RESUMEN

T cell-based immunotherapies are a promising therapeutic approach for multiple malignancies, but their efficacy is limited by tumor hypoxia arising from dysfunctional blood vessels. Here, we report that cell-intrinsic properties of a single vascular component, namely the pericyte, contribute to the control of tumor oxygenation, macrophage polarization, vessel inflammation, and T cell infiltration. Switching pericyte phenotype from a synthetic to a differentiated state reverses immune suppression and sensitizes tumors to adoptive T cell therapy, leading to regression of melanoma in mice. In melanoma patients, improved survival is correlated with enhanced pericyte maturity. Importantly, pericyte plasticity is regulated by signaling pathways converging on Rho kinase activity, with pericyte maturity being inducible by selective low-dose therapeutics that suppress pericyte MEK, AKT, or notch signaling. We also show that low-dose targeted anticancer therapy can durably change the tumor microenvironment without inducing adaptive resistance, creating a highly translatable pathway for redosing anticancer targeted therapies in combination with immunotherapy to improve outcome.

Asunto(s)

RESUMEN

Cosmic radiation experienced during space travel may increase the risk of cognitive impairment. While simulated galactic cosmic radiation (GCRsim) has led to memory deficits in wildtype (WT) mice, it has not been investigated whether GCRsim in combination with genetic risk factors for Alzheimer's disease (AD) worsens memory further in aging mice. Here, we investigated the central nervous system (CNS) effects of 0 Gy (sham) or 0.75 Gy five-ion GCRsim or 2 Gy gamma radiation (IRR) in 14-month-old female and male APPNL-F/NL-F knock-in (KI) mice bearing humanized ApoE3 or ApoE4 (APP;E3F and APP;E4F). As travel to a specialized facility was required for irradiation, both traveled sham-irradiated C57BL/6J WT and KI mice and non-traveled (NT) KI mice acted as controls for potential effects of travel. Mice underwent four behavioral tests at 20 months of age and were euthanized for pathological and biochemical analyses 1 month later. Fecal samples were collected pre- and post-irradiation at four different time points. GCRsim seemed to impair memory in male APP;E3F mice compared to their sham counterparts. Travel tended to improve cognition in male APP;E3F mice and lowered total Aß in female and male APP;E3F mice compared to their non-traveled counterparts. Sham-irradiated male APP;E4F mice accumulated more fibrillar amyloid than their APP;E3F counterparts. Radiation exposure had only modest effects on behavior and brain changes, but travel-, sex-, and genotype-specific effects were seen. Irradiated mice had immediate and long-term differences in their gut bacterial composition that correlated to Alzheimer's disease phenotypes.

Asunto(s)

RESUMEN

BACKGROUND: Intrahepatic cholangiocarcinoma (iCCA) is a lethal primary liver tumor characterized by clinical aggressiveness, poor prognosis, and scarce therapeutic possibilities. Therefore, new treatments are urgently needed to render this disease curable. Since cumulating evidence supports the oncogenic properties of the Heat Shock Factor 1 (HSF1) transcription factor in various cancer types, we investigated its pathogenetic and therapeutic relevance in iCCA. METHODS: Levels of HSF1 were evaluated in a vast collection of iCCA specimens. The effects of HSF1 inactivation on iCCA development in vivo were investigated using three established oncogene-driven iCCA mouse models. In addition, the impact of HSF1 suppression on tumor cells and tumor stroma was assessed in iCCA cell lines, human iCCA cancer-associated fibroblasts (hCAFs), and patient-derived organoids. RESULTS: Human preinvasive, invasive, and metastatic iCCAs displayed widespread HSF1 upregulation, which was associated with a dismal prognosis of the patients. In addition, hydrodynamic injection of a dominant-negative form of HSF1 (HSF1dn), which suppresses HSF1 activity, significantly delayed cholangiocarcinogenesis in AKT/NICD, AKT/YAP, and AKT/TAZ mice. In iCCA cell lines, iCCA hCAFs, and patient-derived organoids, administration of the HSF1 inhibitor KRIBB-11 significantly reduced proliferation and induced apoptosis. Cell death was profoundly augmented by concomitant administration of the Bcl-xL/Bcl2/Bcl-w inhibitor ABT-263. Furthermore, KRIBB-11 reduced mitochondrial bioenergetics and glycolysis of iCCA cells. CONCLUSIONS: The present data underscore the critical pathogenetic, prognostic, and therapeutic role of HSF1 in cholangiocarcinogenesis.

