scholarly journals Endangered Lymphocytes: The Effects of Alloxan and Streptozotocin on Immune Cells in Type 1 Induced Diabetes

2021 ◽  
Vol 2021 ◽  
pp. 1-15
Author(s):  
Luiz A. D. Queiroz ◽  
Josiane B. Assis ◽  
João P. T. Guimarães ◽  
Emanuella S. A. Sousa ◽  
Anália C. Milhomem ◽  
...  
Keyword(s):  
Immune Cell ◽  
Early Stage ◽  
Chronic Phase ◽  
Treated Group ◽  
Inflammatory Infiltration ◽  
Cell Parameters ◽  
Pancreatic Islets Of Langerhans

Alloxan (ALX) and streptozotocin (STZ) are extensively used to induce type 1 diabetes (T1D) in animal models. This study is aimed at evaluating the differences in immune parameters caused by ALX and STZ. T1D was induced either with ALX or with STZ, and the animals were followed for up to 180 days. Both ALX and STZ induced a decrease in the total number of circulating leukocytes and lymphocytes, with an increase in granulocytes when compared to control mice (CT). STZ-treated mice also exhibited an increase in neutrophils and a reduction in the lymphocyte percentage in the bone marrow. In addition, while the STZ-treated group showed a decrease in total CD3+, CD4-CD8+, and CD4+CD8+ T lymphocytes in the thymus and CD19+ B lymphocytes in the pancreas and spleen, the ALX group showed an increase in CD4-CD8+ and CD19+ only in the thymus. Basal levels of splenic interleukin- (IL-) 1β and pancreatic IL-6 in the STZ group were decreased. Both diabetic groups showed atrophy of the thymic medulla and degeneration of pancreatic islets of Langerhans composed of inflammatory infiltration and hyperemia with vasodilation. ALX-treated mice showed a decrease in reticuloendothelial cells, enhanced lymphocyte/thymocyte cell death, and increased number of Hassall’s corpuscles. Reduced in vitro activation of splenic lymphocytes was found in the STZ-treated group. Furthermore, mice immunized with ovalbumin (OVA) showed a more intense antigen-specific paw edema response in the STZ-treated group, while production of anti-OVA IgG1 antibodies was similar in both groups. Thereby, important changes in immune cell parameters in vivo and in vitro were found at an early stage of T1D in the STZ-treated group, whereas alterations in the ALX-treated group were mostly found in the chronic phase of T1D, including increased mortality rates. These findings suggest that the effects of ALX and STZ influenced, at different times, lymphoid organs and their cell populations.

scholarly journals Fibroblast membrane-camouflaged nanoparticles for inflammation treatment in the early stage

2021 ◽  
Vol 13 (1) ◽  
Author(s):  
Lizhong Sun ◽  
Libang He ◽  
Wei Wu ◽  
Li Luo ◽  
Mingyue Han ◽  
...  
Keyword(s):  
Cell Membrane ◽  
Immune Cell ◽  
Early Stage ◽  
Specific Treatment ◽  
Cell Types ◽  
Loss Of Function ◽  
Tissue Repair And Regeneration ◽  
Inflammatory Conditions

AbstractUnrestrained inflammation is harmful to tissue repair and regeneration. Immune cell membrane-camouflaged nanoparticles have been proven to show promise as inflammation targets and multitargeted inflammation controls in the treatment of severe inflammation. Prevention and early intervention of inflammation can reduce the risk of irreversible tissue damage and loss of function, but no cell membrane-camouflaged nanotechnology has been reported to achieve stage-specific treatment in these conditions. In this study, we investigated the prophylactic and therapeutic efficacy of fibroblast membrane-camouflaged nanoparticles for topical treatment of early inflammation (early pulpitis as the model) with the help of in-depth bioinformatics and molecular biology investigations in vitro and in vivo. Nanoparticles have been proven to act as sentinels to detect and competitively neutralize invasive Escherichia coli lipopolysaccharide (E. coli LPS) with resident fibroblasts to effectively inhibit the activation of intricate signaling pathways. Moreover, nanoparticles can alleviate the secretion of multiple inflammatory cytokines to achieve multitargeted anti-inflammatory effects, attenuating inflammatory conditions in the early stage. Our work verified the feasibility of fibroblast membrane-camouflaged nanoparticles for inflammation treatment in the early stage, which widens the potential cell types for inflammation regulation.

