scholarly journals Treg cells maintain selective access to IL-2 and immune homeostasis despite substantially reduced CD25 function

2019 ◽  
Author(s):  
Erika T. Hayes ◽  
Cassidy E. Hagan ◽  
Daniel J. Campbell
Keyword(s):  
Patient Outcomes ◽  
Interleukin 2 ◽  
Treg Cells ◽  
Immune Homeostasis ◽  
Cd25 Expression ◽  
And Function ◽  
Precise Role ◽  
Selective Access

AbstractInterleukin-2 (IL-2) is a critical regulator of immune homeostasis through its impact on both regulatory T (Treg) and effector T (Teff) cells. However, the precise role of IL-2 in the maintenance and function of Treg cells in the adult peripheral immune system remains unclear. Here, we report that neutralization of IL-2 abrogated all IL-2 receptor signaling in Treg cells, resulting in rapid dendritic cell (DC) activation and subsequent Teff cell proliferation. By contrast, despite substantially reduced IL-2 sensitivity, Treg cells maintained selective IL-2 signaling and prevented immune dysregulation following treatment with the inhibitory anti-CD25 antibody PC61, even when CD25hi Treg cells were depleted. Thus, despite severely curtailed CD25 expression and function, Treg cells retain selective access to IL-2 that supports their anti-inflammatory functions in vivo. Antibody-mediated targeting of CD25 is being actively pursued for treatment of autoimmune disease and preventing allograft rejection, and our findings help inform therapeutic manipulation and design for optimal patient outcomes.

scholarly journals STAT6 Is Critical for the Induction of Regulatory T Cells In Vivo Controlling the Initial Steps of Colitis-Associated Cancer

2021 ◽  
Vol 22 (8) ◽  
pp. 4049
Author(s):  
Yael Delgado-Ramirez ◽  
Angel Ocaña-Soriano ◽  
Yadira Ledesma-Soto ◽  
Jonadab E. Olguín ◽  
Joselín Hernandez-Ruiz ◽  
...  
Keyword(s):  
Treg Cells ◽  
Tumor Formation ◽  
Mucosal Inflammation ◽  
Direct Role ◽  
Early Stages ◽  
Main Driver ◽  
Induce Resistance ◽  
And Function

Inflammation is the main driver of the tumor initiation and progression in colitis-associated colorectal cancer (CAC). Recent findings have indicated that the signal transducer and activator of transcription 6 (STAT6) plays a fundamental role in the early stages of CAC, and STAT6 knockout (STAT6−/−) mice are highly resistant to CAC development. Regulatory T (Treg) cells play a major role in coordinating immunomodulation in cancer; however, the role of STAT6 in the induction and function of Treg cells is poorly understood. To clarify the contribution of STAT6 to CAC, STAT6−/− and wild type (WT) mice were subjected to an AOM/DSS regimen, and the frequency of peripheral and local Treg cells was determined during the progression of CAC. When STAT6 was lacking, a remarkable reduction in tumor growth was observed, which was associated with decreased inflammation and an increased number of CD4+CD25+Foxp3+ cells in the colon, circulation, and spleen, including an over-expression of TGF-beta, IL-10, and Foxp3, compared to WT mice, during the early stages of CAC development. Conversely, WT mice showed an inverse frequency of Treg cells compared with STAT6−/− mice, which was followed by intestinal tumor formation. Increased mucosal inflammation, histological damage, and tumorigenesis were restored to levels observed in WT mice when an early inhibition/depletion of Treg cells was performed in STAT6−/− mice. Thus, with STAT6 deficiency, an increased number of Treg cells induce resistance against tumorigenesis, arresting tumor-promoting inflammation. We reported a direct role of STAT6 in the induction and function of Treg cells during CAC development and suggest that STAT6 is a potential target for the modulation of immune response in colitis and CAC.

scholarly journals Low-dose IL-2 in the treatment of immune-related diseases

2021 ◽  
Vol 19 ◽  
pp. 205873922110399
Author(s):  
Jiakui Zhang ◽  
Yong Huang
Keyword(s):  
T Cells ◽  
Adverse Reactions ◽  
Low Dose ◽  
Interleukin 2 ◽  
Treg Cells ◽  
High Dose ◽  
Proliferation And Differentiation ◽  
Made In

Since the discovery of interleukin-2 (IL-2) in 1979, increasing attention has been focused on its role in regulating immune function. IL-2 has been found to play an important role in maintaining autoimmune tolerance, and it is essential for the proliferation and differentiation of regulatory T cells (Treg) cells. Other studies have found that the role of IL-2 in vivo is closely related to its concentration. Low-dose IL-2 selectively stimulates the proliferation of Treg cells in vivo, while high-dose IL-2 primarily promotes the proliferation of effector T cells. In view of these findings, an increasing number of studies have focused on the use of low-dose IL-2 in the treatment of immune-related diseases in recent years. The results have been encouraging, with mild adverse reactions. This article mainly focuses on the latest progress made in the IL-2 treatment of immune-related diseases and its regulatory effect on the immune status in different diseases, providing a reference for the rational clinical application of IL-2.

