Search Results (687)

Hepatitis C virus (HCV) still lacks a licensed vaccine. The envelope glycoprotein E2 is a key neutralizing target, but its dense N-glycan shield can hinder epitope exposure. In this study, we revisit E2 glycan editing and examine whether single-site deletion preserves antigen integrity while improving immune responses in mice under a DNA immunization setting. Using a secreted E2 ectodomain (sE2384–661), we generated five N to D mutants at conserved sites (N1, N2, N4, N6, and N11) and evaluated them in a unified DNA immunization model with identical CpG content and delivery conditions across groups. The N2 mutant (N423, sE2-N2) maintained expression, secretion, and ER localization; furthermore, in mice, it was associated with higher anti-E2 titers and greater inhibition of H77 (genotype 1a) HCVcc at the tested dilutions, with limited activity against Con1 (1b). Cellular analyses showed increased IFN-γ ELISPOT counts and higher frequencies of granzyme B⁺/perforin⁺ CD8⁺ T cells after N2 immunization, while IL-4 remained low. Functionally, N2 elicited stronger specific lysis of CT26-sE2 targets in vitro and slowed CT26-sE2 tumor growth in vivo. In HCV-infected ICR^4R+ mice, therapeutic vaccination with sE2-N2 reduced blood HCV RNA and hepatic readouts compared with sE2. A monoclonal antibody isolated from sE2-N2-immunized mice (1C1) neutralized HCVcc in vitro and, after passive transfer, lowered viremia and liver signals in infected mice. Collectively, these findings indicate that selective removal of the N2 glycan preserves antigen properties and is associated with improved humoral and cellular immunity and measurable in vivo activity, supporting targeted glycan editing as a practical strategy to refine E2-based HCV vaccines. Full article

Colorectal cancer (CRC) remains a major cause of cancer-related deaths in advanced disease, and activating KRAS/NRAS mutations limit the use of anti-EGFR antibodies to RAS–wild-type tumors. The cellular prion protein (PrP^C) has been linked to aggressive and chemoresistant CRC, but its extracellular partners and functional relevance in KRAS-mutant disease are not fully defined. Here, we examined extracellular PrP^C complexes and PrP^C-associated signaling in CRC cell lines and xenografts using a neutralizing PrP^C monoclonal antibody. Across a CRC panel that included SNU-C5/WT and its 5-fluorouracil- and oxaliplatin-resistant derivatives, HT-29 (KRAS–wild-type), and HCT-8 and LoVo (KRAS-mutant), co-immunoprecipitation showed that PrP^C forms complexes with the 37/67 kDa laminin receptor (RPSA), with PrP^C–RPSA association particularly increased in KRAS-mutant HCT-8 and LoVo cells. PrP^C protein levels were higher in KRAS-mutant HCT-8, SW620, and SNU-407 cells than in HT-29, and PrP^C neutralization reduced viability in all four lines. Accordingly, we assessed upstream RAS activity and found that active RAS (RAS-GTP) was higher in KRAS-mutant cells than in HT-29, and PrP^C treatment was associated with reduced RAS-GTP levels. In the same KRAS-mutant setting, basal AKT phosphorylation exceeded that in HT-29, and PrP^C treatment lowered AKT phosphorylation without changing total AKT. Moreover, PrP^C treatment was associated with reduced ERK1/2 phosphorylation in KRAS-mutant cells, suggesting attenuation of downstream RAS pathway output. These signaling changes coincided with a decrease in the S-phase fraction and an increase in G1. In an HCT-8 (KRAS G13D) xenograft model, PrP^C monotherapy inhibited tumor growth in a dose-dependent manner, and 5-fluorouracil (5-FU) monotherapy produced an intermediate effect. The combination of PrP^C (10 mg/kg) and 5-FU (20 mg/kg) yielded the greatest tumor growth inhibition among the tested regimens. Consistent with this enhanced tumor control, immunofluorescence of xenograft tissues showed that PrP^C, particularly with 5-FU, reduced intratumoral PrP^C and PCNA and decreased CD31-positive microvessels and α-SMA–positive vessel structures. Taken together, these findings suggest that extracellular PrP^C supports RAS–AKT signaling, proliferation, and tumor-associated angiogenesis in KRAS-mutant colorectal cancer, and that PrP^C neutralization additively enhances 5-fluorouracil activity in KRAS-mutant models. The data provide a preclinical basis for evaluating PrP^C antibodies in combination with fluoropyrimidine-based regimens in patients with KRAS-mutant CRC. Full article