scholarly journals A miRNA181a/NFAT5 axis links impaired T cell tolerance induction with autoimmune type 1 diabetes

2018 ◽  
Vol 10 (422) ◽  
pp. eaag1782 ◽  
Author(s):  
Isabelle Serr ◽  
Martin G. Scherm ◽  
Adam M. Zahm ◽  
Jonathan Schug ◽  
Victoria K. Flynn ◽  
...  
Keyword(s):  
T Cells ◽  
Type 1 Diabetes ◽  
T Cell ◽  
Early Stage ◽  
Tolerance Induction ◽  
Islet Autoimmunity ◽  
Activated T Cells

Molecular checkpoints that trigger the onset of islet autoimmunity or progression to human type 1 diabetes (T1D) are incompletely understood. Using T cells from children at an early stage of islet autoimmunity without clinical T1D, we find that a microRNA181a (miRNA181a)–mediated increase in signal strength of stimulation and costimulation links nuclear factor of activated T cells 5 (NFAT5) with impaired tolerance induction and autoimmune activation. We show that enhancing miRNA181a activity increases NFAT5 expression while inhibiting FOXP3+ regulatory T cell (Treg) induction in vitro. Accordingly, Treg induction is improved using T cells from NFAT5 knockout (NFAT5ko) animals, whereas altering miRNA181a activity does not affect Treg induction in NFAT5ko T cells. Moreover, high costimulatory signals result in phosphoinositide 3-kinase (PI3K)–mediated NFAT5, which interferes with FoxP3+ Treg induction. Blocking miRNA181a or NFAT5 increases Treg induction in murine and humanized models and reduces murine islet autoimmunity in vivo. These findings suggest targeting miRNA181a and/or NFAT5 signaling for the development of innovative personalized medicines to limit islet autoimmunity.

scholarly journals NOX4/H 2 O 2 /mTORC1 Pathway in Salt-Induced Hypertension and Kidney Injury

Hypertension ◽  
2020 ◽  
Vol 76 (1) ◽  
pp. 133-143 ◽  
Author(s):  
Vikash Kumar ◽  
Theresa Kurth ◽  
Nadezhda N. Zheleznova ◽  
Chun Yang ◽  
Allen W. Cowley
Keyword(s):  
Renal Injury ◽  
Immune Cell ◽  
Salt Intake ◽  
Chronic Phase ◽  
Kidney Injury ◽  
High Salt ◽  
High Salt Intake ◽  
Induced Hypertension

We have reported that a high-salt (4.0% NaCl) dietary intake activates mTORC1 and inhibition of this pathway with rapamycin blunts the chronic phase of salt-induced hypertension and renal injury in Dahl salt-sensitive (SS) rats. In SS rats, high-salt intake is known to increase the renal production of H 2 O 2 by NOX4, the most abundant NOX isoform in the kidney, and the global knockout of NOX4 blunts salt-sensitivity in these rats. Here, we explored the hypothesis that elevations of H 2 O 2 by NOX4 in high-salt fed SS rat stimulate mTORC1 for the full development of salt-induced hypertension and renal injury. Our in vitro studies found that H 2 O 2 activates mTORC1 independent of PI3K/AKT and AMPK pathways. To determine the in vivo relevance of NOX4/H 2 O 2 /mTORC1 in the salt-induced hypertension, SS- Nox4 knockout (SS Nox4 −/− ) rats were daily administrated with vehicle/rapamycin fed a high-salt diet for 21 days. Rapamycin treatment of SS Nox4−/− rats had shown no augmented effect on the salt-induced hypertension nor upon indices of renal injury. Significant reductions of renal T lymphocyte and macrophage together with inhibition of cell proliferation were observed in rapamycin treated rats suggesting a role of mTORC1 independent of NOX4 in the proliferation of immune cell. Given the direct activation of mTORC1 by H 2 O 2 and absence of any further protection from salt-induced hypertension in rapamycin-treated SS Nox4 −/− rats, we conclude that NOX4-H 2 O 2 is a major upstream activator of mTORC1 that contributes importantly to salt-induced hypertension and renal injury in the SS rat model.

scholarly journals GZMKhigh CD8+ T effector memory cells are associated with CD15high neutrophil abundance in early-stage colorectal tumors and predict poor clinical outcome.

