scholarly journals Yap/Taz-Activated Tert-Expressing Acinar Cells Are Required for Pancreatic Regeneration

2021 ◽  
Author(s):  
Han Na Suh ◽  
Moon Jong Kim ◽  
Sung Ho Lee ◽  
Sohee Jun ◽  
Jie Zhang ◽  
...  
Keyword(s):  
Cell Injury ◽  
Acinar Cells ◽  
Genetically Engineered ◽  
Tissue Homeostasis ◽  
Telomerase Reverse Transcriptase ◽  
Subsequent Generation ◽  
Genetic Ablation ◽  
Pancreatic Regeneration ◽  
Distinct Subset ◽  
Stem And Progenitor Cells

ABSTRACTThe expression of TERT (telomerase reverse transcriptase) has been implicated in stem and progenitor cells, which are essential for tissue homeostasis and regeneration. However, the roles of TERT-expressing cells in the pancreas remain elusive. Employing genetically engineered Tert knock-in mouse model, herein, we located a rare population of Tert+ acinar cells. While Tert+ cells are quiescent in normal conditions, acinar cell injury leads to mitotic activation of Tert+ cells and subsequent generation of new acinar cells. Moreover, the genetic ablation of Tert+ cells impairs pancreatic regeneration. We further found that Yap/Taz activation is required for the expansion of Tert+ acinar cells. Our results identified Tert+ acinar cells as a distinct subset of acinar cells, which contributes to pancreatic regeneration via Yap/Taz activation.

TNF-α Suppresses Autophagic Flux in Acinar Cells in IgG4-Related Sialadenitis

2019 ◽  
Vol 98 (12) ◽  
pp. 1386-1396 ◽  
Author(s):  
X. Hong ◽  
S.N. Min ◽  
Y.Y. Zhang ◽  
Y.T. Lin ◽  
F. Wang ◽  
...  
Keyword(s):  
Acinar Cell ◽  
Cell Injury ◽  
Ex Vivo ◽  
Secretory Granules ◽  
Acinar Cells ◽  
Autophagic Flux ◽  
C6 Cells ◽  
Tnf Α ◽  
Α Level

IgG4-related sialadenitis (IgG4-RS) is a newly recognized immune-mediated systemic fibroinflammatory disease that affects salivary glands and leads to hyposalivation. Tumor necrosis factor–α (TNF-α) is a critical proinflammatory cytokine involved in several salivary gland disorders, but its role and mechanism regarding acinar cell injury in IgG4-RS are unknown. Here, we found that TNF-α level was significantly increased in serum and submandibular gland (SMG) of patients and that serum TNF-α level was negatively correlated with saliva flow rate. Ultrastructural observations of IgG4-RS SMGs revealed accumulation of large autophagic vacuoles, as well as dense fibrous bundles, decreased secretory granules, widened intercellular spaces, swollen mitochondria, and expanded endoplasmic reticulum. Expression levels of LC3 and p62 were both increased in patients’ SMGs. TNF-α treatment led to elevated levels of LC3II and p62 in both SMG-C6 cells and cultured human SMG tissues but did not further increase their levels when combined with bafilomycin A1 treatment. Moreover, transfection of Ad-mCherry-GFP-LC3B in SMG-C6 cells confirmed the suppression of autophagic flux after TNF-α treatment. Immunofluorescence imaging revealed that costaining of LC3 and the lysosomal marker LAMP2 was significantly decreased in patients, TNF-α–treated SMG-C6 cells, and cultured human SMGs, indicating a reduction in autophagosome-lysosome fusion. Furthermore, the ratio of pro/mature cathepsin D was elevated in vivo, ex vivo, and in vitro. TNF-α also appeared to induce abnormal acidification of lysosomes in acinar cells, as assessed by lysosomal pH and LysoTracker DND-26 fluorescence intensity. In addition, TNF-α treatment induced transcription factor EB (TFEB) redistribution in SMG-C6 cells, which was consistent with the changes observed in IgG4-RS patients. TNF-α increased the phosphorylation of extracellular signal–regulated kinase (ERK) 1/2, and inhibition of ERK1/2 by U0126 reversed TNF-α–induced TFEB redistribution, lysosomal dysfunction, and autophagic flux suppression. These findings suggest that TNF-α is a key cytokine related to acinar cell injury in IgG4-RS through ERK1/2-mediated autophagic flux suppression.

