Biology subjects

De Luca, R.

Publications and source records attributed to De Luca, R..

8 recordsLinked to original sources

bioRxiv2025

Suprachiasmatic Neuromedin-S Neurons Regulate Arousal

Mammalian circadian rhythms, which orchestrate the daily temporal structure of biological processes, including the sleep-wake cycle, are primarily regulated by the circadian clock in the hypothalamic suprachiasmatic nucleus (SCN). The SCN clock is also implicated in providing an arousal signal, particularly during the wake-maintenance zone (WMZ) of our biological day, essential for sustaining normal levels of wakefulness in the presence of mounting sleep pressure. Here we identify a role for SCN Neuromedin-S (SCNNMS) neurons in regulating the level of arousal, especially during the WMZ. We used chemogenetic and optogenetic methods to activate SCNNMS neurons in vivo, which potently drove wakefulness. Fiber photometry confirmed the wake-active profile of SCNNM neurons. Genetically ablating SCNNMS neurons disrupted the sleep-wake cycle, reducing wakefulness during the dark period and abolished the circadian rhythm of body temperature. SCNNMS neurons target the dorsomedial hypothalamic nucleus (DMH), and photostimulation of their terminals within the DMH rapidly produces arousal from sleep. Pre-synaptic inputs to SCNNMS neurons were also identified, including regions known to influence SCN clock regulation. Unexpectedly, we discovered strong input from the preoptic area (POA), which itself receives substantial inhibitory input from the DMH, forming a possible arousal-promoting circuit (SCN->DMH->POA->SCN). Finally, we analyzed the transcriptional profile of SCNNMS neurons via single-nuclei RNA-Seq, revealing three distinct subtypes. Our findings link molecularly-defined SCN neurons to sleep-wake patterns, body temperature rhythms, and arousal control. Significance StatementOur studys findings provide a cellular and neurobiological understanding of how Neuromedin-S (NMS)-containing SCN neurons contribute to regulating circadian rhythms, sleep-wake patterns, body temperature, and arousal control in mammals. This research illuminates the circuit, cellular, and synaptic mechanisms through which SCN neurons regulate daily cycles of wakefulness and sleep, with implications for understanding and potentially manipulating these processes in health and disease.

neuroscience↗

bioRxiv2024

Identifying the Brain Circuits that Regulate Pain-Induced Sleep Disturbances

Pain therapies that alleviate both pain and sleep disturbances may be the most effective for pain relief, as both chronic pain and sleep loss render the opioidergic system, targeted by opioids, less sensitive and effective for analgesia. Therefore, we first studied the link between sleep disturbances and the activation of nociceptors in two acute pain models. Activation of nociceptors in both acute inflammatory (AIP) and opto-pain models led to sleep loss, decreased sleep spindle density, and increased sleep fragmentation that lasted 3 to 6 hours. This relationship is facilitated by the transmission of nociceptive signals through the spino-parabrachial pathways, converging at the wake-active PBelCGRP (parabrachial nucleus expressing Calcitonin Gene-Related Peptide) neurons, known to gate aversive stimuli. However, it has never been tested whether the targeted blocking of this wake pathway can alleviate pain-induced sleep disturbances without increasing sleepiness. Therefore, we next used selective ablations or optogenetic silencing and identified the key role played by the glutamatergic PBelCGRP in pain-induced sleep disturbances. Inactivating the PBelCGRP neurons by genetic deletion or optogenetic silencing prevented these sleep disturbances in both pain models. Furthermore, to understand the wake pathways underlying the pain-induced sleep disturbances, we silenced the PBelCGRP terminals at four key sites in the substantia innominata of the basal forebrain (SI-BF), the central nucleus of Amygdala (CeA), the bed nucleus of stria terminalis (BNST), or the lateral hypothalamus (LH). Silencing of the SI-BF and CeA also significantly reversed pain-induced sleep loss, specifically through the action on the CGRP and NMDA receptors. This was also confirmed by site-specific blockade of these receptors pharmacologically. Our results highlight the significant potential for selectively targeting the wake pathway to effectively treat pain and sleep disturbances, which will minimize risks associated with traditional analgesics. One sentence summaryParabrachial CGRP neurons regulate awakenings to pain.