scholarly journals Efficient IL-2R signaling differentially affects the stability, function, and composition of the regulatory T-cell pool

2021 ◽  
Author(s):  
Marc Permanyer ◽  
Berislav Bošnjak ◽  
Silke Glage ◽  
Michaela Friedrichsen ◽  
Stefan Floess ◽  
...  
Keyword(s):  
T Cell ◽  
Treg Cell ◽  
Cell Function ◽  
Interleukin 2 ◽  
Foxp3 Expression ◽  
Treg Cells ◽  
Receptor Expression ◽  
Spontaneous Mutant ◽  
Cell Pool ◽  
And Function

AbstractSignaling via interleukin-2 receptor (IL-2R) is a requisite for regulatory T (Treg) cell identity and function. However, it is not completely understood to what degree IL-2R signaling is required for Treg cell homeostasis, lineage stability and function in both resting and inflammatory conditions. Here, we characterized a spontaneous mutant mouse strain endowed with a hypomorphic Tyr129His variant of CD25, the α-chain of IL-2R, which resulted in diminished receptor expression and reduced IL-2R signaling. Under noninflammatory conditions, Cd25Y129H mice harbored substantially lower numbers of peripheral Treg cells with stable Foxp3 expression that prevented the development of spontaneous autoimmune disease. In contrast, Cd25Y129H Treg cells failed to efficiently induce immune suppression and lost lineage commitment in a T-cell transfer colitis model, indicating that unimpaired IL-2R signaling is critical for Treg cell function in inflammatory environments. Moreover, single-cell RNA sequencing of Treg cells revealed that impaired IL-2R signaling profoundly affected the balance of central and effector Treg cell subsets. Thus, partial loss of IL-2R signaling differentially interferes with the maintenance, heterogeneity, and suppressive function of the Treg cell pool.

scholarly journals Action of taxol on mitosis: modification of microtubule arrangements and function of the mitotic spindle in Haemanthus endosperm.

1983 ◽  
Vol 96 (2) ◽  
pp. 527-540 ◽  
Author(s):  
J Molè-Bajer ◽  
A S Bajer
Keyword(s):  
Equatorial Region ◽  
Polar Regions ◽  
Higher Plant ◽  
Chromosome Fragments ◽  
Immunocytochemical Method ◽  
And Function ◽  
Spindle Function ◽  
Direction Opposite

We have studied the effect of taxol on mitosis in Haemanthus endosperm. Immuno-Gold Stain (IGS), a new immunocytochemical method (17), was used to visualize microtubules (MTs) in the light microscope. Observations on MT arrangements were correlated with studies in vivo. Chromosome movements are affected in all stages of mitosis which progresses over at least 10(4) range of taxol concentrations. The three most characteristic effects on MTs are: (a) enhancement of the lateral associations between MTs, seen especially during the reorganization of the polar region of the spindle, (b) promotion of MT assembly, leading to the formation of additional MTs in the spindle and MT arrays in the cytoplasm, and (c) an increase in MT stability, demonstrated in their increased cold resistance. In this report, the emphasis is on the primary, immediate effects, occurring in the first 30 min of taxol action. Effects are detected after a few mins, are reversible, and are concentration/time dependent. The spindle and phragmoplast are remarkably modified due to the enhancement of lateral associations of MTs and the formation of abundant nonkinetochore and polar, asterlike MTs. The equatorial region of the interzone in anaphase may be entirely depleted of MTs, and the spindle may break perpendicular to the spindle axis. Mitosis is completed in these conditions, providing evidence for the motile autonomy of each half-spindle. Trailing chromosome arms in anaphase are often stretched and broken. Chromosome fragments are transported away from the polar regions, i.e., in the direction opposite to that expected (5, 6). This supplies the first direct evidence of pushing by elongating MTs in an anastral higher plant spindle. These observations draw attention to the relation between the lateral association of MT ends to assembly/disassembly and to the role of such an interaction in spindle function and organization.

scholarly journals In Vivo Role of Focal Adhesion Kinase in Regulating Pancreatic  -Cell Mass and Function Through Insulin Signaling, Actin Dynamics, and Granule Trafficking