Effect of oxidative stress on cellular functions and cytosolic free calcium of rat pancreatic acinar cells

1997 ◽  
Vol 272 (6) ◽  
pp. G1489-G1498 ◽  
Author(s):  
H. Klonowski-Stumpe ◽  
R. Schreiber ◽  
M. Grolik ◽  
H. U. Schulz ◽  
D. Haussinger ◽  
...  
Keyword(s):  
Cell Injury ◽  
Cell Damage ◽  
Acinar Cells ◽  
Pancreatic Acinar Cell ◽  
Pancreatic Acinar Cells ◽  
Free Calcium ◽  
Cellular Functions ◽  
Cytosolic Free Calcium ◽  
Catalyzed Oxidation ◽  
Sustained Increase

The present study evaluates the effect of free radicals generated by xanthine oxidase-catalyzed oxidation of hypoxanthine on cellular function of isolated rat pancreatic acinar cells. The results show that a rapid and sustained increase in intracellular Ca2+ concentration ([Ca2+]i) preceded all other morphological and functional alterations investigated. Radical-induced [Ca2+]i increase was largely inhibited by 3,4,5-trimethoxybenzoic acid 8-(diethylamino)octyl ester, which prevents Ca2+ release from intracellular stores, but not by Ca2(+)-depleted medium. Radicals released Ca2+ from thapsigargin-insensitive, ryanodine-sensitive intracellular stores, whereas the secretagogue caerulein at physiological concentrations mainly released Ca2+ from thapsigargin-sensitive stores. In contrast to effects of the secretagogue, radical-induced Ca2+ changes did not cause luminal protein secretion but cell death. In single-cell measurements, both secretagogue and radicals induced oscillations of [Ca2+]i. Radical-induced oscillations had a lower frequency but similar amplitude when compared with caerulein-induced oscillations. 1,2-Bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid and ryanodine, which prevented the radical-induced Ca2+ increase without altering the generation of radicals, markedly reduced the radical-induced cell damage. These results suggest that the Ca2+ increase mediates the radical-induced cell injury. The studies also indicate that not only the extent and duration but also the origin of [Ca2+]i release as well as the frequency of Ca2+ oscillations may determine whether a pancreatic acinar cell will secrete or die.

TAMI-23. ANTIBODY COCKTAIL IMMUNOTHERAPY FOR GLIOBLASTOMA BY DUAL TARGETING OF IL-6 AND CD40

2021 ◽  
Vol 23 (Supplement_6) ◽  
pp. vi203-vi203
Author(s):  
Fan Yang ◽  
Steven Brem ◽  
Yi Fan
Keyword(s):  
T Cell ◽  
Tumor Regression ◽  
Treatment Resistance ◽  
Genetically Engineered ◽  
Checkpoint Blockade ◽  
Genetic Ablation ◽  
Dual Targeting ◽  
Animal Survival ◽  
Cd40 Expression ◽  
Antibody Cocktail