Asunto(s)

RESUMEN

The development of therapeutic strategies to reduce impairments following spinal cord injury (SCI) motivates an active area of research, because there are no effective therapies. One strategy is to address injury-induced demyelination of spared axons by promoting endogenous or exogenous remyelination. However, previously, we showed that new myelin was not necessary to regain hindlimb stepping following moderate thoracic spinal cord contusion in 3-month-old mice. The present analysis investigated two potential mechanisms by which animals can re-establish locomotion in the absence of remyelination: compensation through intact white matter and conduction through spared axons. We induced a severe contusion injury to reduce the spared white matter rim in the remyelination deficient model, with no differences in recovery between remyelination deficient animals and injured littermate controls. We investigated the nodal properties of the axons at the lesion and found that in the remyelination deficient model, axons express the Nav1.2 voltage-gated sodium channel, a sub-type not typically expressed at mature nodes of Ranvier. In a moderate contusion injury, conduction velocities through the lesions of remyelination deficient animals were similar to those in animals with the capacity to remyelinate after injury. Detailed gait analysis and kinematics reveal subtle differences between remyelination deficient animals and remyelination competent controls, but no worse deficits. It is possible that upregulation of Nav1.2 channels may contribute to establishing conduction through the lesion. This conduction could contribute to compensation and regained motor function in mouse models of SCI. Such compensatory mechanism may have implications for interpreting efficacy results for remyelinating interventions in mice and the development of therapies for improving recovery following SCI.

RESUMEN

The field of experimental microsurgery was pioneered by the great microsurgeon Sun Lee, who developed the foundation of transplant surgery in the clinic. Dr Lee also played a seminal role in introducing microsurgery to establish mouse models of cancer. In 1990, at the age of 70, Dr Lee demonstrated microsurgery techniques to the mouse-model team at AntiCancer Inc., leading to the development of the surgical orthotopic implant (SOI) technique and the first orthotopic mouse models of cancer that metastasized in a pattern similar to clinical cancer. At the beginning of the present century, one of us (NY) from Kanazawa University School of Medicine became a visiting scientist at AntiCancer to learn SOI and develop mouse models of cancer using cancer cells expressing fluorescent reporter genes, such as green fluorescent protein (GFP) and red fluorescent protein (RFP), in order to image metastatic cancer cells trafficking in real time. Since then, a total of eight young surgeons from Kanazawa University have been visiting researchers at AntiCancer, developing SOI mouse models of cancer to visualize cancer cells in vivo, tracking all stages of metastasis in real time. The present perspective review summarizes this seminal work, which has revolutionized the field of metastasis research.

RESUMEN

Medulloblastoma is a heterogeneous embryonal tumor of the cerebellum comprised of four distinct molecular subgroups that differ in their developmental origins, genomic landscapes, clinical presentation, and survival. Recent characterization of the human fetal cerebellum at single-cell resolution has propelled unprecedented insights into the cellular origins of medulloblastoma subgroups, including those underlying previously elusive groups 3 and 4. In this review, the molecular pathogenesis of medulloblastoma is examined through the lens of cerebellar development. In addition, we discuss how enhanced understanding of medulloblastoma origins has the potential to refine disease modeling for the advancement of treatment and outcomes.

RESUMEN

Pancreatic cancer is associated with an oncogenic KRAS mutation in approximately 90% of cases. However, a non-negligible proportion of pancreatic cancer cases harbor wild-type KRAS (KRAS-WT). This study establishes genetically engineered mouse models that develop spontaneous pancreatic cancer in the context of KRAS-WT. The Trp53loxP/loxP;Smad4loxP/loxP;Pdx1-Cre (PPSSC) mouse model harbors KRAS-WT and loss of Trp53/Smad4. The Trp53loxP/loxP;Tgfbr2loxP/loxP;Pdx1-Cre (PPTTC) mouse model harbors KRAS-WT and loss of Trp53/Tgfbr2. We identify that either Trp53/Smad4 loss or Trp53/Tgfbr2 loss can induce spontaneous pancreatic tumor formation in the absence of an oncogenic KRAS mutation. The Trp53/Smad4 loss and Trp53/Tgfbr2 loss mouse models exhibit distinct pancreatic tumor histological features, as compared to oncogenic KRAS-driven mouse models. Furthermore, KRAS-WT pancreatic tumors with Trp53/Smad4 loss reveal unique histological features of pancreatic adenosquamous carcinoma (PASC). Single-cell RNA sequencing (scRNA-seq) analysis reveals the distinct tumor immune microenvironment landscape of KRAS-WT (PPSSC) pancreatic tumors as compared with that of oncogenic KRAS-driven pancreatic tumors.

