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1.
Cell Immunol ; 399-400: 104825, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38648700

RESUMO

Macrophage niches are the anatomical locations within organs or tissues consisting of various cells, intercellular and extracellular matrix, transcription factors, and signaling molecules that interact to influence macrophage self-maintenance, phenotype, and behavior. The niche, besides physically supporting macrophages, imposes a tissue- and organ-specific identity on the residing and infiltrating monocytes and macrophages. In this review, we give examples of macrophage niches and the modes of communication between macrophages and surrounding cells. We also describe how macrophages, acting against their immune defensive nature, can create a hospitable niche for pathogens and cancer cells.

2.
Cell Tissue Res ; 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38625373

RESUMO

Gadolinium is a component of the MRI contrast agent Dotarem. Although Dotarem is the least toxic among MRI contrasts used, gadolinium present in Dotarem accumulates for many years in various organs and tissues exerting toxic effects. We showed previously that gadolinium remains in macrophages for at least 7 days after exposure to Dotarem. However, very little is known about the effect of gadolinium retention on the immune cells such as macrophages. We studied the effect of 1-day and 7-day retention of gadolinium on various functions and molecular pathways of macrophages. Gadolinium retention for 7 days decreased macrophage adhesion and motility and dysregulated the expression of adhesion and fibrotic pathway-related proteins such as Notch1 and its ligand Jagged1, adhesion/migration-related proteins PAK1 and Shp1, immune response-related transcription factors Smad3 and TCF19, and chemokines CXCL10 and CXCL13, and dysregulated the mRNA expression of fibrosis-related genes involved in extracellular matrix (ECM) synthesis, such as Col6a1, Fibronectin, MMP9, and MMP12. It also completely (below a level of detection) shut down the transcription of anti-inflammatory M2 macrophage polarization marker the Arg-1. Such changes, if they occur in MRI patients, can be potentially detrimental to the patient's immune system and immune response-related processes.

3.
Nat Immunol ; 25(1): 66-76, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38168955

RESUMO

CD4+ T cells are central to various immune responses, but the molecular programs that drive and maintain CD4+ T cell immunity are not entirely clear. Here we identify a stem-like program that governs the CD4+ T cell response in transplantation models. Single-cell-transcriptomic analysis revealed that naive alloantigen-specific CD4+ T cells develop into TCF1hi effector precursor (TEP) cells and TCF1-CXCR6+ effectors in transplant recipients. The TCF1-CXCR6+CD4+ effectors lose proliferation capacity and do not reject allografts upon adoptive transfer into secondary hosts. By contrast, the TCF1hiCD4+ TEP cells have dual features of self-renewal and effector differentiation potential, and allograft rejection depends on continuous replenishment of TCF1-CXCR6+ effectors from TCF1hiCD4+ TEP cells. Mechanistically, TCF1 sustains the CD4+ TEP cell population, whereas the transcription factor IRF4 and the glycolytic enzyme LDHA govern the effector differentiation potential of CD4+ TEP cells. Deletion of IRF4 or LDHA in T cells induces transplant acceptance. These findings unravel a stem-like program that controls the self-renewal capacity and effector differentiation potential of CD4+ TEP cells and have implications for T cell-related immunotherapies.


Assuntos
Regulação da Expressão Gênica , Linfócitos T Reguladores , Diferenciação Celular
4.
Int J Mol Sci ; 25(2)2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38256145

RESUMO

While the vertebrate immune system consists of innate and adaptive branches, invertebrates only have innate immunity. This feature makes them an ideal model system for studying the cellular and molecular mechanisms of innate immunity sensu stricto without reciprocal interferences from adaptive immunity. Although invertebrate immunity is evolutionarily older and a precursor of vertebrate immunity, it is far from simple. Despite lacking lymphocytes and functional immunoglobulin, the invertebrate immune system has many sophisticated mechanisms and features, such as long-term immune memory, which, for decades, have been exclusively attributed to adaptive immunity. In this review, we describe the cellular and molecular aspects of invertebrate immunity, including the epigenetic foundation of innate memory, the transgenerational inheritance of immunity, genetic immunity against invading transposons, the mechanisms of self-recognition, natural transplantation, and germ/somatic cell parasitism.


