strong>Conclusions: </strong>Early-diagnosis CLL displays a biased IGHV repertoire with stereotyped configurations characteristic of CLL, including subsets that are rare in the normal B-cell repertoire. These findings support a central role for antigen-driven selection in shaping CLL evolution.</p>","PeriodicalId":8188,"journal":{"name":"Antibodies","volume":"15 2","pages":""},"PeriodicalIF":2.7,"publicationDate":"2026-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13010646/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147503039","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dermatomyositis with Anti-MDA5 Autoantibodies After SARS-CoV-2 mRNA Vaccination Treated with Tofacitinib: Integrating Literature Evidence and a Novel Observation.","authors":"Maurizio Benucci, Elisa Cioffi, Francesca Li Gobbi, Emanuele Antonio Maria Cassarà, Riccardo Terenzi, Edda Russo, Valentina Grossi, Barbara Lari, Maria Infantino, Mariangela Manfredi","doi":"10.3390/antib15020024","DOIUrl":"10.3390/antib15020024","url":null,"abstract":"<p><p>COVID-19 mRNA vaccines activate type I interferon pathways and in genetically or immunologically predisposed individuals may trigger autoimmune responses, including autoantibodies against melanoma differentiation-associated protein 5 (MDA5). Although cases of dermatomyositis (DM), particularly anti-MDA5-positive DM, have been increasingly reported after SARS-CoV-2 vaccination, its clinical spectrum and management remain incompletely defined. We conducted a narrative review of the literature on post-vaccination dermatomyositis, focusing on clinical features, autoantibody profiles, therapeutic approaches, and outcomes. The review was enriched by the inclusion of a new case: a 60-year-old woman who developed anti-MDA5-positive dermatomyositis two weeks after receiving her fourth dose of the BNT162b2 (Pfizer/BioNTech) vaccine. She presented predominantly with cutaneous and articular manifestations in the absence of interstitial lung disease. Treatment with oral prednisone, intravenous alprostadil, and the Janus kinase inhibitor tofacitinib resulted in marked clinical improvement. This case, together with the literature review, illustrates both typical and atypical presentations of vaccine-associated anti-MDA5 DM, highlights diagnostic challenges without lung involvement, and suggests JAK inhibition as a potential therapeutic option, contributing to a more comprehensive understanding of post-vaccination dermatomyositis.</p>","PeriodicalId":8188,"journal":{"name":"Antibodies","volume":"15 2","pages":""},"PeriodicalIF":2.7,"publicationDate":"2026-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13010631/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147503066","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of Anti-dsDNA Antibodies in Laboratory Practice: Management of Different Analytical Methods and Correlation with HEp-2 Immunofluorescence Patterns.","authors":"Massimo Papale, Carmela Paolillo, Loredana Iafelice, Tiziana Trivisano, Giuseppe Stefano Netti, Elena Ranieri, Gaetano Corso","doi":"10.3390/antib15020023","DOIUrl":"10.3390/antib15020023","url":null,"abstract":"<p><strong>Background: </strong>Anti-double-stranded DNA (anti-dsDNA) antibodies are a key serological marker for systemic lupus erythematosus (SLE) and are commonly assessed in conjunction with anti-nuclear antibody (ANA) testing by indirect immunofluorescence (IIF) on HEp-2 cells. However, their detection is influenced both by the heterogeneity of the autoimmune response and by the characteristics of the analytical method employed, thereby complicating diagnostic interpretation.</p><p><strong>Methods: </strong>In this retrospective single-center study, 3090 consecutive patients undergoing anti-dsDNA analysis were screened, and 138 positive individuals, with anti-dsDNA levels ≥ 15 IU/mL by fluoroenzyme immunoassay (FEIA), were included in the study. A control group of 29 anti-dsDNA-negative patients was also analyzed. Anti-dsDNA-positive patients were stratified by antibody level (low, mild, high), and the results were correlated with HEp-2 IIF titers and fluorescence patterns. Furthermore, in a subset of 30 positive patients, anti-dsDNA antibodies were evaluated using immunoblotting (IB) and the <i>Crithidia luciliae</i> indirect immunofluorescence test (CLIFT). Statistical analyses assessed associations and concordance among methods.</p><p><strong>Results: </strong>Higher anti-dsDNA levels were generally associated with higher HEp-2 IIF titers. However, a considerable percentage (35%) of patients with positive anti-dsDNA were negative by HEp-2 IIF. Notably, high anti-dsDNA levels were detected in 19% of HEp-2 IIF-negative patients (titer < 1:80), 18% of mildly HEp-2 IIF-positive patients (titer 1:80-1:160), and 25% of HEp-2 IIF-positive patients (titer > 1:320). In the subset of 30 positive patients, FEIA analysis showed high concordance with the immunoblot in both IIF-positive (81%) and -negative (100%) patients, while CLIFT demonstrated lower agreement with both FEIA and IB independently of the IIF.</p><p><strong>Conclusions: </strong>Our findings indicate that anti-dsDNA antibody detection may occur independently of HEp-2 IIF positivity and that FEIA, especially when confirmed by immunoblot, represents a reliable approach for anti-dsDNA assessment. The observed results in this study likely reflect differences in epitope recognition and assay sensitivity among methods, suggesting the use of a multi-step diagnostic strategy in the serological evaluation of SLE.