Abstract Glioblastoma (GBM) is refractory to current T cell-based immunotherapies such as checkpoint blockade. GBM is characterized by extensive infiltration of immunosuppressive macrophages that contribute to the treatment resistance. Here we develop a dual-targeting strategy to synergistically activate tumor-associated macrophages (Mφs), which efficiently overcomes GBM resistance to therapeutic blockade of the PD1 and CTLA4 checkpoints. Consistent with a pro-tumor role of IL-6 in alternative Mφ polarization, we here show that targeting IL-6 by genetic ablation or pharmacological inhibition moderately improves T-cell infiltration into GBM and enhances mouse survival; however, IL-6 inhibition does not synergize PD-1 and CTLA-4 checkpoint blockade. Interestingly, anti-IL-6 therapy reduces CD40 expression in GBM-associated Mφs. We identify a Stat3/HIF-1α-mediated axis, through which IL-6 executes an anti-tumor role to induce CD40 expression in Mφs. Combination of IL-6 inhibition with CD40 stimulation reverses Mφ-mediated tumor immunosuppression, sensitizes tumors to checkpoint blockade, and extends animal survival in two syngeneic GBM models. Notably, this antibody cocktail-based combination immunotherapy with checkpoint blockade almost doubles animal survival in the genetically engineered mouse GBM model and induces complete tumor regression in the GL261 model. Thus, antibody cocktail-based immunotherapy that combines checkpoint blockade with dual-targeting of IL-6 and CD40 may offer exciting therapeutic opportunities for GBM.

scholarly journals Successful hematopoietic stem cell mobilization and apheresis collection using plerixafor alone in sickle cell patients

2018 ◽  
Vol 2 (19) ◽  
pp. 2505-2512 ◽  
Author(s):  
Erica B. Esrick ◽  
John P. Manis ◽  
Heather Daley ◽  
Cristina Baricordi ◽  
Hélène Trébéden-Negre ◽  
...  
Keyword(s):  
Sickle Cell ◽  
Standard Dose ◽  
Genetically Engineered ◽  
Hematopoietic Stem ◽  
Cell Counts ◽  
Cd34 Cells ◽  
Stem And Progenitor Cells ◽  
Hematopoietic Stem Cell Mobilization ◽  
Cell Mobilization ◽  
Single Standard

Abstract Novel therapies for sickle cell disease (SCD) based on genetically engineered autologous hematopoietic stem and progenitor cells (HSPCs) are critically dependent on a safe and effective strategy for cell procurement. We sought to assess the safety and efficacy of plerixafor when used in transfused patients with SCD for HSC mobilization. Six adult patients with SCD were recruited to receive a single dose of plerixafor, tested at lower than standard (180 µg/kg) and standard (240 µg/kg) doses, followed by CD34+ cell monitoring in peripheral blood and apheresis collection. The procedures were safe and well-tolerated. Mobilization was successful, with higher peripheral CD34+ cell counts in the standard vs the low-dose group. Among our 6 donors, we improved apheresis cell collection results by using a deep collection interface and starting apheresis within 4 hours after plerixafor administration. In the subjects who received a single standard dose of plerixafor and followed the optimized collection protocol, yields of up to 24.5 × 106 CD34+ cells/kg were achieved. Interestingly, the collected CD34+ cells were enriched in immunophenotypically defined long-term HSCs and early progenitors. Thus, we demonstrate that plerixafor can be employed safely in patients with SCD to obtain sufficient HSCs for potential use in gene therapy.

scholarly journals Free radicals and the pancreatic acinar cells: role in physiology and pathology

2005 ◽  
Vol 360 (1464) ◽  
pp. 2273-2284 ◽  
Author(s):  
M Chvanov ◽  
O.H Petersen ◽  
A Tepikin
Keyword(s):  
Nitric Oxide ◽  
Signal Transduction ◽  
Acute Pancreatitis ◽  
Vascular Endothelium ◽  
Cell Injury ◽  
Acinar Cells ◽  
Pancreatic Acinar Cells ◽  
Nitrogen Species ◽  
Key Enzyme ◽  
Oxide Synthase

