Biology subjects

Procissi, D.

Publications and source records attributed to Procissi, D..

7 recordsLinked to original sources

bioRxiv2026

p38β/MAPK11 Deficiency Exacerbates Cardiac Structural and Electrophysiological Remodeling and Contributes to Immune Dysregulation in the Aging Heart

Aging is a major risk factor for cardiac diseases, including heart failure, myocardial infarction, and arrhythmias. Activation of p38 MAPKs regulates cardiac remodeling and contributes to age-related cardiac dysfunction. However, the isoform-specific roles of p38 kinases in the aging heart remain poorly understood. Although p38{beta} has been reported to exert cardioprotective effects in models of doxorubicin-induced cardiotoxicity and ischemia-reperfusion, its role in cardiac aging remains unclear. Here, we investigated the role of p38{beta} using p38{beta} germline knockout (p38{beta}-/-) mice. Aged p38{beta}-/- mice exhibited increased LV hypertrophy, QT prolongation, calcium mishandling, heightened susceptibility to arrhythmias, increased myocardial fibrosis, and an altered inflammatory microenvironment, compared with age-matched wild-type controls. Transcriptomic profiling revealed that p38{beta} deletion reprograms the cardiac transcriptome in aged mice, suppressing innate immune and proteostasis-related pathways while promoting adaptive immune activation, developmental, extracellular vesicle-mediated, and ion-transport pathways. Collectively, these findings identify p38{beta} as a critical regulator of structural, electrophysiological, and immune homeostasis in the aging heart and demonstrate that its loss promotes maladaptive remodeling and arrhythmogenic vulnerability. NEW AND NOTEWORTHYWe identify p38{beta} as a previously unrecognized regulator of cardiac aging. Systemic loss of p38{beta} disrupts structural, electrophysiological, and immune homeostasis in the aging heart, revealing its protective role in maintaining cardiac function with age. These findings underscore the importance of isoform-specific p38 signaling and suggest that broadly targeting p38 MAPKs may have unintended consequences in age-related cardiovascular diseases.

physiology↗

bioRxiv2024

A Bi-Specific T Cell-Engaging Antibody Shows Potent Activity, Specificity, and Tumor Microenvironment Remodeling in Experimental Syngeneic and Genetically Engineered Models of GBM

BackgroundBispecific T cell-engagers (BTEs) are engineered antibodies that redirect T cells to target antigen-expressing tumors. BTEs targeting tumor-specific antigens such as interleukin 13 receptor alpha 2 (IL13R2) and EGFRvIII have been developed for glioblastoma (GBM). However, there is limited mechanistic understanding of the action of BTE since prior studies were mostly conducted in immunocompromised animal models. To close this gap, the function of BTEs was assessed in the immunosuppressive glioma microenvironment (TME) of orthotopic and genetically engineered mouse models (GEMM) with intact immune systems. MethodsA BTE that bridges CD3 epsilon on murine T cells to IL13R2-positive GBM cells was developed and the therapeutic mechanism investigated in immunocompetent mouse models of GBM. Multi-color flow cytometry, single-cell RNA sequencing (scRNA-Seq), multiplex immunofluorescence, and multiparametric magnetic resonance imaging (MRI) across multiple pre-clinical models of GBM were used to evaluate the mechanism and action and response. ResultsBTE-mediated interactions between murine T cells and GBM cells triggered T cell activation and antigen-dependent killing of GBM cells. BTE treatment significantly extended the survival of mice bearing IL13R2-expressing orthotopic glioma and de novo forming GBM in the GEMM. Quantified parametric MR imaging validated the survival data showing a reduction in glioma volume and decreased glioma viability. Flow cytometric and scRNA-seq analyses of the TME revealed robust increases in activated and memory T cells and decreases in immunosuppressive myeloid cells in the brains of mice following BTE treatment. ConclusionsOur data demonstrate that the survival benefits of BTEs in preclinical models of glioma are due to the ability to engage the host immune system in direct killing, induction of immunological memory, and modulation of the TME. These findings provide a deeper insight into the mechanism of BTE actions in GBM. WHAT IS ALREADY KNOWN ABOUT THIS TOPICBi-specific T cell engaging antibodies (BTEs) targeting IL13R2 and EGFRvIII have been developed and shown to activate T cells that mediate killing of glioma cells in vitro and in in vivo. WHAT THIS STUDY ADDSBy using immune competent preclinical models, this study reveals that BTEs trigger in situ tumor immune memory within the central nervous system. HOW THIS STUDY MIGHT AFFECT RESEARCH, PRACTICE OR POLICYInsights into the mechanism of action of BTEs inform response biomarkers that should be considered for inclusion in window-of-opportunity clinical trial assessments and for the rational selection of future combinatorial strategies.