neuroscience↗

bioRxiv2024

Afferent projections to the Calca/CGRP-expressing parabrachial neurons in mice

The parabrachial nucleus (PB), located in the dorsolateral pons, contains primarily glutamatergic neurons which regulate responses to a variety of interoceptive and cutaneous sensory signals. The lateral PB subpopulation expressing the Calca gene which produces the neuropeptide calcitonin gene-related peptide (CGRP) relays signals related to threatening stimuli such as hypercarbia, pain, and nausea, yet the afferents to these neurons are only partially understood. We mapped the afferent projections to the lateral part of the PB in mice using conventional cholera toxin B subunit (CTb) retrograde tracing, and then used conditional rabies virus retrograde tracing to map monosynaptic inputs specifically targeting the PBCalca/CGRP neurons. Using vesicular GABA (vGAT) and glutamate (vGLUT2) transporter reporter mice, we found that lateral PB neurons receive GABAergic afferents from regions such as the lateral part of the central nucleus of the amygdala, lateral dorsal subnucleus of the bed nucleus of the stria terminalis, substantia innominata, and the ventrolateral periaqueductal gray. Additionally, they receive glutamatergic afferents from the infralimbic and insular cortex, paraventricular nucleus, parasubthalamic nucleus, trigeminal complex, medullary reticular nucleus, and nucleus of the solitary tract. Using anterograde tracing and confocal microscopy, we then identified close axonal appositions between these afferents and PBCalca/CGRP neurons. Finally, we used channelrhodopsin-assisted circuit mapping to test whether some of these inputs directly synapse upon the PBCalca/CGRP neurons. These findings provide a comprehensive neuroanatomical framework for understanding the afferent projections regulating the PBCalca/CGRP neurons.

neuroscience↗

bioRxiv2023

A spatially-resolved transcriptional atlas of the murine dorsal pons at single-cell resolution

The "dorsal pons", or "dorsal pontine tegmentum" (dPnTg), is part of the brainstem. It is a complex, densely packed region whose nuclei are involved in regulating many vital functions. Notable among them are the parabrachial nucleus, the Kolliker Fuse, the Barrington nucleus, the locus coeruleus, and the dorsal, laterodorsal, and ventral tegmental nuclei. In this study, we applied single-nucleus RNA-seq (snRNA-seq) to resolve neuronal subtypes based on their unique transcriptional profiles and then used multiplexed error robust fluorescence in situ hybridization (MERFISH) to map them spatially. We sampled [~]1 million cells across the dPnTg and defined the spatial distribution of over 120 neuronal subtypes. Our analysis identified an unpredicted high transcriptional diversity in this region and pinpointed many neuronal subtypes unique marker genes. We also demonstrated that many neuronal subtypes are transcriptionally similar between humans and mice, enhancing this studys translational value. Finally, we developed a freely accessible, GPU and CPU-powered dashboard (http://harvard.heavy.ai:6273/) that combines interactive visual analytics and hardware-accelerated SQL into a data science framework to allow the scientific community to query and gain insights into the data.

neuroscience↗

bioRxiv2020

Antibody-based delivery of Interleukin-9 to neovascular structures: therapeutic evaluation in cancer and arthritis

Interleukin-9 (IL9) is a cytokine with multiple functions, including the ability to activate group 2 innate lymphoid cells (ILC2s), which has been postulated to be therapeutically active in mouse models of arthritis. Similarly, IL9 has been suggested to play an important role in tumor immunity. Here, we describe the cloning, expression and characterization of three fusion proteins based on murine IL9 and the F8 antibody, specific to the alternatively-spliced EDA domain of fibronectin. EDA is strongly expressed in cancer and in various arthritic conditions, while being undetectable in the majority of healthy organs. IL9-based fusion proteins with an irrelevant antibody specific to hen egg lysozyme served as negative control in our study. The fusion proteins were characterized by quantitative biodistribution analysis in tumor-bearing mice using radioiodinated protein preparations. The highest tumor uptake and best tumor:organ ratios were observed for a format, in which the IL9 moiety was flanked by two units of the F8 antibody in single-chain Fv format. Biological activity of IL9 was retained when the payload was fused to antibodies. However, the targeted delivery of IL9 to the disease site resulted in a modest anti-tumor activity in three different murine models of cancer (K1735M2, CT26 and F9), while no therapeutic benefit was observed in a collagen induced model of arthritis. Collectively, these results confirm the possibility to deliver IL9 to the site of disease but cast doubts about the alleged therapeutic activity of this cytokine in cancer and arthritis, which has been postulated in previous publications.

bioengineering↗

bioRxiv2019

The immunocytokine L19-TNF eradicates Sarcomas in combination with Chemotherapy or with immune check-point inhibitors