Assuntos
Células Germinativas , Imunidade Inata , Animais , Invertebrados , Imunidade Adaptativa , Comunicação Celular
5.
Stem Cell Investig ; 10: 9, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37077316

RESUMO

Like all immune cells, macrophages do not act autonomously but in unison with other immune cells, surrounding tissues, and the niche they occupy. Constant exchange of information between cellular and noncellular participants within a tissue allows for preserving homeostasis and defining responses in a pathologic environment. Although molecular mechanisms and pathways involved in reciprocal signaling between macrophages and other immune cells have been known for decades, much less is known about interactions between macrophages and stem/progenitor cells. Based on the time when stem cells form, there are two stem cell types: embryonic stem cells existing only in an early embryo, which are pluripotent and can differentiate into any cell type present in an adult, and somatic (adult) stem cells formed in fetus and persisting for whole adult life. Tissues and organs have their own (tissue-specific and organ-specific) adult stem cells, which serve as a reserve for tissue homeostasis and regeneration after injury. It is still uncertain whether organ- and tissue-specific stem cells are actual stem cells or just progenitor cells. The important question is how stem/progenitor cells can sculpt macrophage phenotype and functions. Even less is known if or how macrophages can shape stem/progenitor cell functions, their divisions, and fate. We describe here examples from recent studies of how stem/progenitor cells can affect macrophages and how macrophages can influence stem/progenitor cell properties, functions, and destiny.

6.
Int Immunopharmacol ; 118: 110017, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36931169

RESUMO

Macrophages play a crucial role in, the currently uncurable, chronic rejection of transplants. In rodent transplantation models, inhibition of the RhoA/Rock pathway disrupts actin-related functions of macrophages, preventing them from entering the graft, and reducing vessel occlusion, fibrosis, and chronic rejection. Among RhoA/Rock inhibitors that inhibit chronic rejection in mouse transplantation are Y27632, Fingolimod, and Rezurock. In a mouse model, Rezurok is more effective in preventing fibrosis and less effective in preventing vessel occlusion than Y27632 or Fingolimod. Fingolimod is FDA-approved for treating multiple sclerosis (MS) and Rezurock for chronic graft versus host disease (GVHD). Still, none had been tested for chronic rejection in humans. To explain the differences in the anti-chronic rejection properties of Y27632, Fingolimod, and Rezurock, we compared the transcriptome profile of mouse macrophages treated with these compounds separately. Treatment with Y27632 or Fingolimod downregulated GTPase and actin pathways involved in cell migration. Rezurock downregulated genes related to fibrosis, such as PTX3, CCR2, CCL2, cell cycle, DNA replication, adaptive immune response, and organelle assembly, while Fingolimod also specifically downregulated NOTCH1 at mRNA . The result of this study not only uncovers which pathways are shared or specific for these drugs but will help in the development of macrophage pathway-targeted therapies in human transplantation, MS, and GVHD. Because macrophages are the major players in immune response, tissue regeneration, renewal, and homeostasis, and development of many diseases, including cancer, the data compiled here will help in designing novel or improved therapies in many clinical applications.


Assuntos
Cloridrato de Fingolimode , Doença Enxerto-Hospedeiro , Animais , Humanos , Camundongos , Actinas/metabolismo , Fibrose , Cloridrato de Fingolimode/farmacologia , Cloridrato de Fingolimode/uso terapêutico , Macrófagos , Quinases Associadas a rho/genética , Quinases Associadas a rho/metabolismo , Proteína rhoA de Ligação ao GTP/metabolismo , Transcriptoma
7.
Cancers (Basel) ; 15(5)2023 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-36900226

RESUMO

The rationale for administering immune checkpoint inhibitors (ICIs) in the adjuvant setting is to eradicate micro-metastases and, ultimately, prolong survival. Thus far, clinical trials have demonstrated that 1-year adjuvant courses of ICIs reduce the risk of recurrence in melanoma, urothelial cancer, renal cell carcinoma, non-small cell lung cancer, and esophageal and gastroesophageal junction cancers. Overall survival benefit has been shown in melanoma while survival data are still not mature in other malignancies. Emerging data also show the feasibility of utilizing ICIs in the peri-transplant setting for hepatobiliary malignancies. While ICIs are generally well-tolerated, the development of chronic immune-related adverse events, typically endocrinopathies or neurotoxicities, as well as delayed immune-related adverse events, warrants further scrutiny regarding the optimal duration of adjuvant therapy and requires a thorough risk-benefit determination. The advent of blood-based, dynamic biomarkers such as circulating tumor DNA (ctDNA) can help detect minimal residual disease and identify the subset of patients who would likely benefit from adjuvant treatment. In addition, the characterization of tumor-infiltrating lymphocytes, neutrophil-to-lymphocyte ratio, and ctDNA-adjusted blood tumor mutation burden (bTMB) has also shown promise in predicting response to immunotherapy. Until additional, prospective studies delineate the magnitude of overall survival benefit and validate the use of predictive biomarkers, a tailored, patient-centered approach to adjuvant ICIs that includes extensive patient counseling on potentially irreversible adverse effects should be routinely incorporated into clinical practice.