immunology↗

bioRxiv2024

Hypoxia inducible factors drive miRNA-mediated downregulation of L2HGDH and HIF1A in clear cell renal cancer independent of 14q deletion

Clear cell renal cell carcinoma (ccRCC) is characterized by pseudohypoxic signaling as well as metabolic and epigenetic aberrations of increasing severity during its pathogenesis and progression. Upon identifying that the markedly lower expression of L2HGDH and HIF1A in ccRCC tumors is not explained only by 14q deletion (40% of ccRCC), we sought to elucidate the mechanisms underscoring their down-regulation independent of 14q deletion, given the marked translational and scientific importance. While lower L2HGDH was found to portend a strikingly worse prognosis in a multivariate survival analysis of ccRCC patients (n=509; TCGA) highlighting its translational importance, the lower expression of HIF1A in ccRCC despite the upregulated HIF1 protein (secondary to VHL loss) is of significant scientific interest. Using a comprehensive array of in vitro assays with genetic manipulation, clinicogenomic bioinformatic analyses of large ccRCC datasets, and the Cdh16-Cre Vhl-fl mouse model with kidney specific Vhl-loss, we demonstrate that the downregulation of both L2HGDH and HIF1A in ccRCC is driven by the hypoxia-inducible factors via miR21-3p and miR155-5p, respectively, during pathogenesis and progression. In doing so, we unveil a conserved inhibitory feedback loop for HIF1A in ccRCC (HIFs[->]miR155[->]HIF1A), providing a mechanistic explanation for HIF1A downregulation despite elevated HIF1 protein. Furthermore, and most importantly, we show that inhibition of hypoxia-inducible factors reverses the adverse loss of L2HGDH and hydroxymethylcytosine in ccRCC, implicating both HIF2 and HIF1 in these metabolic-epigenetic aberrations. Translational StatementThis study demonstrates that hypoxia-inducible factors (HIFs) drive early and sustained metabolic and epigenetic dysregulation in clear cell renal cell carcinoma (ccRCC). Notably, these aberrations begin early in carcinogenesis. We show that inhibition of HIFs can reverse these pathological changes - most significantly, restoring levels of 5-hydroxymethylcytosine, a key epigenetic marker lost in ccRCC due to metabolic inhibition of TET enzymes. Our findings support the integration of HIF2 inhibition earlier in the therapeutic approach for advanced ccRCC. Moreover, the data suggest that dual inhibition of HIF2 and HIF1 - particularly in tumors with high expression of both factors - may yield a more robust reversal of epigenetic abnormalities and merits further investigation. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=189 HEIGHT=200 SRC="FIGDIR/small/625494v2_ufig1.gif" ALT="Figure 1"> View larger version (85K): org.highwire.dtl.DTLVardef@a75aborg.highwire.dtl.DTLVardef@b36704org.highwire.dtl.DTLVardef@3057c4org.highwire.dtl.DTLVardef@1d24074_HPS_FORMAT_FIGEXP M_FIG C_FIG

cancer biology↗

bioRxiv2022

Low Level Whole-Brain Radiation Enhances Theranostic Potential Of Single Domain Antibody Fragments For HER2-Positive Brain Metastases