Background/Objectives: Vedolizumab (VDZ), a monoclonal antibody targeting α4β7 integrin, is used in Crohn’s disease (CD) management, yet patients’ responses vary, underscoring the need for pharmacogenomic (PGx) markers. This study aimed to identify PGx pathways associated with suboptimal VDZ response using a rare-variant analytical framework. Methods: DNA from 63 CD patients treated with VDZ as first-line advanced therapy underwent whole-exome sequencing. Clinical response at week 14 classified patients as optimal responders (ORs) or suboptimal responders (SRs). Sequencing data were processed using GATK Best Practices, annotated with variant effect predictors, and filtered for rare damaging variants (damaging missense and high-confidence loss-of-function; minor allele frequency < 0.05). Variants were mapped to genes specific for SRs and ORs, and analyzed for pathway enrichment using the Reactome database. Rare-variant burden and composition differences were assessed with Fisher’s exact test and SKAT-O gene-set association analysis. Results: Suboptimal VDZ response was associated with pathways related to membrane transport (ABC-family proteins, ion channels), L1–ankyrin interactions, and bile acid recycling, while optimal response was associated with pathways involving MET signaling. SKAT-O identified lipid metabolism-related pathways as significantly different—SRs harbored variants in pro-inflammatory lipid signaling and immune cell trafficking genes (e.g., PIK3CG, CYP4F2, PLA2R1), whereas ORs carried variants in fatty acid oxidation and detoxification genes (e.g., ACADM, CYP1A1, ALDH3A2, DECR1, MMUT). Conclusions: This study underscores the potential of exome-based rare-variant analysis to stratify CD patients and guide precision medicine approaches. The identified genes and pathways are potential PGx markers for CD patients treated with VDZ. Full article

Cutaneous T-cell lymphoma (CTCL) is a heterogeneous malignancy characterized by the proliferation of skin-homing CD4⁺ T cells and profound immune dysregulation within the tumor microenvironment (TME). This review synthesizes evidence on chemokine–receptor networks that govern malignant T-cell trafficking among blood, skin, and lymph nodes, the formation of immunosuppressive niches, and clinically actionable biomarker candidates. Among the best-supported axes, CCL17/CCL22–CCR4 and CCL27/CCL28–CCR10 mediate skin tropism, CCL19/CCL21–CCR7 contributes to lymph node homing, and CXCL12–CXCR4 supports skin trafficking and is associated with disease progression. In contrast, CCR2/CCR5/CCR6/CCR8-centered circuits and CXCR3/CXCR5 pathways are emerging regulators of myeloid recruitment, regulatory T-cell accumulation, and context-dependent immune activation. Therapeutically, agents targeting chemokine pathways, most notably the CCR4 monoclonal antibody Mogamulizumab, have demonstrated clinical efficacy, while emerging inhibitors of CCR6, CCR5, and CXCR4 offer promising avenues for intervention. We further highlight how recent single-cell and other high-dimensional omics studies refine cell-type–specific chemokine sources and receptor expression, enabling more precise mapping of chemokine-driven intercellular communication programs in CTCL TME remodeling and better prioritization of therapeutic targets and biomarkers. Full article

BST2 has emerged as a multifunctional molecule that bridges antiviral defense, membrane architecture, and tumor immunity. Originally characterized as an interferon-inducible restriction factor that tethers virions to the plasma membrane, BST2 is now recognized as an oncogenic driver and immunoregulatory hub in diverse malignancies. In cancer, BST2 expression is frequently upregulated through promoter hypomethylation and transcriptional activation. Functionally, BST2 promotes proliferation, epithelial–mesenchymal transition, anoikis resistance, and chemoresistance, whereas its loss sensitizes tumor cells to proteotoxic and metabolic stresses. Beyond tumor cells, BST2 modulates the tumor microenvironment by promoting M2 macrophage infiltration, dendritic cell exhaustion, and natural killer (NK)-cell resistance, thereby contributing to immune evasion. Elevated BST2 expression correlates with poor prognosis in glioblastoma, breast, nasopharyngeal, and pancreatic cancers, and it serves as a circulating biomarker within small extracellular vesicles. In conclusion, BST2 is a dual-function molecule that integrates oncogenic signaling and immune regulation, making it an attractive diagnostic and therapeutic target for hematological and solid tumors. Full article

