Biology subjects

Innocenti, M.

Publications and source records attributed to Innocenti, M..

4 recordsLinked to original sources

bioRxiv2025

Dual-targeting strategy to repurpose Cetuximab with HFn nanoconjugates for immunotherapy of triple-negative breast cancer

Triple-negative breast cancer (TNBC) is a highly aggressive and treatment-resistant malignancy, characterized by the lack of targeted therapies and poor clinical outcomes. Here, we present a dual-targeting strategy combining the anti-EGFR monoclonal antibody Cetuximab (CTX) with H-ferritin (HFn), a nanoparticle targeting transferrin receptor 1 (TfR1), for potential immunotherapy in CTX-resistant tumors. The HFn-CTX nanoconjugate exhibited favorable biophysical properties, including a hydrodynamic size of <30 nm, and significantly enhanced antibody-dependent cellular cytotoxicity (ADCC) in TNBC spheroids compared to CTX alone. Conversely, glioblastoma spheroids did not exhibit comparable reactivity. This effect correlated with elevated cell-surface EGFR expression and plasma-membrane lingering of the nanoconjugate in TNBC cells, facilitating robust immune activation. Biodistribution studies showed selective accumulation of the HFn-CTX nanoconjugate in TNBC tumors in vivo. These findings highlight the potential of HFn-CTX nanoconjugates to repurpose CTX for refractory cancers that express EGFR at high levels like TNBC, leveraging dual-receptor targeting to amplify immune-mediated cytotoxicity and overcome resistance.

biochemistry↗

bioRxiv2024

Mechanoreceptors initiate innate immunity in response to microbial infections

How mammals mount an effective immune response against infectious agents remains an unresolved fundamental issue in biology. Here, we discovered an unforeseen two-tier mechanism of neutrophil recruitment during infections, in which mechanosensing is key to initiating innate immunity. Leveraging a skin infection model and pathogenic bacteria and fungi, we demonstrate that the early recruitment of neutrophils is mainly danger-driven and partly reminiscent of sterile inflammation. Mechanistically, neutrophil recruitment is initiated by a mechanosensor-dependent pathway, involving the activation of PIEZO1 channels. This leads to LTB4 production, which, along with IL-1, induces the release of CXCL1, promoting neutrophil arrival to the site of infection. In contrast, later neutrophil recruitment is TLR- and CXCL2-dependent, highlighting a shift towards a pathogen-driven response to sustain inflammation. These findings advance our understanding of innate immunity by uncovering that mechanical and biochemical signals integrate into a circuit that initiates innate immune responses to microbial infections.

immunology↗

bioRxiv2024

Arp2/3 complex-dependent actin regulation protects the survival of tissue-resident mast cells

Actin network dynamics are pivotal in governing the motility and effector functions of immune cells. The Arp2/3 complex is a key regulator of actin filament branching, with mutations in its subunits being linked with human immunodeficiencies. While known for its role in phagocytosis and cell migration, our study uncovers a critical role of the Arp2/3 complex in safeguarding the tissue residency of mast cells (MCs), essential immune cells in allergies, venom detoxification and antigen-specific avoidance. Mechanistically, we show that MCs require Arp2/3-regulated actin filament assembly to resist their integrin-mediated mechano-coupling with their tissue niche. Arp2/3 complex depletion directs MCs into cell cycle arrest and death, which can be rescued by inhibiting their mechanical interactions with extracellular matrix. Our findings underscore the Arp2/3 complex as a mechano-protective element for maintaining MC survival and longevity in tissues, highlighting the importance of actin regulation in preserving the homeostasis of a tissue-resident immune cell population. One Sentence SummaryArp2/3 complex protects the tissue homeostasis of resident mast cell networks

immunology↗

bioRxiv2018

CLIC4 is regulated by RhoA-mDia2 signaling through Profilin-1 binding to modulate filopodia length

CLIC4 is a cytosolic protein implicated in diverse actin-based processes, including integrin trafficking, cell adhesion and tubulogenesis. CLIC4 is rapidly recruited to the plasma membrane by G12/13-coupled receptor agonists and then partly co-localizes with {beta}1 integrins. Receptor-mediated CLIC4 translocation depends on actin polymerization, but the mechanism and functional significance of CLIC4 trafficking are unknown. Here we show that RhoA activation by either LPA or EGF is necessary and sufficient for CLIC4 translocation, with a regulatory role for the RhoA effector mDia2, an inducer of actin polymerization. We find that CLIC4 directly interacts with the G-actin-binding protein Profilin-1 via conserved residues that are required for CLIC4 trafficking and lie in a concave surface. Consistently, silencing of Profilin-1 impaired CLIC4 trafficking induced by either LPA or EGF. CLIC4 knockdown promoted the formation of long integrin-dependent filopodia, a phenotype rescued by wild-type CLIC4 but not by trafficking-incompetent CLIC4(C35A). Our results establish CLIC4 as a Profilin-1-binding protein and suggest that CLIC4 translocation provides a feedback mechanism to modulate mDia2/Profilin-1-driven cortical actin assembly and membrane protrusion.

cell biology↗