Reactive oxygen and nitrogen species (ROS and RNS) play an important role in signal transduction and cell injury processes. Nitric oxide synthase (NOS)—the key enzyme producing nitric oxide (NO)—is found in neuronal structures, vascular endothelium and, possibly, in acinar and ductal epithelial cells in the pancreas. NO is known to regulate cell homeostasis, and its effects on the acinar cells are reviewed here. ROS are implicated in the early events within the acinar cells, leading to the development of acute pancreatitis. The available data on ROS/RNS involvement in the apoptotic and necrotic death of pancreatic acinar cells will be discussed.

scholarly journals Progenitor-intrinsic Metabolic Sensing Promotes Hematopoietic Homeostasis

2021 ◽  
Author(s):  
Hannah A Pizzato ◽  
Yahui Wang ◽  
Michael Wolfgang ◽  
Brian Finck ◽  
Gary J Patti ◽  
...  
Keyword(s):  
Myeloid Cells ◽  
Cell Loss ◽  
Acid Oxidation ◽  
Hematopoietic Progenitors ◽  
Metabolic Switch ◽  
Genetic Ablation ◽  
Mitochondrial Pyruvate Carrier ◽  
Stem And Progenitor Cells ◽  
Metabolic Sensing ◽  
Extrinsic Feedback

Hematopoietic homeostasis is maintained by stem and progenitor cells in part by extrinsic feedback cues triggered by mature cell loss. We demonstrate a different mechanism by which hematopoietic progenitors intrinsically anticipate and prevent the loss of mature progeny through metabolic switches. We examined hematopoiesis in mice conditionally deficient in long-chain fatty acid oxidation (carnitine palmitoyltransferase 2, Cpt2), glutaminolysis (glutaminase, Gls), or mitochondrial pyruvate import (mitochondrial pyruvate carrier 2, Mpc2). While genetic ablation of Cpt2 or Gls minimally impacted most blood lineages, deletion of Mpc2 led to a sharp decline in mature myeloid cells. However, MPC2-deficient myeloid cells rapidly recovered due to a transient increase in myeloid progenitor proliferation. Competitive bone marrow chimera and stable isotope tracing experiments demonstrated that this proliferative burst was intrinsic to MPC2-deficient progenitors and accompanied by a metabolic switch to glutaminolysis. Thus, hematopoietic progenitors intrinsically adjust to metabolic perturbations independently of feedback from downstream mature cells to maintain homeostasis.

scholarly journals IMMU-11. DUAL TARGETING OF IL-6 AND CD40 OVERCOMES GLIOBLASTOMA RESISTANCE TO IMMUNE CHECKPOINT BLOCKADE

2020 ◽  
Vol 22 (Supplement_2) ◽  
pp. ii107-ii107
Author(s):  
Fan Yang ◽  
Steven Brem ◽  
Yi Fan
Keyword(s):  
T Cell ◽  
Immune Checkpoint Blockade ◽  
Genetically Engineered ◽  
Checkpoint Blockade ◽  
Cell Infiltration ◽  
Genetic Ablation ◽  
T Cell Infiltration ◽  
Dual Targeting ◽  
Animal Survival ◽  
Cd40 Expression

Abstract Glioblastoma (GBM) is refractory to current T cell-based immunotherapies such as checkpoint blockade. GBM is characterized by extensive infiltration of immunosuppressive macrophages (Mφs) that contribute to the treatment resistance. Here we develop a dual-targeting strategy to synergistically activate tumor-associated Mφs, which overcomes GBM resistance to therapeutic blockade of the PD1 and CTLA4 checkpoints. Consistent with a previously established role of IL-6 in alternative Mφ polarization, we show that targeting IL-6 by genetic ablation or pharmacological inhibition moderately improves T cell infiltration and enhances animal survival in a genetically engineered mouse GBM model. However, IL-6 inhibition does not synergize PD-1 and CTLA-4 blockade in GBM. Interestingly, we reveal that anti-IL-6 therapy reduces CD40 expression in GBM-associated Mφs. Our transcriptome analysis identifies a Stat3/HIF-1a-mediated axis, through which IL-6 regulates CD40 expression in Mφs. Finally, we show that combination of IL-6 blockade with CD40 stimulation robustly reverses Mφ-mediated tumor immunosuppression, enhances T cell infiltration, and sensitizes GBM to PD-1 and CTLA-4 blockade treatment, cumulating in inhibited tumor growth and extended animal survival. These findings illustrate a cellular mechanism that regulates Mφ-mediated tumor immunity, and suggest that dual-targeting IL-6 and CD40 may offer exciting opportunities for improving immunotherapy against GBM.