8.
Liver Transpl ; 29(1): 34-47, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36630156

RESUMO

NAFLD will soon be the most common indication for liver transplantation (LT). In NAFLD, HCC may occur at earlier stages of fibrosis and present with more advanced tumor stage, raising concern for aggressive disease. Thus, adult LT recipients with HCC from 20 US centers transplanted between 2002 and 2013 were analyzed to determine whether NAFLD impacts recurrence-free post-LT survival. Five hundred and thirty-eight (10.8%) of 4981 total patients had NAFLD. Patients with NAFLD were significantly older (63 vs. 58, p<0.001), had higher body mass index (30.5 vs. 27.4, p<0.001), and were more likely to have diabetes (57.3% vs. 28.8%, p<0.001). Patients with NAFLD were less likely to receive pre-LT locoregional therapy (63.6% vs. 72.9%, p<0.001), had higher median lab MELD (15 vs. 13, p<0.001) and neutrophil-lymphocyte ratio (3.8 vs. 2.9, p<0.001), and were more likely to have their maximum pre-LT alpha fetoprotein at time of LT (44.1% vs. 36.1%, p<0.001). NAFLD patients were more likely to have an incidental HCC on explant (19.4% vs. 10.4%, p<0.001); however, explant characteristics including tumor differentiation and vascular invasion were not different between groups. Comparing NAFLD and non-NAFLD patients, the 1, 3, and 5-year cumulative incidence of recurrence (3.1%, 9.1%, 11.5% vs. 4.9%, 10.1%, 12.6%, p=0.36) and recurrence-free survival rates (87%, 76%, and 67% vs. 87%, 75%, and 67%, p=0.97) were not different. In competing risks analysis, NAFLD did not significantly impact recurrence in univariable (HR: 0.88, p=0.36) nor in adjusted analysis (HR: 0.91, p=0.49). With NAFLD among the most common causes of HCC and poised to become the leading indication for LT, a better understanding of disease-specific models to predict recurrence is needed. In this NAFLD cohort, incidental HCCs were common, raising concerns about early detection. However, despite less locoregional therapy and high neutrophil-lymphocyte ratio, explant tumor characteristics and post-transplant recurrence-free survival were not different compared to non-NAFLD patients.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Transplante de Fígado , Hepatopatia Gordurosa não Alcoólica , Adulto , Humanos , Carcinoma Hepatocelular/epidemiologia , Carcinoma Hepatocelular/cirurgia , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/cirurgia , Neoplasias Hepáticas/patologia , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Hepatopatia Gordurosa não Alcoólica/cirurgia , Transplante de Fígado/efeitos adversos , Estudos Retrospectivos , Recidiva Local de Neoplasia/patologia , Fatores de Risco
9.
Int J Mol Sci ; 23(22)2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36430636

RESUMO

Atherosclerosis is an inflammatory disease depending on the buildup, called plaque, of lipoproteins, cholesterol, extracellular matrix elements, and various types of immune and non-immune cells on the artery walls. Plaque development and growth lead to the narrowing of the blood vessel lumen, blocking blood flow, and eventually may lead to plaque burst and a blood clot. The prominent cellular components of atherosclerotic plaque are the foam cells, which, by trying to remove lipoprotein and cholesterol surplus, also participate in plaque development and rupture. Although the common knowledge is that the foam cells derive from macrophages, studies of the last decade clearly showed that macrophages are not the only cells able to form foam cells in atherosclerotic plaque. These findings give a new perspective on atherosclerotic plaque formation and composition and define new targets for anti-foam cell therapies for atherosclerosis prevention. This review gives a concise description of foam cells of different pedigrees and describes the main mechanisms participating in their formation and function.