BackgroundSingle-domain antibody fragments (aka VHH, [~]13 kDa) are promising delivery systems for brain tumor theranostics; however, achieving efficient delivery of VHH to intracranial lesions remains challenging due to the tumor-brain barrier. Here, we evaluate low-dose whole-brain irradiation as a strategy to increase the delivery of an anti-HER2 VHH to breast cancer-derived intracranial tumors in mice. MethodsMice with intracranial HER2-positive BT474BrM3 tumors received 10-Gy fractionated cranial irradiation and evaluated using non-invasive imaging methods. The anti-HER2 VHH 5F7 was labeled with 18F, administered intravenously to irradiated mice and controls, and PET/CT imaging was conducted at various intervals after irradiation. Tumor uptake of 18F-labeled 5F7 in irradiated and control mice was compared by PET/CT image analysis and correlated with tumor volumes. In addition, longitudinal dynamic contrast-enhanced MRI (DCE-MRI) was conducted to visualize and quantify the potential effects of radiation on tumor perfusion and permeability. ResultsIncreased 18F-labeled 5F7 intracranial tumor uptake was observed with PET in mice that received cranial irradiation, with maximum tumor accumulation seen approximately 12 days post initial radiation treatment. No radiation-induced changes in HER2 expression were detected by Western blot, flow cytometry, or on tissue sections. DCE-MRI imaging demonstrated transiently increased tumor perfusion and permeability after irradiation, consistent with the higher tumor uptake of 18F-labeled anti-HER2 5F7 in irradiated mice. ConclusionLow-level brain irradiation induces dynamic changes in tumor vasculature that increase the intracranial tumor delivery of an anti-HER2 VHH, which could facilitate the use of labeled sdAb to detect, monitor, and treat HER2-expressing brain metastases. Key pointsO_LILow-level radiation enhances uptake of HER2-specific VHH in intracranial tumors. C_LIO_LIXRT + radiolabeled VHH shows promise as a treatment strategy for breast cancer brain metastases. C_LI Importance of the StudyImproving the detection and treatment of brain metastases (BM) that overexpress human epidermal growth factor receptor type 2 (HER2) is an urgent medical need. Drug delivery to BM is confounded by their tumor vasculature, which is more restrictive than in GBM. Single domain antibody fragments, about one-tenth the size of antibodies, could be promising theranostic vectors for BM provided sufficient BM uptake could be achieved. In this study, we utilized longitudinal PET imaging to demonstrate that low-dose whole-brain irradiation (WBRT) significantly increased 18F-labeled HER2-specific 5F7 VHH uptake in intracranial HER2-positive tumors in mice. Combining low dose WBRT with 5F7 VHH labeled with -or {beta}-particle emitting radionuclides could provide an effective and specific targeted radiotherapeutic strategy for treating patients with HER2-expressing BM.

cancer biology↗

bioRxiv2020

Neural Stem Cells Secreting Bispecific T Cell Engager to Induce Selective Anti-Glioma Activity

Glioblastoma (GBM) is the most lethal primary brain tumor in adults. There is no treatment that provides durable relief for the vast majority of GBM patients. In this study, weve tested a bispecific antibody comprised of single-chain variable regions (scFvs) against T cell CD3{varepsilon} and GBM cell interleukin 13 receptor alpha 2 (IL13R2). We demonstrate that this BiTE (BiTELLON) engages peripheral and tumor-infiltrating lymphocytes harvested from patients tumors, and in so doing exerts anti-GBM activity ex vivo. The interaction of BiTELLON with T cells and engagement of IL13R2-expressing GBM cells stimulates T cell proliferation as well as production of pro-inflammatory cytokines INF{gamma} and TNF. We have modified neural stem cells (NSCs) to produce and secrete the BiTE (NSCsLLON). When injected intracranially in mice with brain tumor, NSCsLLON show tropism for tumor, secrete BiTELLON, and remain viable for several days. When injected directly into tumor, NSCLLON provide significant survival benefit to mice bearing IL13R2+ GBM. Our results support further investigation and development of this therapeutic for clinical translation.