2021 ◽  
Author(s):  
Silvia Tiberti ◽  
Carlotta Catozzi ◽  
Caterina Scirgolea ◽  
Ottavio Croci ◽  
Mattia Ballerini ◽  
...  
Keyword(s):  
T Cells ◽  
Clinical Outcome ◽  
Cd8 T Cells ◽  
Immune Cell ◽  
Early Stage ◽  
Effector Memory ◽  
Functional Changes

Tumor contexture has emerged as a major determinant to establish prognosis and guide novel therapies and tumor infiltrating CD8+ T cells have been associated with a better prognosis in several solid tumors, including early-stage colorectal cancer (CRC). However, the tumor immune infiltrate is highly heterogeneous and understanding how the interplay between different immune cell compartments impacts on the clinical outcome is still in its infancy. Here, we describe in a prospective cohort a novel CD8+ T effector memory population, which is characterized by high levels of Granzyme K (GZMKhigh CD8+ TEM) and correlated with CD15high tumor infiltrating neutrophils. We provide both in vitro and in vivo evidence of the role of stromal cell-derived factor 1 (CXCL12/SDF-1) in driving functional changes on neutrophils at the tumor site, promoting their retention and increasing crosstalk with CD8+ T cells. Mechanistically, as a consequence of the interaction with neutrophils, CD8+ T cells are skewed towards a CD8+ TEM phenotype, producing high levels of GZMK, which in turn decreased E-cadherin pathway. The correlation of GZMKhigh CD8+ TEM and neutrophils with both tumor progression in mice and early relapse in CRC patients demonstrate the role of GZMKhigh CD8+ TEM in promoting malignancy. Indeed, a gene signature defining GZMKhigh CD8+ TEM was associated with worse prognosis on a larger independent cohort of CRC patients and a similar analysis was extended to lung cancer (TCGA). Overall, our results highlight the emergence of GZMKhigh CD8+ TEM in early-stage CRC tumors as a hallmark driven by the interaction with neutrophils, which could implement current patient stratification and be targeted by novel therapeutics.

scholarly journals Endogenous Interleukin 4 Is Required for Development of Protective CD4+ T Helper Type 1 Cell Responses to Candida albicans

1998 ◽  
Vol 187 (3) ◽  
pp. 307-317 ◽  
Author(s):  
Antonella Mencacci ◽  
Giuseppe Del Sero ◽  
Elio Cenci ◽  
Cristiana Fè d'Ostiani ◽  
Angela Bacci ◽  
...  
Keyword(s):  
Candida Albicans ◽  
Early Stage ◽  
Interleukin 4 ◽  
T Helper ◽  
Ifn Γ ◽  
Deficient Mice ◽  
Helper Type

Interleukin (IL)-4–deficient mice were used to assess susceptibility to systemic or gastrointestinal Candida albicans infections, as well as parameters of innate and elicited T helper immunity. In the early stage of systemic infection with virulent C. albicans, an unopposed interferon (IFN)-γ response renders IL-4–deficient mice more resistant than wild-type mice to infection. Yet, IL-4–deficient mice failed to efficiently control infection in the late stage and succumbed to it. Defective IFN-γ and IL-12 production, but not IL-12 responsiveness, was observed in IL-4–deficient mice that failed to mount protective T helper type 1 cell (Th1)-mediated acquired immunity in response to a live vaccine strain of the yeast or upon mucosal immunization in vivo. In vitro, IL-4 primed neutrophils for cytokine release, including IL-12. However, late treatment with exogenous IL-4, while improving the outcome of infection, potentiated CD4+ Th1 responses even in the absence of neutrophils. These findings indicate that endogenous IL-4 is required for the induction of CD4+ Th1 protective antifungal responses, possibly through the combined activity on cells of the innate and adaptive immune systems.

scholarly journals The ND10 Component Promyelocytic Leukemia Protein Relocates to Human Papillomavirus Type 1 E4 Intranuclear Inclusion Bodies in Cultured Keratinocytes and in Warts

2003 ◽  
Vol 77 (1) ◽  
pp. 673-684 ◽  
Author(s):  
Sally Roberts ◽  
Michele L. Hillman ◽  
Gillian L. Knight ◽  
Phillip H. Gallimore
Keyword(s):  
Human Papillomavirus ◽  
Early Stage ◽  
Promyelocytic Leukemia ◽  
Genome Replication ◽  
Dna Viruses ◽  
Promyelocytic Leukemia Protein ◽  
Efficient Replication