Assuntos
Aterosclerose , Placa Aterosclerótica , Humanos , Macrófagos/fisiologia , Colesterol , Músculo Liso Vascular , Células-Tronco , Endotélio
10.
JCI Insight ; 7(23)2022 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-36256455

RESUMO

BRD4 is a bromodomain extraterminal domain family member and functions primarily as a chromatin reader regulating genes involved in cell-fate decisions. Here, we bred Brd4fl/fl Ox40-Cre mice in which Brd4 was conditionally deleted in OX40-expressing cells to examine the role of BRD4 in regulating immune responses. We found that the Brd4fl/fl Ox40-Cre mice developed profound alopecia and dermatitis, while other organs and tissues were not affected. Surprisingly, lineage-tracing experiments using the Rosa26fl/fl-Yfp mice identified a subset of hair follicle stem cells (HFSCs) that constitutively express OX40, and deletion of Brd4 specifically in such HFSCs resulted in cell death and a complete loss of skin hair growth. We also found that death of HFSCs triggered massive activation of the intradermal γδ T cells, which induced epidermal hyperplasia and dermatitis by producing the inflammatory cytokine IL-17. Interestingly, deletion of Brd4 in Foxp3+ Tregs, which also constitutively express OX40, compromised their suppressive functions, and this, in turn, contributed to the enhanced activation of γδ T cells, as well as the severity of dermatitis and hair follicle destruction. Thus, our data demonstrate an unexpected role of BRD4 in regulating skin follicle stem cells and skin inflammation.


Assuntos
Alopecia , Folículo Piloso , Proteínas Nucleares , Fatores de Transcrição , Animais , Camundongos , Alopecia/genética , Dermatite , Proteínas Nucleares/genética , Células-Tronco , Fatores de Transcrição/genética
11.
Biology (Basel) ; 11(8)2022 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-35892977

RESUMO

This review introduces the subject of senescence, aging, and the formation of senescent multinucleated giant cells. We define senescence and aging and describe how molecular and cellular senescence leads to organismal senescence. We review the latest information on senescent cells' cellular and molecular phenotypes. We describe molecular and cellular features of aging and senescence and the role of multinucleated giant cells in aging-related conditions and cancer. We explain how multinucleated giant cells form and their role in aging arteries and gonads. We also describe how multinucleated giant cells and the reversibility of senescence initiate cancer and lead to cancer progression and metastasis. We also describe molecules and pathways regulating aging and senescence in model systems and their applicability to clinical therapies in age-related diseases.

12.
Curr Oncol ; 29(6): 4267-4273, 2022 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-35735450

RESUMO

Systemic combination therapy of immune checkpoint inhibitors and vascular endothelial growth factors have provided the basis for improved outcomes in select patients with unresectable or metastatic hepatocellular carcinoma. However, for patients with resectable disease, surgery alone or an orthotopic liver transplant remains the standard of care. Within the realms of transplant oncology, neoadjuvant systemic therapy is currently being evaluated as a potential strategy to improve outcomes in patients with HCC. Here, we report excellent response with significant downstaging in a safe manner after neoadjuvant treatment with atezolizumab and bevacizumab in a patient diagnosed with poorly differentiated HCC. As a result of the significant response observed with safe outcomes, the patient was listed for orthotopic liver transplant (OLT) evaluation and transplanted successfully.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Transplante de Fígado , Dor Abdominal/etiologia , Idoso , Carcinoma Hepatocelular/tratamento farmacológico , Humanos , Imunoterapia , Neoplasias Hepáticas/tratamento farmacológico , Transplante de Fígado/efeitos adversos , Masculino , Terapia Neoadjuvante
13.
Front Oncol ; 12: 908687, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35719974