RESUMEN

Fibronectin (FN) serves as a critical organizer of extracellular matrix networks in two principal isoforms, the plasma FN and the cellular FN. While FN's pivotal role in various organ systems, including the blood vasculature, is well-established, its contribution to the development of the skeletal system is much less explored. Furthermore, the pathomechanisms of spondyloepiphyseal dysplasia caused by FN mutations remain elusive. In this minireview, we discuss findings from our recent two studies using i) an iPSC-based cell culture model to explore how FN mutations in spondyloepiphyseal dysplasia impact mesenchymal cell differentiation into chondrocytes and ii) conditional FN knockout mouse models to determine the physiological roles of FN isoforms during postnatal skeletal development. The data revealed that FN mutations cause severe intracellular and matrix defects in mesenchymal cells and impair their ability to differentiate into chondrocytes. The findings further demonstrate the important roles of both FN isoforms in orchestrating regulated chondrogenesis during skeletal development. We critically discuss the findings in the context of the existing literature.

RESUMEN

The mouse is the mammalian model of choice for investigating cardiovascular biology, given our ability to manipulate it by genetic, pharmacologic, mechanical, and environmental means. Imaging is an important approach to phenotyping both function and structure of cardiac and vascular components. This review details commonly used imaging approaches, with a focus on echocardiography and magnetic resonance imaging, with brief overviews of other imaging modalities. In this update, we also emphasize the importance of rigor and reproducibility in imaging approaches, experimental design, and documentation. Finally, we briefly outline emerging imaging approaches but caution that reliability and validity data may be lacking. © 2024 Wiley Periodicals LLC.

Asunto(s)

RESUMEN

Autism spectrum disorders (ASD) are a heterogenous set of syndromes characterised by social impairment and cognitive symptoms. Currently, there are limited treatment options available to help people with ASD manage their symptoms. Understanding the biological mechanisms that result in ASD diagnosis and symptomatology is an essential step in developing new interventional strategies. Human genetic studies have identified common gene variants of small effect and rare risk genes and copy number variants (CNVs) that substantially increase the risk of developing ASD. Reverse translational studies using rodent models based on these genetic variants provide new insight into the biological basis of ASD. Here we review recent findings from three ASD associated CNV mouse models (16p11.2, 2p16.3 and 22q11.2 deletion) that show behavioural and cognitive phenotypes relevant to ASD. These models have identified disturbed excitation-inhibition neurotransmitter balance, evidenced by dysfunctional glutamate and GABA signalling, as a key aetiological mechanism. These models also provide emerging evidence for serotoninergic neurotransmitter system dysfunction, although more work is needed to clarify the nature of this. At the brain network level, prefrontal cortex (PFC) dysfunctional connectivity is also evident across these models, supporting disturbed PFC function as a key nexus in ASD aetiology. Overall, published data highlight the utility and valuable insight gained into ASD aetiology from preclinical CNV mouse models. These have identified key aetiological mechanisms that represent putative novel therapeutic targets for the treatment of ASD symptoms, making them useful translational models for future drug discovery, development and validation.

RESUMEN

Acute kidney injury (AKI) and chronic kidney disease (CKD) are significant public health issues associated with a long-term increase in mortality risk, resulting from various etiologies including renal ischemia, sepsis, drug toxicity, and diabetes mellitus. Numerous preclinical models have been developed to deepen our understanding of the pathophysiological mechanisms and therapeutic approaches for kidney diseases. Among these, rodent models have proven to be powerful tools in the discovery of novel therapeutics, while the development of kidney organoids has emerged as a promising advancement in the field. This review provides a comprehensive analysis of the construction methodologies, underlying biological mechanisms, and recent therapeutic developments across different AKI and CKD models. Additionally, this review summarizes the advantages, limitations, and challenges inherent in these preclinical models, thereby contributing robust evidence to support the development of effective therapeutic strategies.

Asunto(s)

RESUMEN

Alopecia areata is the second most common form of hair loss in humans after androgenetic alopecia. Although a variety of animal models for alopecia areata have been described, currently the C3H/HeJ mouse model is the most commonly used and accepted. Spontaneous hair loss occurs in 15%-25% of older mice in which the lesions wax and wane, similar to the human disease, with alopecia being more common and severe in female mice. Full-thickness skin grafts from mice with spontaneous alopecia areata to young, normal-haired, histocompatible mice provide a highly reproducible model with progressive lesions that makes it useful for drug efficacy and mechanism-based studies. As alopecia areata is a cell-mediated autoimmune disease, transfer of cultured lymph node cells from affected mice to unaffected, histocompatible recipients also promotes disease development and provides an alternative, nonsurgical protocol. Protocols are presented to produce these models such that they can be used to study alopecia areata and to develop novel drug therapies. © 2024 The Author(s). Current Protocols published by Wiley Periodicals LLC. Basic Protocol 1: Full-thickness skin grafts to reproducibly induce alopecia areata in C3H/HeJ mice Basic Protocol 2: Adoptive transfer of cultured lymphoid cells provides a nonsurgical method to induce alopecia areata in C3H/HeJ mice.