Background: Small-cell lung cancer (SCLC) is an aggressive type of lung cancer, and several factors are currently used to predict poor outcomes, including performance status (PS), extensive-stage disease, male sex, advanced age, and elevated lactate dehydrogenase (LDH) levels. In this study, we aimed to explore the role of Tegs and inflammatory indices, such as CRP and NLR, in predicting response to immunotherapy. Methods: Fifty-one therapy-naïve ES-SCLC patients and ten healthy donors were enrolled. Peripheral blood mononuclear cells (PBMCs) were isolated and stained with fluorochrome-conjugated monoclonal antibodies. Multicolor flow cytometry was performed to determine the levels of CD8⁺ T cells and CD4⁺ Tregs, as well as their correlation with inflammatory indices and clinical outcomes. Results: ES-SCLC patients harbored higher percentages of CD8⁺ Teffs (p = 0.005) and FOXP3⁺ Tregs (p < 0.0001) in circulation before therapy compared with healthy donors. In addition, high levels of CD3⁺CD8⁺ T effectors were associated with longer PFS (p = 0.018) and longer OS (p = 0.012) compared with patients bearing low levels, while Tregs were not found to be predictive. More importantly, a survival benefit was observed in ES-SCLC patients with a low Treg/Teff ratio, as longer OS was observed in those with high percentages of CD8⁺ Teffs and low FOXP3⁺CTLA-4⁺ Tregs (p = 0.014) compared with those bearing low CD8⁺ Teffs and high FOXP3⁺CTLA-4⁺ Tregs. A low Treg/Teff ratio was further associated with low eosinophil levels and a low NLR before treatment initiation. Conclusions: These findings suggest a novel, easily obtainable blood-based signature that may help predict response to ICIs in ES-SCLC patients. Full article

Bispecific antibodies (BsAbs) have emerged as an important new class drugs for the treatment of multiple myeloma (MM) over the last few years. Currently, BsAbs are only licensed for use as monotherapy in patients with relapsed/refractory MM who have had at least three prior lines of treatment and are triple class-exposed (patients who have received an anti-CD38 monoclonal antibody, an immunodulatory drug, and a proteasome inhibitor). However, their use in earlier lines, including in the upfront setting, is being explored in multiple ongoing clinical trials with promising early results. The BsAbs have specific toxicities, including a high rate of low-grade cytokine release syndrome and, less commonly, immune effector cell-associated neurotoxicity syndrome. These immune-related toxicities occur almost exclusively during the initiation phase of the BsAbs. This has led to frequent hospitalization of patients for the duration of the initial step-up dosing phase. Strategies that could facilitate outpatient step-up dosing, such as tocilizumab prophylaxis, will become even more critical if BsAbs move into earlier lines of treatment and are used in larger numbers of patients. Optimizing infection prophylaxis is critical for ensuring the safe delivery of BsAbs as infection is the leading cause of non-relapse mortality in patients being treated with BsAbs. Multiple strategies to minimize the infection risk, including antimicrobial prophylaxis, immunoglobulin replacement, vaccination and reduced dosing frequency, have been evaluated. The clinical data on the efficacy of these supportive measures are described in this review article alongside the available strategies for mitigating and managing CRS and ICANS. Full article

Background: The survival of newly diagnosed multiple myeloma (NDMM) has improved markedly worldwide with the introduction of proteasome inhibitors (PIs), immunomodulatory drugs (IMiDs), and anti-CD38 monoclonal antibodies. However, real-world progress among Chinese patients remains underexplored. This study evaluated 20-year survival trends in patients with NDMM treated in our institute and benchmarked them against outcomes from the Flatiron Health database in the United States. Patients and methods: Consecutive adults diagnosed with NDMM in our institute between 2003 and 2023 were retrospectively analyzed. U.S. patients were identified from the Flatiron Health database using similar inclusion criteria. Clinical characteristics, first-line regimens, and autologous stem cell transplantation (ASCT) rates were summarized. Overall survival (OS) and progression-free survival (PFS) were estimated by Kaplan–Meier methods. Results: Among 1622 Chinese and 12,582 US patients, median age was 57 vs. 68 years. The median PFS and OS of NDMM patients in our institute was 40.1 months and 99.6 months, respectively. Induction therapy in the NICHE cohort changed markedly from primarily chemo-based therapy to combined PIs + IMIDs-based treatment, whereas these treatments were used much earlier in Flatiron. Uptake of new therapies in China increased rapidly after their inclusion in national health insurance. ASCT utilization was higher overall in China (34.9% vs. 22.1%) but remained lower among patients >65 years (6.7% vs. 12.1%). Conclusions: Two decades of real-world data from a major Chinese myeloma center demonstrate substantial improvements in survival and modernization of NDMM treatment, while highlighting persistent disparities amongst older adults. Full article