RESUMO

Background: Cholangiocarcinoma management is constantly being updated in view of existing evidence in order to establish practice guidelines and consensus statements. However, the available treatment guidelines to optimize outcomes for cholangiocarcinoma patients who require liver transplantation are still controversial. This study contributing to the cholangiocarcinoma care field by investigating a new promising neoadjuvant therapy that might be help to grant the liver transplant option to the patients with cholangiocarcinoma. Here, we evaluate and compare the potential efficacy of chemotherapy combination of Gemcitabine plus Cisplatin versus non- Gemcitabine and Cisplatin regimens as a neo-adjuvant treatment for cholangiocarcinoma patients prior to liver transplantation. Methods: In this retrospective study, patients with locally advanced, unresectable, hilar, or intrahepatic cholangiocarcinoma with no evidence of extrahepatic disease or vascular involvement were treated with either the combination of neo-adjuvant Gemcitabine plus Cisplatin with no radiation or other standard options of neo-adjuvant treatment. All patients included received chemotherapy prior to being listed for liver transplantation at a single cancer center in collaboration with the same institution's transplant center according to an open-labeled, and centers-approved clinical management protocol. Patients were listed for liver transplantation if they had a minimum of six months of scans showing response or confirmation of disease stability. The primary endpoints were the overall survival and recurrence-free survival after liver transplantation. This report, which was censored on March 18, 2022. Results: Out of a total of 707 liver transplant recipients were screened, 37 patients were confirmed with a diagnosis of cholangiocarcinoma and only 18 patients (11 males and 7 females) with a median age of 61.83 [interquartile range: 58.27-68.74] met inclusion criteria. Of the 18 patients enrolled, 10 received Gemcitabine/Cisplatin, while 8 patients received either Gemcitabine monotherapy or Capecitabine or FOLFIRI. Months for recurrence after transplantation was 20.1 (IRQ: 20.1-20.1) in the Gemcitabine/Cisplatin group and 9.5 (8.9-12.47) months in the non-Gemcitabine/Cisplatin group (p-value=0.18). Median months of follow-up in the Gemcitabine/Cisplatin group was 28.35 (27.1-32.23) months versus 40.12 (20.6-56.22) months in the non-Gemcitabine/Cisplatin group (p-value=0.33). In non-Gemcitabine/Cisplatin patients, overall survival was 75% (95% CI 31-93%) at both years 1 and 2; 63% (95% CI 23-86%) at years 3 to 5. In Gemcitabine/Cisplatin patients, overall survival was 100% (95% CI 100-100%) at both years 1 and 2; 75% (95% CI 13-96%) at years 3 to 5. Three non-Gemcitabine/Cisplatin patients died at 328 days, 340 days, and 896 days, respectively. One Gemcitabine/Cisplatin patient died at 885 days. Conclusion: Our findings suggest improved overall survival outcomes with Gemcitabine plus Cisplatin as neo-adjuvant treatment with no concomitant radiation compared to non-Gemcitabine/Cisplatin regimens in patients with cholangiocarcinoma prior to liver transplantation.

14.
Int J Mol Sci ; 23(12)2022 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-35742997

RESUMO

Cell fusion (fusogenesis) occurs in natural and pathological conditions in prokaryotes and eukaryotes. Cells of monocyte-macrophage lineage are highly fusogenic. They create syncytial multinucleated giant cells (MGCs) such as osteoclasts (OCs), MGCs associated with the areas of infection/inflammation, and foreign body-induced giant cells (FBGCs). The fusion of monocytes/macrophages with tumor cells may promote cancer metastasis. We describe types and examples of monocyte-macrophage lineage cell fusion and the role of actin-based structures in cell fusion.


Assuntos
Células Gigantes de Corpo Estranho , Monócitos , Diferenciação Celular , Fusão Celular , Células Gigantes/patologia , Células Gigantes de Corpo Estranho/metabolismo , Células Gigantes de Corpo Estranho/patologia , Monócitos/metabolismo , Osteoclastos/metabolismo
15.
Curr Oncol ; 29(5): 3585-3594, 2022 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-35621680