scholarly journals Pancreas-Specific ARID1A Deficiency Promotes Acinar-to-Ductal Metaplasia and Elevates Interleukin-6 Expression in Experimental Pancreatitis Model

2021 ◽  
Author(s):  
Liming Zhang ◽  
Zhaoyun Li ◽  
Yong Zhou ◽  
Jie Zhu ◽  
Chong Jin ◽  
...  
Keyword(s):  
Acute Pancreatitis ◽  
Epigenetic Regulation ◽  
Interleukin 6 ◽  
Ex Vivo ◽  
Acinar Cells ◽  
Genetically Engineered ◽  
Ductal Cells ◽  
Inflammatory Conditions ◽  
Acinar To Ductal Metaplasia

Abstract Background: Although role of ARID1A in pancreatic homeostasis and tumorigenesis has been recently described using genetically engineered mouse (GEM) models, whether ARID1A plays a role in pancreatic inflammation and regeneration remains to be explored.Methods: Pancreas-specific Arid1a-deficient GEM model (Arid1adef) was generated by Ela1-Cre/ERT2 mice crossing with Arid1afl/fl mice and characterized histologically. In physiological and inflammatory conditions, serum amylase and lipase activity were measured to investigate effects of Arid1a deficiency on pancreatic secretion function. Histology analysis of pancreas was used to evaluate pancreatic lesions and recovery. Ex vivo primary acinar cell culture was employed to study acinar-to-ductal metaplasia (ADM) process. In HPNE cells, ARID1A knockdown and histone acetyltransferases inhibitors were used to explore epigenetic regulation on interleukin-6 (IL6) expression. Chromatin immunoprecipitation (ChIP) and quantitative real-time PCR were performed to analyze on IL6 promoters.Results: Arid1a deficiency promoted formation of ductal cysts characterized as silenced acinar genes and activated duct genes. Arid1a-deficient acinar cells were more inclined to trans-differentiation to ductal cells in cerulein-induced acute pancreatitis (AP) model. Expression analysis of proinflammatory cytokines reveals that ARID1A deficiency led to increased IL-6 expression in mice acinar cells and HPNE cells. ARID1A-associated histone acetylation partially involved in epigenetic regulation of IL-6. Conclusion: These results demonstrate ARID1A is involved in cerulein-induced AP development by mediating pro-inflammatory cytokines IL-6 and suggest that ARID1A-containing SWI/SNF complex is an epigenetic regulator of acute pancreatitis.

scholarly journals Pharmacological and genetic inhibition of calcineurin protects against carbachol-induced pathological zymogen activation and acinar cell injury

2012 ◽  
Vol 302 (8) ◽  
pp. G898-G905 ◽  
Author(s):  
Kamaldeen A. Muili ◽  
Mahwish Ahmad ◽  
Abrahim I. Orabi ◽  
Syeda M. Mahmood ◽  
Ahsan U. Shah ◽  
...  
Keyword(s):  
Acinar Cell ◽  
Cell Injury ◽  
Acinar Cells ◽  
High Amplitude ◽  
Pancreatic Acinar Cell ◽  
Critical Event ◽  
Amylase Secretion ◽  
Zymogen Activation ◽  
Inhibitory Peptide ◽  
A Subunit