immunology↗

bioRxiv2018

Monocyte depletion attenuates the development of posttraumatic hydrocephalus and preserves white matter integrity after traumatic brain injury

Monocytes are amongst the first cells recruited into the brain after traumatic brain injury (TBI). We have shown monocyte depletion 24 hours prior to TBI reduces brain edema, decreases neutrophil infiltration and improves behavioral outcomes. Additionally, both lesion and ventricle size correlate with poor neurologic outcome after TBI. Therefore, we aimed to determine the association between monocyte infiltration, lesion size, and ventricle volume. We hypothesized that monocyte depletion would attenuate lesion size, decrease ventricle enlargement, and preserve white matter in mice after TBI. C57BL/6 mice underwent pan monocyte depletion via intravenous injection of liposome-encapsulated clodronate. Control mice were injected with liposome-encapsulated PBS. TBI was induced via an open-head, controlled cortical impact. Mice were imaged using magnetic resonance imaging (MRI) at 1, 7, and 14 days post-injury to evaluate progression of lesion and to detect morphological changes associated with injury (3D T1- weighted MRI) including regional alterations in white matter patterns (multi-direction diffusion MRI). Lesion size and ventricle volume were measured using semi-automatic segmentation and active contour methods with the software program ITK-SNAP. Data was analyzed with the statistical software program PRISM. No significant effect of monocyte depletion on lesion size was detected using MRI following TBI (p=0.4). However, progressive ventricle enlargement following TBI was observed to be attenuated in the monocyte-depleted cohort (5.3 {+/-} 0.9mm3) as compared to the sham-depleted cohort (13.2 {+/-} 3.1mm3; p=0.02). Global white matter integrity and regional patterns were evaluated and quantified for each mouse after extracting fractional anisotropy maps from the multi-direction diffusion-MRI data using Siemens Syngo DTI analysis package. Fractional anisotropy values were preserved in the monocyte-depleted cohort (123.0 {+/-} 4.4mm3) as compared to sham-depleted mice (94.9 {+/-} 4.6mm3; p=0.025) by 14 days post-TBI. The MRI derived data suggests that monocyte depletion at the time of injury may be a novel therapeutic strategy in the treatment of TBI. Furthermore, non-invasive longitudinal imaging allows for the evaluation of both TBI progression as well as therapeutic response over the course of injury.

neuroscience↗

bioRxiv2018

Dorsal Hippocampal Activation Suppresses Neuropathic Pain Behaviors: Chronic pain as extinction-resistant pain-related memory traces

Accumulating evidence suggests the hippocampus being involved in, and modified with, chronic neuropathic pain. However, it is still not clear whether hippocampal activity has direct control over neuropathic behaviors. Here we show that activation of the dorsal, but not ventral, hippocampus, by glutamate microinjection or by chemogenetically increasing excitability (PSAM/PSEM), completely or partially reversed neuropathic behaviors: tactile allodynia and thermal hyperalgesia in the models of spared nerve injury and lumbar spinal nerve ligation. Using a new methodology (chemo-fMRI), where we combine awake resting state brain imaging with viral vector mediated chemogenetic activation (PSAM/PSEM), we could demonstrate that increased excitability of dorsal hippocampus neurons altered resting state functional connectivity within circuitry specifically related to the extent of diminution of neuropathic behavior (tactile allodynia). The identified circuitry most reliably (survived a validation procedure) identified dorsal hippocampal connections to the somatosensory cortex and the thalamus. Moreover, anterograde tracing indicated non-overlapping projections from dorsal and ventral hippocampus. Thus, the present study exhibits a novel causal role for the dorsal hippocampus, and mediating circuitry, controlling neuropathic pain-related behaviors. Altogether, these results imply downregulation of dorsal hippocampus circuitry in chronic neuropathic pain; the activation of which reverses pain behaviors either through disruption of accumulated memories and/or by enhancing extinction circuitry.

neuroscience↗