RESUMO

BACKGROUND: The management of cholangiocarcinoma is continually reviewed on a current evidence basis to develop practice guidelines and consensus statements. However, the standardized treatment guidelines are still unclear for cholangiocarcinoma patients who are listed for liver transplantation. We aimed to validate and evaluate the potential efficacy of chemotherapy combination of Gemcitabine and Cisplatin as a neo-adjuvant treatment for cholangiocarcinoma patients before liver transplantation. METHODS: In this prospective case series, patients with locally advanced, unresectable, hilar, or intrahepatic cholangiocarcinoma with no evidence of extrahepatic disease or vascular involvement were treated with a combination of neoadjuvant gemcitabine and cisplatin with no radiation. All patients included received chemotherapy prior to being listed for liver transplantation at a single cancer center according to an open-labeled, and center-approved clinical management protocol. The primary endpoints were the overall survival and recurrence-free survival after liver transplantation. RESULTS: Between 1 March 2016, and 15 March 2022, 10 patients (8 males and 2 females) with a median age of 62.71(interquartile range: 60.02-71.87) had a confirmed diagnosis of intrahepatic or hilar cholangiocarcinoma and underwent liver transplantation. Median days of neoadjuvant therapy for a given combination of gemcitabine and cisplatin were 181 (IRQ: 120-250). Nine patients (90%) were reported with no recurrence or metastasis, and only 1 patient had confirmed metastasis (10%); days for metastasis after transplantation were 612 for this patient. All patients received a combination of gemcitabine and cisplatin as neo-adjuvant while awaiting liver transplantation. The median days of follow-up were 851 (813-967). Overall survival was 100% (95% CI 100-100%) at both years one and two; 75% (95% CI 13-96%) at years three to five. One patient died at eight hundred and eighty-five days. No adverse events were reported after liver transplantation including the patient who was confirmed with recurrence. CONCLUSIONS: Our finding demonstrated that neo-adjuvant gemcitabine and cisplatin with no radiation prior to liver transplantation resulted in excellent outcomes for patients with cholangiocarcinoma.


Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Transplante de Fígado , Neoplasias dos Ductos Biliares/tratamento farmacológico , Neoplasias dos Ductos Biliares/cirurgia , Ductos Biliares Intra-Hepáticos/patologia , Colangiocarcinoma/diagnóstico , Colangiocarcinoma/tratamento farmacológico , Colangiocarcinoma/cirurgia , Cisplatino/uso terapêutico , Desoxicitidina/análogos & derivados , Feminino , Humanos , Masculino , Terapia Neoadjuvante , Gencitabina
16.
Cell Mol Immunol ; 19(6): 687-701, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35322175

RESUMO

The RNA helicase DHX15 is widely expressed in immune cells and traditionally thought to be an RNA splicing factor or a viral RNA sensor. However, the role of DHX15 in NK-cell activities has not been studied thus far. Here, we generated Dhx15-floxed mice and found that conditional deletion of Dhx15 in NK cells (Ncr1CreDhx15fl/fl mice) resulted in a marked reduction in NK cells in the periphery and that the remaining Dhx15-deleted NK cells failed to acquire a mature phenotype. As a result, Dhx15-deleted NK cells exhibited profound defects in their cytolytic functions. We also found that deletion of Dhx15 in NK cells abrogated their responsiveness to IL-15, which was associated with inhibition of IL-2/IL-15Rß (CD122) expression and IL-15R signaling. The defects in Dhx15-deleted NK cells were rescued by ectopic expression of a constitutively active form of STAT5. Mechanistically, DHX15 did not affect CD122 mRNA splicing and stability in NK cells but instead facilitated the surface expression of CD122, likely through interaction with its 3'UTR, which was dependent on the ATPase domain of DHX15 rather than its splicing domain. Collectively, our data identify a key role for DHX15 in regulating NK-cell activities and provide novel mechanistic insights into how DHX15 regulates the IL-15 signaling pathway in NK cells.


Assuntos
Interleucina-15 , RNA Helicases , Animais , Homeostase , Células Matadoras Naturais/metabolismo , Camundongos , RNA Helicases/genética , RNA Helicases/metabolismo , Transdução de Sinais
17.
Dev Biol ; 486: 15-25, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35321809

RESUMO

Typically, all cells of a given organism have the same set of chromosomes. However, there are exceptions to this rule, and in many organisms, the somatic cells and germ cells, various types of somatic cells or organs, or females and males, have different genomes. One of the sources of such differences is chromosome/DNA elimination/chromatin diminution that is a naturally programmed phenomenon. We describe chromosome/DNA elimination in various organisms and present the current hypotheses on its origin, mechanisms, significance, and consequences.