Diabetes ◽  
2012 ◽  
Vol 61 (7) ◽  
pp. 1708-1718 ◽  
Author(s):  
E. P. Cai ◽  
M. Casimir ◽  
S. A. Schroer ◽  
C. T. Luk ◽  
S. Y. Shi ◽  
...  
Keyword(s):  
Focal Adhesion Kinase ◽  
Focal Adhesion ◽  
Insulin Signaling ◽  
Cell Mass ◽  
Actin Dynamics ◽  
Pancreatic Cell ◽  
And Function

scholarly journals Netrin-1 in Atherosclerosis: Relationship between Human Macrophage Intracellular Levels and In Vivo Plaque Morphology

Biomedicines ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 168
Author(s):  
Susanna Fiorelli ◽  
Nicola Cosentino ◽  
Benedetta Porro ◽  
Franco Fabbiocchi ◽  
Giampaolo Niccoli ◽  
...  
Keyword(s):  
Progressive Increase ◽  
Human Macrophage ◽  
Plaque Morphology ◽  
Artery Disease ◽  
Atherosclerotic Process ◽  
And Function ◽  
And Control ◽  
Macrophage Accumulation

Netrin-1 is a laminin-like protein that plays a pivotal role in cell migration and, according to the site of its release, exerts both pro and anti-atherosclerotic functions. Macrophages, key cells in atherosclerosis, are heterogeneous in morphology and function and different subpopulations may support plaque progression, stabilization, and/or regression. Netrin-1 was evaluated in plasma and, together with its receptor UNC5b, in both spindle and round monocyte-derived macrophages (MDMs) morphotypes from coronary artery disease (CAD) patients and control subjects. In CAD patients, plaque features were detected in vivo by optical coherence tomography. CAD patients had lower plasma Netrin-1 levels and a higher MDMs expression of both protein and its receptor compared to controls. Specifically, a progressive increase in Netrin-1 and UNC5b was evidenced going from controls to stable angina (SA) and acute myocardial infarction (AMI) patients. Of note, spindle MDMs of AMI showed a marked increase of both Netrin-1 and its receptor compared to spindle MDMs of controls. UNC5b expression is always higher in spindle compared to round MDMs, regardless of the subgroup. Finally, CAD patients with higher intracellular Netrin-1 levels showed greater intraplaque macrophage accumulation in vivo. Our findings support the role of Netrin-1 and UNC5b in the atherosclerotic process.

The role of metalloproteinases and their inhibitors in regulating mammary epithelial morphology and function in vivo

1995 ◽  
Vol 2 (3) ◽  
pp. 401-411 ◽  
Author(s):  
Carolyn J. Sympson ◽  
Rabih S. Talhouk ◽  
Mina J. Bissell ◽  
Zena Werb
Keyword(s):  
Mammary Epithelial ◽  
Epithelial Morphology ◽  
And Function

scholarly journals In Vivo Role of Dendritic Cells in a Murine Model of Pulmonary Cryptococcosis

2006 ◽  
Vol 74 (7) ◽  
pp. 3817-3824 ◽  
Author(s):  
Karen L. Wozniak ◽  
Jatin M. Vyas ◽  
Stuart M. Levitz
Keyword(s):  
T Cells ◽  
Dendritic Cells ◽  
T Cell Activation ◽  
Cell Activation ◽  
Ex Vivo ◽  
Interleukin 2 ◽  
Mouse Lung

ABSTRACT Dendritic cells (DC) have been shown to phagocytose and kill Cryptococcus neoformans in vitro and are believed to be important for inducing protective immunity against this organism. Exposure to C. neoformans occurs mainly by inhalation, and in this study we examined the in vivo interactions of C. neoformans with DC in the lung. Fluorescently labeled live C. neoformans and heat-killed C. neoformans were administered intranasally to C57BL/6 mice. At specific times postinoculation, mice were sacrificed, and lungs were removed. Single-cell suspensions of lung cells were prepared, stained, and analyzed by microscopy and flow cytometry. Within 2 h postinoculation, fluorescently labeled C. neoformans had been internalized by DC, macrophages, and neutrophils in the mouse lung. Additionally, lung DC from mice infected for 7 days showed increased expression of the maturation markers CD80, CD86, and major histocompatibility complex class II. Finally, ex vivo incubation of lung DC from infected mice with Cryptococcus-specific T cells resulted in increased interleukin-2 production compared to the production by DC from naïve mice, suggesting that there was antigen-specific T-cell activation. This study demonstrated that DC in the lung are capable of phagocytosing Cryptococcus in vivo and presenting antigen to C. neoformans-specific T cells ex vivo, suggesting that these cells have roles in innate and adaptive pulmonary defenses against cryptococcosis.

scholarly journals An expanded population of pathogenic regulatory T cells in giant cell arteritis is abrogated by IL-6 blockade therapy