Asunto(s)

RESUMEN

Compared to the rapidly growing literature on transcranial electrical stimulation (tES) in humans, research into the mechanisms underlying neuromodulation by tES using in-vivo animal models is growing but still relatively rare. Such research, however, is key to overcoming experimental limitations in humans and essential to build a detailed understanding of the in-vivo consequences of tES that can ultimately lead to development of targeted and effective therapeutic applications of noninvasive brain stimulation. The sheer difference in scale and geometry between animal models and the human brain contributes to the complexity of designing and interpreting animal studies. Here we extend previous approaches to model intracranial electric fields to generate predictions that can be tested with in-vivo intracranial recordings. Although the toolbox has general applicability and could be used to predict intracranial fields for any tES study using mice, we illustrate its usage by comparing fields in a high-density multi-electrode montage with a more traditional two electrode montage. Our simulations show that both montages can produce strong focal homogeneous electric fields in targeted areas. However, the high-density montage produces a field that is more perpendicular to the visual cortical surface, which is expected to result in larger changes in neuronal excitability.

RESUMEN

Studies aimed at preventing age-associated diseases are fundamental in addressing the challenges posed by an aging population. However, biomedical and technological advancements have now reached a stage where it appears increasingly possible to repair the damage caused by severe pathologies and reverse the functional decline that accompanies aging. This perspective highlights the significance of using aging models, specifically non-transgenic geriatric mice (aged over 24 months), to study interventions aimed at reversing or ameliorating age-related pathologies. While most research typically utilizes young, adult, and mid-aged mice to investigate aging mechanisms and develop preventive strategies, geriatric models provide unique insights into the efficacy and safety of treatments in conditions that mimic the complexities of multiple concurrent diseases or syndromes. This manuscript highlights the importance of considering timing responses in aging interventions, illustrated by recent findings such as those involving canagliflozin. These studies reveal that the timing of intervention can significantly influence the outcomes, highlighting aspects often overlooked. Practical challenges and resource demands associated with geriatric mouse studies including concerns related to animal husbandry and aging phenotypes are also discussed. This perspective aims to foster a deeper understanding of the potential benefits and limitations of geriatric mice models in geroscience research and emphasizes the need for continued innovation in this field to meet the critical need to develop effective treatments for age-related diseases.

RESUMEN

As the eponymous mediators of the cytokine storm syndrome, cytokines are a pleomorphic and diverse set of soluble molecules that activate or suppress immune functions in a wide variety of ways. The relevant cytokines for each CSS are likely a result of differing combinations of environmental triggers and host susceptibilities. Because cytokines or their receptors may be specifically targeted by biologic therapeutics, understanding which cytokines are relevant for disease initiation and propagation for each unique CSS is of major clinical importance. This chapter will review what is known about the role of cytokines across the spectrum of CSS.

Asunto(s)

RESUMEN

Hemophagocytic lymphohistiocytosis (HLH) comprises a broad spectrum of life-threatening cytokine storm syndromes, classified into primary (genetic) or secondary (acquired) HLH. The latter occurs in a variety of medical conditions, including infections, malignancies, autoimmune and autoinflammatory diseases, acquired immunodeficiency, and metabolic disorders. Despite recent advances in the field, the pathogenesis of secondary HLH remains incompletely understood. Considering the heterogeneity of triggering factors and underlying diseases in secondary HLH, a large diversity of animal models has been developed to explore pivotal disease mechanisms. To date, over 20 animal models have been described that each recapitulates certain aspects of secondary HLH. This review provides a comprehensive overview of the existing models, highlighting relevant findings, discussing the involvement of different cell types and cytokines in disease development and progression, and considering points of interest toward future therapeutic strategies.

Asunto(s)

RESUMEN

Introduction: Vitiligo is an acquired skin pigmentation disorder, the cause of which is poorly understood. Researchers in this field are dedicated to exploring novel treatments for achieving re-pigmentation. Methods: Mice were randomly selected and divided into control, model, and model+laser groups. Evaluate the impact of different levels of carbon dioxide laser irradiation on tyrosinase activity, melanocyte viability, and melanin content. Results: In this study, it was found that the cell viability and melanin content were significantly enhanced in human melanocytes after treatment with different energy densities of fractional carbon dioxide laser. In addition, laser-treated vitiligo mouse models showed mild pathological changes. Discussion: Therefore, we believe that fractional carbon dioxide laser may be a potential adjunctive modality for treating vitiligo.