</p>","PeriodicalId":8188,"journal":{"name":"Antibodies","volume":"15 2","pages":""},"PeriodicalIF":2.7,"publicationDate":"2026-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13010703/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147503063","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Developability Evaluation of Single-Domain Antibody-Chelator Conjugates for Diagnostic Radiotracers.","authors":"Philipp D Kaiser, Simon Straß, Sandra Maier, Evgenia Herbold, Bjoern Traenkle, Anne Zeck","doi":"10.3390/antib15020022","DOIUrl":"10.3390/antib15020022","url":null,"abstract":"<p><p><b>Background/Objectives</b>: Developability assessment is a critical step in advancing antibody-based molecules toward clinical application. This evaluation typically begins during clinical candidate selection and continues throughout all modifications of the molecule during development. It is guided by the target product profile, which includes the intended administration route and regimen, formulation parameters, and process conditions encountered during manufacturing, storage, and delivery. While developability testing is well established for conventional therapeutic antibodies, strategies for assessing single-domain antibodies (sdAbs) and their conjugates remain underexplored. Here, we present a strategy to test the developability of sdAbs as a case study for two clinical candidates intended as precursors for the production of diagnostic tracers for clinical imaging. <b>Methods</b>: Assays were developed to evaluate chemical and thermodynamic stability, target binding affinity and capacity, and chelation efficiency (\"chelatability\"). Accelerated stability studies were conducted for both unconjugated sdAbs and their chelator conjugated forms following incubation at two pH conditions, at multiple time points, and after twelve freeze-thaw cycles to simulate process conditions and long-term storage. Analytical assays were applied stepwise in a hierarchical approach to minimize experimental effort and material consumption. Candidates exhibiting critical developability features were selectively addressed by assays with increasing precision. <b>Results</b>: A tailored panel of analytical assays optimized for low molecular weight proteins was established and applied to the two clinical candidates, identifying instability hotspots as well as potential mitigation strategies. Successful engineering of a candidate with an initially critical developability profile was achieved. <b>Conclusions</b>: This study demonstrates the implementation of a structured developability assessment strategy for sdAb conjugates. The approach integrates physicochemical and functional stability evaluations, supporting robust candidate selection, formulation development, and method optimization for this class of molecules.</p>","PeriodicalId":8188,"journal":{"name":"Antibodies","volume":"15 2","pages":""},"PeriodicalIF":2.7,"publicationDate":"2026-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13010638/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147503106","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Prevalence of Viral Hepatitis Antibodies Among Alcoholics in Croatia: A Single Center's Results.","authors":"Maja Vilibić, Klara Barbić, Maja Bogdanić, Snježana Židovec-Lepej, Ana Matošić, Ana Sanković, Dalibor Karlović, Leona Radmanić Matotek, Nataša Kutela, Sergej Nadalin, Ema Borko, Vladimir Savić, Ljubo Barbić, Marija Santini, Hrvojka Janković, Vladimir Stevanović, Tatjana Vilibić-Čavlek","doi":"10.3390/antib15020020","DOIUrl":"10.3390/antib15020020","url":null,"abstract":"<p><strong>Background/objectives: </strong>Viral hepatitis A-E represents a significant public health problem. Data on the prevalence of viral hepatitis markers among alcoholics are inconsistent.</p><p><strong>Methods: </strong>The study included 151 patients treated for alcohol abuse in one Croatian center. The control group consisted of 110 individuals from the general population tested for a routine check-up. The prevalence of viral hepatitis markers was assessed using serology and molecular methods.</p><p><strong>Results: </strong>The prevalence rates of hepatitis markers among patients were as follows: anti-HAV, 15.2%; anti-HBs, 11.9%; anti-HBc/anti-HBs, 2.6%; anti-HCV, 4.0%; and anti-HEV, 14.6%. HCV RNA was detected in one patient (0.6%). Compared with the control group, patients showed significantly higher HCV seroprevalence (4.0 vs. 0%), while the prevalence of other hepatitis markers did not differ significantly between the groups. The anti-HAV prevalence was associated with age (from 0% in patients aged <40 years to 42.9% in patients aged 60+ years), employment status (highest among retired individuals at 46.2%), and age of occasional alcohol consumption (highest seroprevalence of 26.3% in those who reported consumption between 22 and 25 years). The association between anti-HEV and educational level was of borderline significance. Logistic regression showed that older and retired patients and those who consumed alcohol occasionally between 22 and 25 years showed higher odds for HAV seropositivity (OR = 11.454-49.400, OR = 6.857, and OR = 4.464, respectively). Patients with university degrees were at lower risk for HEV seroprevalence (OR = 0.083).</p><p><strong>Conclusions: </strong>Alcoholic patients showed a higher HCV seroprevalence than the general population, while the prevalence of other viral hepatitis markers did not differ between the groups. Further studies on a larger cohort of patients are needed to confirm these findings.