Acute pancreatitis is a major health burden for which there are currently no targeted therapies. Premature activation of digestive proenzymes, or zymogens, within the pancreatic acinar cell is an early and critical event in this disease. A high-amplitude, sustained rise in acinar cell Ca2+ is required for zymogen activation. We previously showed in a cholecystokinin-induced pancreatitis model that a potential target of this aberrant Ca2+ signaling is the Ca2+-activated phosphatase calcineurin (Cn). However, in this study, we examined the role of Cn on both zymogen activation and injury, in the clinically relevant condition of neurogenic stimulation (by giving the acetylcholine analog carbachol) using three different Cn inhibitors or Cn-deficient acinar cells. In freshly isolated mouse acinar cells, pretreatment with FK506, calcineurin inhibitory peptide (CiP), or cyclosporine (CsA) blocked intra-acinar zymogen activation ( n = 3; P < 0.05). The Cn inhibitors also reduced leakage of lactate dehydrogenase (LDH) by 79%, 62%, and 63%, respectively ( n = 3; P < 0.05). Of the various Cn isoforms, the β-isoform of the catalytic A subunit (CnAβ) was strongly expressed in mouse acinar cells. For this reason, we obtained acinar cells from CnAβ-deficient mice (CnAβ−/−) and observed an 84% and 50% reduction in trypsin and chymotrypsin activation, respectively, compared with wild-type controls ( n = 3; P < 0.05). LDH release in the CnAβ-deficient cells was reduced by 50% ( n = 2; P < 0.05). The CnAβ-deficient cells were also protected against zymogen activation and cell injury induced by the cholecystokinin analog caerulein. Importantly, amylase secretion was generally not affected by either the Cn inhibitors or Cn deficiency. These data provide both pharmacological and genetic evidence that implicates Cn in intra-acinar zymogen activation and cell injury during pancreatitis.

Substance P treatment stimulates chemokine synthesis in pancreatic acinar cells via the activation of NF-κB

2006 ◽  
Vol 291 (6) ◽  
pp. G1113-G1119 ◽  
Author(s):  
Raina Devi Ramnath ◽  
Madhav Bhatia
Keyword(s):  
Acute Pancreatitis ◽  
Substance P ◽  
Acinar Cell ◽  
Cell Injury ◽  
Acinar Cells ◽  
Pancreatic Acinar Cell ◽  
Pancreatic Acinar Cells ◽  
Chemokine Production ◽  
Pancreatic Acini ◽  
Monocyte Chemoattractant Protein 1

Acinar cell injury early in acute pancreatitis leads to a local inflammatory reaction and to the subsequent systemic inflammatory response, which may result in multiple organ dysfunction and death. Inflammatory mediators, including chemokines and substance P (SP), are known to play a crucial role in the pathogenesis of acute pancreatitis. It has been shown that pancreatic acinar cells produce the chemokine monocyte chemoattractant protein-1 (MCP-1) in response to caerulein hyperstimulation, demonstrating that acinar-derived MCP-1 is an early mediator of inflammation in acute pancreatitis. Similarly, SP levels in the pancreas and pancreatic acinar cell expression of neurokinin-1 receptor, the primary receptor for SP, are both increased during secretagogue-induced experimental pancreatitis. This study aims to examine the functional consequences of exposing mouse pancreatic acinar cells to SP and to determine whether it leads to proinflammatory signaling, such as production of chemokines. Exposure of mouse pancreatic acini to SP significantly increased synthesis of MCP-1, macrophage inflammatory protein-1α (MIP-1α), as well as MIP-2. Furthermore, SP also increased NF-κB activation. The stimulatory effect of SP was specific to chemokine synthesis through the NF-κB pathway, since the increase in chemokine production was completely attenuated when pancreatic acini were pretreated with the selective NF-κB inhibitor NF-κB essential modulator-binding domain peptide. This study shows that SP-induced chemokine synthesis in mouse pancreatic acinar cells is NF-κB dependent.

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