RESUMEN

Gaucher disease (GD) is caused by biallelic GBA1/Gba1 mutations that encode defective glucocerebrosidase (GCase). Progranulin (PGRN, encoded by GRN/Grn) is a modifier of GCase, but the interplay between PGRN and GCase, specifically GBA1/Gba1 mutations, contributing to GD severity is unclear. Mouse models were developed with various dosages of Gba1 D409V mutation against the PGRN deficiency (Grn-/-) [Grn-/-;Gba1D409V/WT (PG9Vwt), Grn-/-;Gba1D409V/D409V (PG9V), Grn-/-;Gba1D409V/Null (PG9VN)]. Disease progression in those mouse models was characterized by biochemical, pathological, transcriptomic, and neurobehavioral analyses. Compared to PG9Vwt, Grn-/-;Gba1WT/Null and Grn-/- mice that had a higher level of GCase activity and undetectable pathologies, homozygous or hemizygous D409V in PG9V or PG9VN, respectively, resulted in profound inflammation and neurodegeneration. PG9VN mice exhibited much earlier onset, shorter life span, tissue fibrosis, and more severe phenotypes than PG9V mice. Glycosphingolipid accumulation, inflammatory responses, lysosomal-autophagy dysfunction, microgliosis, retinal gliosis, as well as α-Synuclein increases were much more pronounced in PG9VN mice. Neurodegeneration in PG9VN was characterized by activated microglial phagocytosis of impaired neurons and programmed cell death due to necrosis and, possibly, pyroptosis. Brain transcriptomic analyses revealed the intrinsic relationship between D409V dosage, and the degree of altered gene expression related to lysosome dysfunction, microgliosis, and neurodegeneration in GD, suggesting the disease severity is dependent on a GCase activity threshold related to Gba1 D409V dosage and loss of PGRN. These findings contribute to a deeper understanding of GD pathogenesis by elucidating additional underlying mechanisms of interplay between PGRN and Gba1 mutation dosage in modulating GCase function and disease severity in GD and GBA1-associated neurodegenerative diseases.

RESUMEN

T cells express an enormous repertoire of T cell receptors, enabling them to recognize any potential antigen. This large repertoire undergoes stringent selections in the thymus, where receptors that react to self- or non-danger-associated- antigens are purged. We know that thymic tolerance depends on signals and antigens presented by the thymic antigen presenting cells, but we still do not understand precisely how many of these cells actually contribute to tolerance. This is especially true for thymic dendritic cells (DC), which are composed of diverse subpopulations that are derived from different progenitors. Although the importance of thymic DCs has long been known, the functions of specific DC subsets have been difficult to untangle. There remains insufficient systematic characterization of the ontogeny and phenotype of thymic APCs in general. As a result, validated experimental models for studying thymic DCs are limited. Recent technological advancement, such as multi-omics analyses, has enabled new insights into thymic DC biology. These recent findings indicate a need to re-evaluate the current tools used to study the function of these cells within the thymus. This review will discuss how thymic DC subpopulations can be defined, the models that have been used to assess functions in the thymus, and models developed for other settings that can be potentially used for studying thymic DCs.

Asunto(s)

RESUMEN

Our study was to characterize sarcopenia in C57BL/6J mice using a clinically relevant definition to investigate the underlying molecular mechanisms. Aged male (23-32 months old) and female (27-28 months old) C57BL/6J mice were classified as non-, probable-, or sarcopenic based on assessments of grip strength, muscle mass, and treadmill running time, using 2 SDs below the mean of their young counterparts as cutoff points. A 9%-22% prevalence of sarcopenia was identified in 23-26 month-old male mice, with more severe age-related declines in muscle function than mass. Females aged 27-28 months showed fewer sarcopenic but more probable cases compared with the males. As sarcopenia progressed, a decrease in muscle contractility and a trend toward lower type IIB fiber size were observed in males. Mitochondrial biogenesis, oxidative capacity, and AMPK-autophagy signaling decreased as sarcopenia progressed in males, with pathways linked to mitochondrial metabolism positively correlated with muscle mass. No age- or sarcopenia-related changes were observed in mitochondrial biogenesis, OXPHOS complexes, AMPK signaling, mitophagy, or atrogenes in females. Our results highlight the different trajectories of age-related declines in muscle mass and function, providing insights into sex-dependent molecular changes associated with sarcopenia progression, which may inform the future development of novel therapeutic interventions.

Asunto(s)