Background/Objectives: Canine Diffuse Large B-cell Lymphoma (cDLBCL) is characterized by a high prevalence of MHC II DR (DLA-DR) antigen overexpression. Murine anti-pan-DLA-DR monoclonal antibodies (mAbs) B5 and E11 have been previously observed to promote death of cDLBCL cells in vitro and in vivo. Consequently, DLA-DR antigens are considered a prospective target for passive immunotherapy aside from CD20. While infusion of anti-pan MHC II mAbs has demonstrated tumor suppression in cDLBCL xenografted immunodeficient mice, the relative contributions of direct cellular versus immune-mediated mechanisms to this therapeutic effect remain undefined. This study aimed to dissect these potential mechanisms of mAb E11. Methods: Canine lymphoma and leukemia cell lines CLBL1 and CLB70 were incubated with full E11 antibody or its F(ab′)2 and Fab fragments and cell viability was assessed with sub-G1 assay then, NOD-SCID mice were xenotransplanted with 1.5 × 10⁷ canine CLBL1 cells expressing nanoluciferase and were infused either with mAb E11 or its fragments, each at 1 mg/kg body mass, twice weekly for three consecutive weeks. Tumor burden was monitored by assessing body weight, nanoluciferase activity in blood, and by flow cytometric analyses of bone marrow tumor cell content. Time to tumor progression (TTP) was calculated based on weight loss and luminescence measurements. Results: We observed cytotoxic activity of monovalent E11-Fab fragments in vitro and in vivo. The mean TTP for mice treated with irrelevant mouse IgG antibodies was 9.8 ± 4.65 days. In contrast, treatment with E11 Fab fragments resulted in a TTP of 19.1 ± 2.67 days, which was similar to that achieved with the full E11 mAb (19.5 ± 1.73 days) and E11 F(ab′)2 fragments (18.1 ± 2.9 days). Conclusions: Our findings demonstrate a potent antibody cytotoxicity mechanism that operates in vivo and is independent of cell surface MHC II crosslinking or Fc engagement. These data support the promising potential of E11-Fab fragments for further clinical development as a therapeutic agent in canine lymphoma. Full article

Background: Although anti-CD38 monoclonal antibody-based regimens are standard care for newly diagnosed multiple myeloma (NDMM), direct comparative efficacy and comprehensive real-world safety data remain scarce. Methods: We conducted a systematic review and Bayesian network meta-analysis (NMA) of randomized controlled trials (RCTs). Efficacy was assessed using hazard ratios (HRs) for progression-free survival and odds ratios (ORs) for response rates, with treatment rankings evaluated by Surface Under the Cumulative Ranking (SUCRA) values. Separately, adverse event reports for daratumumab, bortezomib, lenalidomide, and dexamethasone (D_VRd) regimens were extracted from the US FDA Adverse Event Reporting System (FAERS) (Q1 2015–Q2 2025). Statistical analyses were performed using R (4.3.3) and STATA (16.0). Results: The NMA included 33 RCTs. For the primary efficacy endpoints, compared to the standard bortezomib, lenalidomide, and dexamethasone (VRd) regimen, both D_VRd (OR = 3.21, 95% CI: 2.46–4.26; HR = 0.48, 95% CI: 0.38–0.63) and isatuximab plus VRd (Isa_VRd) (OR = 1.71, 95% CI: 1.25–2.32; HR = 0.66, 95% CI: 0.51–0.85) regimens demonstrated superior efficacy. Subsequent pharmacovigilance analysis of D_VRd identified 11,714 FAERS reports, yielding 197 significant adverse drug event signals (64 unlabeled). These signals primarily affected elderly males and showed a bimodal distribution pattern. Conclusions: Combination regimens containing anti-CD38 monoclonal antibodies demonstrate superiority in achieving deep remission and survival benefits, with D_VRd and Isa_VRd regimens showing particularly outstanding performance. However, efficacy and safety profiles vary across different combination regimens. Real-world data analysis further indicates that the D_VRd regimen carries several safety risk signals that remain underappreciated and exhibits a bimodal time distribution pattern. These findings provide new evidence to guide clinical decision-making and risk-stratified monitoring. Full article

Connective tissue disease-associated interstitial lung disease (CTD-ILD) comprises a heterogeneous group of immune-mediated pulmonary disorders with significant morbidity and mortality. The pathogenesis involves complex interactions of autoimmunity, chronic inflammation, and fibrosis. B cells play a central role in these processes through antigen presentation, autoantibody production, cytokine secretion, and the formation of ectopic lymphoid tissue within the lung parenchyma. Rituximab (RTX)—a chimeric anti-CD20 monoclonal antibody—depletes B cells and has emerged as a promising therapeutic agent for CTD-ILD. This review comprehensively presents the immunopathogenic mechanisms underlying CTD-ILD, elaborating on the multifaceted mode of action of RTX and summarizing the evolving clinical evidence. Full article