2016 ◽  
Vol 76 (5) ◽  
pp. 898-905 ◽  
Author(s):  
Chie Miyabe ◽  
Yoshishige Miyabe ◽  
Klemen Strle ◽  
Nancy D Kim ◽  
John H Stone ◽  
...  
Keyword(s):  
Giant Cell Arteritis ◽  
Giant Cell ◽  
Treg Cells ◽  
Therapeutic Effects ◽  
Exon 2 ◽  
Disease Remission ◽  
Randomised Controlled ◽  
And Function ◽  
Active Disease

ObjectivesRandomised-controlled trials have recently proven the efficacy of the interleukin (IL)-6 receptor antagonist tocilizumab (TCZ) in giant cell arteritis (GCA). However, the mechanism of action of IL-6 blockade in this disease is unknown. Moreover, the role of regulatory T (Treg) cells in the pathogenesis of GCA remains underexplored. Given the plasticity of Tregs and the importance of IL-6 in their biology, we hypothesised that TCZ might modulate the Treg response in GCA. We therefore characterised the Treg compartment of patients with GCA treated with TCZ.MethodsWe classified 41 patients with GCA into three groups: active disease (aGCA, n=11), disease remission on corticosteroids (rGCA-CS, n=19) and disease remission on TCZ (rGCA-TCZ, n=11). Healthy controls (HCs) were included for comparison. We determined the frequency, phenotype and function of peripheral blood Tregs.ResultsPatients with aGCA demonstrated a hypoproliferating Treg compartment enriched in IL-17-secreting Tregs (IL-17+Tregs). Tregs in patients with aGCA disproportionally expressed a hypofunctional isoform of Foxp3 that lacks exon 2 (Foxp3Δ2). Foxp3Δ2-expressing Tregs coexpressed CD161, a marker commonly associated with the Th17 linage, significantly more often than full-length Foxp3-expressing Tregs. Compared with those of HCs, GCA-derived Tregs demonstrated impaired suppressor capacity. Treatment with TCZ, in contrast to CS therapy, corrected the Treg abnormalities observed in aGCA. In addition, TCZ treatment increased the numbers of activated Tregs (CD45RA−Foxp3high) and the Treg expression of markers of trafficking (CCR4) and terminal differentiation (CTLA-4).ConclusionsTCZ may exert its therapeutic effects in GCA by increasing the proliferation and activation of Tregs, and by reverting the pathogenic Treg phenotype seen during active disease.

scholarly journals Immunoproteasomes as a novel antiviral mechanism in rhinovirus-infected airways

2018 ◽  
Vol 132 (15) ◽  
pp. 1711-1723 ◽  
Author(s):  
Kris Genelyn Dimasuay ◽  
Amelia Sanchez ◽  
Niccolette Schaefer ◽  
Jorge Polanco ◽  
Deborah A. Ferrington ◽  
...  
Keyword(s):  
Viral Load ◽  
Antigen Processing ◽  
Lower Airway ◽  
Chronic Obstructive ◽  
Deficient Mouse ◽  
Obstructive Pulmonary Disease ◽  
Tracheal Epithelial Cells ◽  
And Function

Rhinovirus (RV) infection is involved in acute exacerbations of asthma and chronic obstructive pulmonary disease (COPD). RV primarily infects upper and lower airway epithelium. Immunoproteasomes (IP) are proteolytic machineries with multiple functions including the regulation of MHC class I antigen processing during viral infection. However, the role of IP in RV infection has not been explored. We sought to investigate the expression and function of IP during airway RV infection. Primary human tracheobronchial epithelial (HTBE) cells were cultured at air–liquid interface (ALI) and treated with RV16, RV1B, or interferon (IFN)-λ in the absence or presence of an IP inhibitor (ONX-0914). IP gene (i.e. LMP2) deficient mouse tracheal epithelial cells (mTECs) were cultured for the mechanistic studies. LMP2-deficient mouse model was used to define the in vivo role of IP in RV infection. IP subunits LMP2 and LMP7, antiviral genes MX1 and OAS1 and viral load were measured. Both RV16 and RV1B significantly increased the expression of LMP2 and LMP7 mRNA and proteins, and IFN-λ mRNA in HTBE cells. ONX-0914 down-regulated MX1 and OAS1, and increased RV16 load in HTBE cells. LMP2-deficient mTECs showed a significant increase in RV1B load compared with the wild-type (WT) cells. LMP2-deficient (compared with WT) mice increased viral load and neutrophils in bronchoalveolar lavage (BAL) fluid after 24 h of RV1B infection. Mechanistically, IFN-λ induction by RV infection contributed to LMP2 and LMP7 up-regulation in HTBE cells. Our data suggest that IP are induced during airway RV infection, which in turn may serve as an antiviral and anti-inflammatory mechanism.

Sign in / Sign up

Export Citation Format

Share Document