</p>","PeriodicalId":8188,"journal":{"name":"Antibodies","volume":"15 2","pages":""},"PeriodicalIF":2.7,"publicationDate":"2026-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13010694/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147503088","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Two Highly Specific Mouse Monoclonal Antibodies to the Putative C-Telopeptide of Human Collagen XIα1, a Cancer Biomarker.","authors":"Marcos García-Ocaña, Lorea Legazpi-Olabide, Sandra Rodríguez-Rodero, Paula Rodríguez-Folgueira, Iván Fernández-Vega, Marcos Ladreda-Mochales, Juan R de Los Toyos, Luis J García-Flórez","doi":"10.3390/antib15020021","DOIUrl":"10.3390/antib15020021","url":null,"abstract":"<p><strong>Background: </strong>Collagen XIα1, encoded by the <i>COL11A1</i> gene, is a minor fibrillar collagen that is overexpressed in various human cancers, in which its presence correlates with tumor aggressiveness and progression.</p><p><strong>Methods: </strong>In this study, we developed two novel mouse monoclonal antibodies (mAbs)-anti-colXIα1 clone 3 and anti-colXIα1 clone 9-that target the putative C-telopeptide of human collagen XIα1. These antibodies target the RRHTEGMQA sequence, a unique nine-amino-acid stretch within the putative C-telopeptide of human collagen XIα1.</p><p><strong>Results: </strong>Corresponding to nearly identical V(D)J gene segments and complementarity-determining regions (CDRs), the antibodies specifically bound the RRHTEGMQA epitope in ELISAs but did not react with the C-propeptide. This specificity was further confirmed with the purified anti-colXIα1 clone 9 mAb, which demonstrated strong reactivity against recombinant proteins containing the RRHTEGMQA sequence in both ELISAs and Western blot assays. This sequence seems to behave as a linear B-cell neoepitope, in which the RRHT motif is crucial for epitope recognition. Otherwise, no immunodetections were observed, either in cultures and lysates from the <i>COL11A1</i>-highly expressing A204 human cell line or on tissue sections from specimens of human pancreatic ductal adenocarcinoma (PDAC), with strong desmoplastic reactions.</p><p><strong>Conclusions: </strong>Given the lack of precise knowledge of the characteristics of the putative C-telopeptide of human collagen XIα1, the presented antibodies could enhance our understanding of the processing of human procollagen XIα1 and contribute to better characterization of the tumor microenvironment of <i>COL11A1</i>-expressing cancers.</p>","PeriodicalId":8188,"journal":{"name":"Antibodies","volume":"15 2","pages":""},"PeriodicalIF":2.7,"publicationDate":"2026-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13010705/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147503057","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Camelid-Derived Nanobodies Targeting Human Epidermal Growth Factor Receptor: Screening, Expression, and Functional Validation.","authors":"Yunfeng Liu, Qiting Huang, Dongna Zhang, Yingjun Wang, Shuaiying Zhao, Jianchuan Wen, Yingying Kong, Jianfeng Xu","doi":"10.3390/antib15020019","DOIUrl":"10.3390/antib15020019","url":null,"abstract":"<p><p><b>Objectives:</b> The epidermal growth factor receptor (EGFR) is a clinically relevant membrane receptor that is frequently overexpressed or dysregulated in multiple types of cancer, making it an important target for antibody-based strategies. Nanobodies, derived from camelid heavy-chain antibodies, possess favorable properties such as small size, high stability, and strong antigen-binding capacity. This study aimed to generate EGFR-specific nanobodies and to systematically characterize their binding properties and initial functional activity. <b>Methodology:</b> Bactrian camels were immunized with a whole-cell antigen prepared from 293F cells transiently transfected to express full-length human EGFR. A high-diversity phage display nanobody library was constructed from peripheral blood lymphocytes. After two rounds of biopanning against EGFR, positive clones were screened and selected. The identified nanobodies were recombinantly expressed in Escherichia coli and purified. Binding specificity, epitope relationships, and kinetic parameters were evaluated using high-performance liquid chromatography (HPLC), bio-layer interferometry (Octet), and flow cytometry. The effect of selected nanobodies on EGF-induced cell proliferation was evaluated using a CCK-8 assay. <b>Results:</b> Two EGFR-specific nanobodies, Nb2H4 and Nb2B6, were successfully isolated. Both nanobodies exhibited specific binding to EGFR and recognized distinct, non-competing epitopes. Kinetic analyses revealed favorable binding affinities, and flow cytometry confirmed their ability to recognize EGFR in its native cellular context. In addition, Nb2H4 significantly suppressed EGF-induced proliferation in an EGFR-overexpression cell model, indicating preliminary functional activity. <b>Conclusions:</b> This study reports on the successful generation and in vitro characterization of EGFR-targeting nanobodies based on the extracellular domain of EGFR. The identified nanobodies provide useful molecular tools for epitope mapping, structural studies, and the further exploration of EGFR-directed antibody engineering strategies.</p>","PeriodicalId":8188,"journal":{"name":"Antibodies","volume":"15 2","pages":""},"PeriodicalIF":2.7,"publicationDate":"2026-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13010625/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147503060","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}