Antibody-based therapeutics targeting tumor surface markers have transformed cancer treatment; however, their efficacy is frequently limited by tumor escape mechanisms such as antigen loss, phenotypic switching, and heterogeneous target expression. Beyond genetic or transcriptional changes, RNA alternative splicing (AS) has emerged as a central post-transcriptional mechanism driving antigenic diversity and immune escape. This review outlines how AS-generated isoforms remodel surface antigen structure and function across key therapeutic targets—including CD/19/CD20/CD22, EGFR/HER2, VEGF, and PD-1/PD-L1—thereby promoting resistance to monoclonal antibodies, antibody–drug conjugates, and immune checkpoint inhibitors. The aberrant activity of splicing regulators disrupts canonical exon selection, leading to altered receptor signaling or the secretion of soluble decoy isoforms that evade immune recognition. Emerging therapeutic strategies aim to counteract these processes through antisense oligonucleotide-mediated splicing correction, pharmacologic modulation of splicing regulators, and isoform-selective antibody or CAR-T designs. Collectively, understanding splicing-driven antigenic plasticity reveals an additional, dynamic layer of resistance regulation and provides a framework for developing RNA-informed precision antibody therapies designed to restore antigen expression, overcome immune escape, and enhance durable clinical responses. Full article

Osteosarcoma (OS) remains the most common primary malignant bone tumor in adolescents, with conventional treatments yielding only modest improvements in long-term survival. Immunotherapy has emerged as a promising strategy to overcome these limitations. B7-H3 (CD276) stands apart from other potential targets due to its high expression in tumors cells, as well as its strong association with tumor aggressiveness and poor prognosis. This review provides a comprehensive overview of B7-H3, covering its molecular structure, regulatory mechanisms, biological functions, and expression patterns in tumor tissues. We emphasize the dual roles of B7-H3—both immunoregulatory and non-immunoregulatory—in shaping the tumor microenvironment (TME) and facilitating immune evasion. Building on these insights, we summarize current immunotherapeutic strategies targeting B7-H3 in OS, including monoclonal antibodies (mAbs), chimeric antigen receptor T cells (CAR-T), antibody-drug conjugates (ADCs), and bispecific antibodies (bsAbs). These four strategies have their own advantages and deficiencies. Excitingly, rapid advances in nanoparticle-based systems offer promising solutions to overcome the limitations, especially to develop more effective drug delivery systems and to reshape the TME by targeting immune cells. Despite promising progress, significant challenges remain. These include the absence of an identified B7-H3 receptor, the immunosuppressive and heterogeneous nature of the OS TME, and the need for improved targeting specificity and safety. Addressing these challenges through optimization of delivery systems, combination strategies, and the integration of nanotechnology may unlock the full potential of B7-H3-based immunotherapy in the treatment of OS. Full article

Radiopharmaceutical therapy (RPT) offers tumor-selective radiation delivery and represents a promising platform for combination with immune checkpoint inhibitors (ICIs). While prior studies suggest that RPT can stimulate antitumor immunity, synergy with ICIs may depend on radionuclide properties, absorbed dose, and radiation distribution within the tumor microenvironment. This study evaluated how radionuclide selection and dose influence immune stimulation and therapeutic efficacy of GD2-targeted antibody-based RPT combined with ICIs. Dinutuximab, an anti-GD2 monoclonal antibody, was radiolabeled with β⁻-emitters (⁹⁰Y, ¹⁷⁷Lu) or an α-emitter (²²⁵Ac). C57Bl6 mice bearing GD2⁺ tumors received 4 or 15 Gy tumor-absorbed doses, determined by individualized dosimetry, with or without dual ICIs (anti-CTLA-4 and anti-PD-L1). In vivo imaging, ex vivo biodistribution, survival, histological, and gene expression analyses were performed to assess therapeutic and immunological outcomes. All radiolabeled constructs demonstrated preferential uptake in GD2⁺ tumors. Combination therapy improved survival in a radionuclide- and dose-dependent manner, with the greatest benefit in the ²²⁵Ac + ICI group at 15 Gy. Treatment activated type I interferon signaling and increased MHC-I and PD-L1 expression. Notably, ⁹⁰Y reduced regulatory T cells, enhancing CD8⁺/Treg ratios, while ²²⁵Ac induced robust interferon-driven activation. Radionuclide selection and absorbed dose critically shape immune and therapeutic outcomes of antibody-based RPT combined with ICIs, underscoring the importance of delivery mechanism and dose optimization in combination therapy strategies. Full article