Our investigation uncovers that nanomolar concentrations of salinomycin, monensin, nigericin, and narasin (a group of potassium/ sodium cation carriers) robustly enhance surface expression of CD20 antigen in B-cell-derived tumor cells, including primary malignant cells of chronic lymphocytic leukemia and diffuse large B-cell lymphoma. Experiments in vitro, ex vivo, and animal model reveal a novel approach of combining salinomycin or monensin with therapeutic anti-CD20 monoclonal antibodies or anti-CD20 chimeric antigen receptor T cells, significantly improving non-Hodgkin lymphoma therapy. The results of RNA sequencing, genetic editing, and chemical inhibition delineate the molecular mechanism of CD20 upregulation, at least partially, to the downregulation of MYC, the transcriptional repressor of the MS4A1 gene encoding CD20. Our findings propose the cation carriers as compounds targeting MYC oncogene, which can be combined with anti-CD20 antibodies or adoptive cellular therapies to treat non-Hodgkin lymphoma and mitigate resistance, which frequently depends on the CD20 antigen loss, offering new solutions to improve patient outcomes.

The 4CMenB vaccine licensed against serogroup B Neisseria meningitidis (MenB) contains three recombinant proteins and Outer Membrane Vesicles (OMV) from a New Zealand epidemic strain. The protective response mediated on differentmeningococcal strains has been historically ascribed to one of the four main vaccine antigens fHbp, NHBA, NadA, and PorA nominated as the immunodominant antigen of the OMV component. It is however accepted that the extensive cross-protection observed after vaccination may be attributed to other proteins in the OMV. Here we interrogate the B cell responses elicited in humans to the OMV component after 4CMenB vaccination to elucidate the contribution of additional OMV antigens to meningococcal cross-protection.
Following the isolation of plasmablasts from vaccinees, the OMV-specific human monoclonal antibodies (HumAbs) were recombinantly expressed and characterized for their binding and functional activity on a panel of MenB strains. Their target specificity was assessed through a tailor-made protein array and Western blot.
We found that 18 HumAbs showing bactericidal activity were PorB-specific, 1 was LOS-specific and 4 functional HumAbs remain with unknown targets. We identified three functional classes within the PorB HumAbs, through binding and in silico docking experiments, likely to be elicited from distinct epitopes on PorB and highlighting this antigen as a multi-epitope immunogenic OMV component responsible for distinct cross-protection across multiple MenB strains. Interestingly three of the PorB HumAbs and the LOS-specific HumAb showed bactericidal activity also against gonococcus.
We identified PorB and LOS as antigens on the OMV that may be implicated in the real-world observations of moderate protection against gonorrhea infection after OMV-based vaccinations.
Copyright © 2025 Vezzani, Viviani, Audagnotto, Rossi, Cinelli, Pacchiani, Limongi, Santini, Giusti, Tomei, Torricelli, Faenzi, Sammicheli, Tavarini, Efron, Biolchi, Finco, Delany and Frigimelica.

The human dendritic cell (DC) family has recently been expanded by CD1c+CD14+CD163+ DCs, introduced as DC3s. DC3s are found in tumors and peripheral blood of cancer patients. Here, we report elevated frequencies of CD14+ cDC2s, which restore to normal frequencies after tumor resection, in non-small cell lung cancer patients. These CD14+ cDC2s phenotypically resemble DC3s and exhibit increased PD-L1, MERTK, IL-10, and IDO expression, consistent with inferior T cell activation ability compared with CD14- cDC2s. In melanoma patients undergoing CD1c+ DC vaccinations, increased CD1c+CD14+ DC frequencies correlate with reduced survival. We demonstrate conversion of CD5+/-CD1c+CD14- cDC2s to CD14+ cDC2s by tumor-associated factors, whereas monocytes failed to express CD1c under similar conditions. Targeted proteomics identified IL-6 and M-CSF as dominant drivers, and we show that IL-6R and CSF1R inhibition prevents tumor-induced CD14+ cDC2s. Together, this indicates cDC2s as direct pre-cursors of DC3-like CD1c+CD14+ DCs and provides insights into the importance and modulation of CD14+ DC3s in anti-tumor immune responses.
Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.

We describe a human lung disease caused by autosomal recessive, complete deficiency of the monocyte chemokine receptor C-C motif chemokine receptor 2 (CCR2). Nine children from five independent kindreds have pulmonary alveolar proteinosis (PAP), progressive polycystic lung disease, and recurrent infections, including bacillus Calmette Guérin (BCG) disease. The CCR2 variants are homozygous in six patients and compound heterozygous in three, and all are loss-of-expression and loss-of-function. They abolish CCR2-agonist chemokine C-C motif ligand 2 (CCL-2)-stimulated Ca2+ signaling in and migration of monocytic cells. All patients have high blood CCL-2 levels, providing a diagnostic test for screening children with unexplained lung or mycobacterial disease. Blood myeloid and lymphoid subsets and interferon (IFN)-γ- and granulocyte-macrophage colony-stimulating factor (GM-CSF)-mediated immunity are unaffected. CCR2-deficient monocytes and alveolar macrophage-like cells have normal gene expression profiles and functions. By contrast, alveolar macrophage counts are about half. Human complete CCR2 deficiency is a genetic etiology of PAP, polycystic lung disease, and recurrent infections caused by impaired CCL2-dependent monocyte migration to the lungs and infected tissues.
Copyright © 2023 The Author(s). Published by Elsevier Inc. All rights reserved.

To initiate adaptive immune responses, dendritic cells (DCs) migrate long distances to transport antigens from peripheral tissues to draining lymph nodes employing a so-called ameboid migration mode. Despite its critical importance, the specific molecular mechanisms that regulate DC migration are poorly characterised. Galectins, a family of β-galactoside-binding proteins, constitute a novel mechanism of membrane organisation at the cell surface and, in this way, exert crucial roles in multiple physiological and pathological processes. Nonetheless, the molecular mechanisms that underlie galectin functions are poorly described and their membrane interacting partners are mostly unknown. Here, we report that galectin-9 is required for the dynamic behaviour and motility of DCs. We demonstrate that galectin-9 deficiency results in impaired chemokine-driven and basal DC migration both in human and mouse, suggesting a conserved function for galectin-9. Deficiency in contractility was identified as the underlying mechanism, which could be rescued by restoring membrane-bound galectin-9 levels. Furthermore, we show that galectin-9 controls RhoA activity and downstream signalling, in turn causing rearrangements of the actin cytoskeleton at the cell rear that promote DC efficient migration. Galectin-9 interaction with the adhesion receptor CD44 was required for its function enhancing DC migration. Remarkably, analysis of DC motility in a 3D environment containing a tumour spheroid revealed galectin-9 is required for DC persistent migration towards the tumour and for DC infiltration. Moreover, exogenous galectin-9 rescued the motility of immunocompromised primary blood DCs, revealing a novel role for galectin-9 in the tumour microenvironment, with potential implications for DC-based immunotherapies.