ABSTRACT Human papillomavirus type 1 (HPV1) E4 protein is associated with cytoplasmic and nuclear inclusions in productively infected keratinocytes. Here we have used transient expression of HPV1 E4 (also known as E1^E4) protein in keratinocytes to reproduce formation of E4 inclusions. Immunofluorescence analysis showed that progressive formation of inclusions correlated with diminished colocalization between E4 and keratin intermediate filaments (IFs). Our results support a model in which the HPV1 E4-keratin IF association is transient, occurring only at an early stage of inclusion formation. We also demonstrate that E4 induces relocation of the promyelocytic leukemia protein (PML) from multiple intranuclear speckles (ND10 bodies) to the periphery of nuclear E4 inclusions and that this activity is specific to full-length E4 protein. Analysis of HPV1-induced warts demonstrated that nuclear PML-E4 inclusions were present in productively infected keratinocytes, indicating that reorganization of PML occurs during the virus's replication cycle. It has been suggested that ND10 bodies are the sites for papillomavirus genome replication and virion assembly. Our finding that E4 induces reorganization of ND10 bodies in vitro and in vivo is further strong evidence that these domains play an important role in the papillomavirus life cycle. This study indicates that HPV1 is analogous to other DNA viruses that disrupt or reorganize ND10 domains, possibly to increase efficiency of virus infection. We hypothesize that HPV1 E4-induced reorganization of PML is necessary for efficient replication of the virus during the virus-producing phase.

Exosome-based immunotherapies in ovarian cancer development of preclinical models and therapeutics

2021 ◽  
Author(s):  
◽  
Simone Pisano
Keyword(s):  
Ovarian Cancer ◽  
Immune Cell ◽  
Early Stage ◽  
Advanced Ovarian Cancer ◽  
Cancer Therapeutics ◽  
Multicellular Spheroids ◽  
Early Stage Disease ◽  
Main Research

Treatment of ovarian cancer (OC) continues to present clinical challenges. It remains difficult to diagnose early stage disease, and because of this generally presents as advanced stage, with limited therapeutic options and often the development of resistance to chemotherapy. Furthermore, OC is considered as an immunologically “cold” tumour based on the poor response to immunotherapies. This lack of response to immunotherapy remains poorly understood, hence better models are needed in order to elucidate the fundamental mechanisms behind tumour immunosuppression, and for new and innovative therapeutic strategies to be tested. Exosomes have recently emerged as crucial players in the cell-cell communication and content exchange within the tumour microenvironment and have also been investigated for their capacity to act as cancer therapeutics or to be re-engineered to increase their performances and effects. In this work, two main research areas were explored. The first one focused on advanced ovarian cancer modelling. Indeed, the in vitro formation of multicellular spheroids that included a mixture of cancer cells and different macrophage phenotypes was optimised, and their characteristics explored. Additionally, an in vivo advanced OC model was created from immunocompetent mice and the tumours were characterised for their immune infiltrates presence. The ascitic fluid that arose from the tumour-bearing mice was also comprehensively analysed for its immune cells content by mass cytometry for the first time in an ovarian cancer setting. The second part of the work involved the exploration of two innovative OC therapeutics. Dendritic-cell (DC) derived exosomes were obtained from tumour antigen-pulsed DCs and tested for their efficacy both in vitro and in vivo. A semi-synthetic exosomes approach was also tested by forcing monocytic cells through pores of different sizes and obtaining Immune (Cell) Derived Exosome Mimetics (IDEM). IDEM were characterised and tested in vitro on both 2D and spheroid systems.

707 Discovery of a novel EP2 and EP4 dual antagonist

2020 ◽  
Vol 8 (Suppl 3) ◽  
pp. A749-A749
Author(s):  
Yeri Lee ◽  
Hyun Jin Kim ◽  
Donggeon Kim ◽  
Joo Youn Lee ◽  
Chang Soo Yun ◽  
...  
Keyword(s):  
Cell Function ◽  
Immune Cell ◽  
Radioligand Binding ◽  
Early Stage ◽  
Scintillation Counter ◽  
Hek293 Cells ◽  
List Type ◽  
Camp Levels