Assuntos
Cromatina , Cromossomos , DNA/genética , Feminino , Engenharia Genética , Genoma/genética , Humanos , Masculino
18.
Cells ; 11(5)2022 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-35269379

RESUMO

Magnetic resonance imaging (MRI) is widely used in diagnostic medicine. MRI uses the static magnetic field to polarize nuclei spins, fast-switching magnetic field gradients to generate temporal and spatial resolution, and radiofrequency (RF) electromagnetic waves to control the spin orientation. All these forms of magnetic static and electromagnetic RF fields interact with human tissue and cells. However, reports on the MRI technique's effects on the cells and human body are often inconsistent or contradictory. In both research and clinical MRI, recent progress in improving sensitivity and resolution is associated with the increased magnetic field strength of MRI magnets. Additionally, to improve the contrast of the images, the MRI technique often employs contrast agents, such as gadolinium-based Dotarem, with effects on cells and organs that are still disputable and not fully understood. Application of higher magnetic fields requires revisiting previously observed or potentially possible bio-effects. This article focuses on the influence of a static magnetic field gradient with and without a gadolinium-based MRI contrast agent (Dotarem) and the cellular and molecular effects of Dotarem on macrophages.


Assuntos
Meios de Contraste , Gadolínio , Animais , Gadolínio/farmacologia , Macrófagos , Campos Magnéticos , Imageamento por Ressonância Magnética/métodos , Meglumina , Camundongos , Compostos Organometálicos
19.
Cancers (Basel) ; 14(3)2022 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-35158918

RESUMO

BACKGROUND: Hepatocellular carcinoma (HCC) is the sixth most common malignancy and the third most common cause of cancer-related mortality worldwide. Transarterial chemoembolization has shown survival benefits in patients with early to intermediate-stage HCC, becoming the standard of care and recommended treatment modality by most clinical practice guidelines. The most recent trials of the TACE plus sorafenib combined therapy in patients with unresectable HCC have yielded inconsistent outcomes. The purpose of this study was to compare the outcomes of HCC patients treated with the TACE sorafenib combination as opposed to TACE monotherapy. METHODS: This retrospective study included all patients with unresectable HCC who underwent liver transplantation and were treated by either TACE alone or TACE plus sorafenib between July 2008-December 2019. Demographic and clinical data as well as HCC recurrence post-liver transplant (LT) were reported as frequencies and proportions for categorical variables and as the median and interquartile range (IQR) or mean. Chi-square or Fisher's exact tests were performed for categorical variables and the Kruskal-Wallis test or unpaired test was performed for continuous variables. Kaplan-Meier curves present overall patient survival and HCC-free survival. RESULTS: A total of 128 patients received LT, with a median (IQR) age of 61.4 (57.0, 66.3) years; most were males (77%). Within the TACE-only group, 79 (77%) patients met the Milan criteria and 24 (23%) were beyond the Milan criteria, while the TACE plus sorafenib group had a higher proportion of patients beyond the Milan criteria: 16 (64%) vs. 9 (36%); p = 0.01. The five-year disease-free survival (DFS) between the treatment groups approached significance, with 100% DFS in the TACE plus sorafenib group vs. 67.2% in the TACE-alone group, p = 0.07. Five-year patient survival was 77.8% in the TACE plus sorafenib group compared to 61.5% in the TACE-alone group (p = 0.51). However, in patients who met the beyond Milan criteria, those who received TACE alone had a lower average amount of (percent) tumor necrosis on explant pathology (43.8% ± 32%) compared to patients who received TACE plus sorafenib (69.6% ± 32.8%, p = 0.03). CONCLUSION: This study identified that using TACE plus sorafenib is generally well-tolerated and demonstrated improved overall survival compared to TACE only in transplant recipients with unresectable HCC. A multi-center and prospective randomized controlled trial is needed to substantiate these findings.

20.
Arch Virol ; 167(3): 737-749, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35102456

RESUMO

The actin cytoskeleton and actin-dependent molecular and cellular events are responsible for the organization of eukaryotic cells and their functions. Viruses, including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), depend on host cell organelles and molecular components for cell entry and propagation. Thus, it is not surprising that they also interact at many levels with the actin cytoskeleton of the host. There have been many studies on how different viruses reconfigure and manipulate the actin cytoskeleton of the host during successive steps of their life cycle. However, we know relatively little about the interactions of SARS-CoV-2 with the actin cytoskeleton. Here, we describe how the actin cytoskeleton is involved in the strategies used by different viruses for entry, assembly, and egress from the host cell. We emphasize what is known and unknown about SARS-CoV-2 in this regard. This review should encourage further investigation of the interactions of SARS-CoV-2 with cellular components, which will eventually be helpful for developing novel antiviral therapies for mitigating the severity of COVID-19.


Assuntos
COVID-19 , Vírus não Classificados , Citoesqueleto de Actina , Antivirais/uso terapêutico , Humanos , SARS-CoV-2
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