Antibody-cytokine fusion proteins (also called "immunocytokines") represent an emerging class of biopharmaceutical products, which are being considered for cancer immunotherapy. When used as single agents, pro-inflammatory immunocytokines are rarely capable of induce complete and durable cancer regression in mouse models and in patients. However, the combination treatment with conventional chemotherapy or with other immune-stimulatory agents typically increases the therapeutic efficacy of immunocytokines. In this article, we describe combination treatments of a tumor-targeting antibody-cytokine fusion protein based on the L19 antibody (specific to a splice isoform of fibronectin) fused to murine tumor necrosis factor (TNF) with standard chemotherapy (dacarbazine, trabectedin or melphalan) or with an immune check-point inhibitor (anti-PD-1) in a BALB/c derived immunocompetent murine model of sarcoma (WEHI-164). All combination treatments led to improved tumor remission compared to single agent treatments, suggesting that these combination partners may be suitable for further clinical development in sarcoma patients.

cancer biology↗

bioRxiv2019

A novel fully-human potency-matched dual cytokine-antibody fusion protein targets carbonic anhydrase IX in renal cell carcinomas

Certain cytokines synergize in activating anti-cancer immunity at the site of disease and it may be desirable to generate biopharmaceutical agents, capable of simultaneous delivery of cytokine pairs to the tumor. In this article, we have described the cloning, expression and characterization of IL2-XE114-TNFmut, a dual-cytokine biopharmaceutical featuring the sequential fusion of interleukin-2 (IL2) with the XE114 antibody in scFv format and a tumor necrosis factor mutant (TNFmut). The fusion protein recognized the cognate antigen (carbonic anhydrase IX, a marker of hypoxia and of renal cell carcinoma) with high affinity and specificity. IL2-XE114-TNFmut formed a stable non-covalent homotrimeric structure, displayed cytokine activity in in vitro tests and preferentially localized to solid tumors in vivo. The product exhibited a partial growth inhibition of murine CT26 tumors transfected for carbonic anhydrase IX. When administered to Cynomolgus monkey as intravenous injection, IL2-XE114-TNFmut showed the expected plasma concentration of ~1500 ng/ml at early time points, indicating the absence of any in vivo trapping events, and a half-life of ~2 hours. IL2-XE114-TNFmut may thus be considered as a promising biopharmaceutical for the treatment of metastatic clear-cell renal cell carcinoma, since these tumors are known to be sensitive to IL2 and to TNF.\n\nContribution to the fieldThere is a growing interest in the antibody-based targeted delivery of pro-inflammatory cytokines for tumor therapy, which may be complementary or alternative to immune checkpoint inhibitors for immunotherapeutic applications. In this article, we have described a novel fusion protein, featuring antibody moieties specific to carbonic anhydrase IX, as well as interleukin-2 and tumor necrosis factor as pro-inflammatory cytokines, which combines the ability to recognize a tumor-associated antigen on the surface of renal cell carcinomas with the simultaneous display of two potent therapeutic payloads. The newly developed product (termed IL2-XE114-TNFmut) exhibited favorable biochemical characteristics, the ability to preferentially localize at the tumor site, a cancer growth inhibition activity and a suitable pharmacokinetic profile in Cynomolgus monkey. IL2-XE114-TNFmut may therefore represent an attractive candidate for the immunotherapy of renal cell carcinoma.

bioengineering↗

bioRxiv2019

Comparative evaluation of bolus and fractionated administration modalities for two antibody-cytokine fusions in immunocompetent tumor-bearing mice

Antibody-cytokine fusion proteins are being considered as biopharmaceuticals for cancer immunotherapy. Tumor-homing cytokine fusions typically display an improved therapeutic activity compared to the corresponding unmodified cytokine products, but toxicity profiles at equivalent doses are similar, since side effects are mainly driven by the cytokine concentration in blood. In order to explore avenues to harness the therapeutic potential of antibody-cytokine fusions while decreasing potential toxicity, we compared bolus and fractionated administration modalities for two tumor-targeting antibody-cytokine fusion proteins based on human interleukin-2 (IL2) and murine tumor necrosis factor (TNF) (i.e., L19-hIL2 and L19-mTNF) in two murine immunocompetent mouse models of cancer (F9 and C51). A comparative quantitative biodistribution analysis with radio-labeled protein preparations revealed that a fractionated administration of L19-hIL2 could deliver comparable product doses to the tumor with decreased product concentration in blood and normal organs, compared to bolus injection. By contrast, L19-mTNF (a product that causes a selective vascular shutdown in the tumor) accumulated most efficiently after bolus injection. Fractionated schedules allowed the safe administration of a cumulative dose of L19-mTNF, which was 2.5-times higher than the lethal dose for bolus injection. Dose fractionation led to a prolonged tumor growth inhibition for F9 teratocarcinomas, but not for C51 colorectal tumors, which responded best to bolus injection. Thus, dose fractionation may have different outcomes for the same antibody-cytokine product in different biological contexts.

pharmacology and toxicology↗