BackgroundProstaglandin E2 (PGE2) is one of the most abundant prostaglandins, with crucial roles in normal and pathologic physiology. Especially, PGE2 levels are abnormally elevated in many cancers, and high levels of PGE2 are known to be pro-tumorigenic, likely due to the immune suppressive effect in the tumor microenvironment.1–4 There are four types of PGE2 receptors; EP1, EP2, EP3 and EP4. Among them, EP2 and EP4 activate adenylate cyclase and increase cAMP levels, which induce the cAMP-dependent protein kinase (PKA) signaling pathway. EP2 and EP4 are expressed in various immune cells (e.g. macrophages, dendritic cells, NK cells and CTLs), and genetic and pharmacological inhibition of EP2 and EP4 increases immune activity and suppresses tumor growth.MethodsTo evaluate the binding affinity against EP2 and EP4, a radioligand binding assay was conducted using EP2 or EP4 transfected HEK293 cells. Cell membrane homogenates were incubated with [3H]PGE2 in the absence or presence of the test compounds. Following incubation, the samples were filtered rapidly under vacuum through glass fiber filters and rinsed several times with cold Tris-HCl. The filters were dried then counted for radioactivity in a scintillation counter using a scintillation cocktail. The results were expressed as a percent inhibition of the control radioligand specific binding.The antagonistic activity against EP2 and EP4 was assessed via LANCE Ultra cAMP assay (PerkinElmer). HEK293 cells overexpressing EP2 or EP4 were seeded into the plate and treated by PGE2 and compounds. After 30 minutes of incubation, cAMP levels were measured by FRET signal using Varioskan plate reader, following the manufacturer’s protocol.Anti-tumor activity of KT-00113 was evaluated using LLC1 syngeneic model. When tumor volume reached approximatively 100 mm3, mice were treated PO, QD. Tumor size was measured twice every week.ResultsSystematic structure-activity relationship (SAR) investigation identified novel EP2 and EP4 dual antagonists. The most promising compound KT-00113 possesses high potency against both EP2 and EP4, while maintaining high selectivity over other prostanoid receptors. In vitro and in vivo ADMET studies show that KT-00113 has a favorable profile, apt for further examination in in vivo cancer models and immune cell function in tumors.ConclusionsKT-00113, a highly potent and selective EP2/4 dual antagonist has strong potential to become the best-in-class immune suppression lifting cancer immunotherapy and may be suitable for further development in a clinical setting.ReferencesCordes T, Hoellen F, Dittmer C, Salehin D, Kummel S, Friedrich M, Koster F, Becker S, Diedrich K, Thill M. Correlation of prostaglandin metabolizing enzymes and serum PGE2 levels with vitamin D receptor and serum 25(OH)2D3 levels in breast and ovarian cancer. Anticancer Res;32 ( 2012):351–357.Diakowska D, Markocka-Maczka K, Nienartowicz M, Lewandowski A, Grabowski K. Increased level of serum prostaglandin-2 in early stage of esophageal squamous cell carcinoma, Arch Med Sci ( 2014);10:956–961.Akbari N, Ghorbani M, Salimi V, Alimohammadi A, Khamseh ME, Akbari H, Nourbakhsh M, Sheikhi A, Taghavi SF, Tavakoli-Yaraki M. Cyclooxygenase enzyme and PGE2 expression in patients with functional and non-functional pituitary adenomas. BMC Endocr Disord 2020;20:39.Gomes RN, Felipe da Costa S, Colquhoun A. Eicosanoids and cancer, Clinics (Sao Paulo), 73 ( 2018) e530s.

Sectioned rubisco crystals in TEM

1990 ◽  
Vol 48 (3) ◽  
pp. 664-665
Author(s):  
Gunnel Karlsson ◽  
Jan-Olov Bovin ◽  
Michael Bosma
Keyword(s):  
Plant Cell ◽  
Carbon Fixation ◽  
Unit Cell ◽  
Protein Crystals ◽  
Unit Cell Parameters ◽  
Cell Parameters ◽  
Photosynthetic Carbon Fixation ◽  
Photosynthetic Carbon

RuBisCO (D-ribulose-l,5-biphosphate carboxylase/oxygenase) is the most aboundant enzyme in the plant cell and it catalyses the key carboxylation reaction of photosynthetic carbon fixation, but also the competing oxygenase reaction of photorespiation. In vitro crystallized RuBisCO has been studied earlier but this investigation concerns in vivo existance of RuBisCO crystals in anthers and leaves ofsugarbeets. For the identification of in vivo protein crystals it is important to be able to determinethe unit cell of cytochemically identified crystals in the same image. In order to obtain the best combination of optimal contrast and resolution we have studied different staining and electron accelerating voltages. It is known that embedding and sectioning can cause deformation and obscure the unit cell parameters.

Sign in / Sign up

Export Citation Format

Share Document