Abstract 113: Regulatory T Cells Contribute to Sexual Dimorphic Outcomes After Acute Ischemic Brain Injury

Introduction: The contribution of CD4 + Foxp3 + regulatory T cells (Treg) to acute stroke outcomes has been controversially reported in young male murine models of stroke, their effects in female stroke mice, however, are not characterized. This study explored the sexual dimorphisms in Treg and its contribution to acute stroke outcomes. Methods: Cerebral ischemia was induced by 60 min tMCAO in male or female (Young: 10-week, aged: 15-month) wild type (WT) mice and DTR mice expressing the diphtheria toxin (DT) receptor under the control of Foxp3 promoter. Tregs depletion was achieved by DT injection in DTR mice for 3 days prior to tMCAO. Infarct volume, sensorimotor functions and peripheral immune cell populations were assessed up to 5d after stroke. For RNA sequencing analysis, Tregs were sorted from blood of male or female DTR mice at 5d after sham or tMCAO surgery. Results: Young Treg competent (WT mice or DTR mice without DT) female mice exhibited significantly reduced infarct volume, as assessed by MRI T2 scanning and MAP2 staining, and greatly improved sensorimotor functions (rotarod test and adhesive removal test) compared to age- and genotype-matched male mice (n=8/group) 5d after tMCAO. Treg depletion deprived the neuroprotection in young female, while showed no significant effect on young male or aged female mice (n=8/group). RNA-seq analysis showed that IFN-γ signaling was downregulated in female Treg while upregulated in male Treg, suggesting a sexual difference in Treg-mediated immune response after stroke. Flow cytometry revealed ameliorated immune cell activation in blood and brain in female vs male mice 5d after stroke. Furthermore, Treg were isolated from young female, young male, aged female or female mice subjected to ovariectomy, and adoptively transferred (1 million cell/animal, iv) to young male mice 1 hour after tMCAO. Only young female Treg significantly reduced the infarct volume and improved sensorimotor functions compared to other treatment groups (n=7-8/group). Conclusion: Treg contribute to the neuroprotection in young female vs male in an age- and hormone-dependent manner. Transcriptomic analysis uncovered sexual differences in an IFN-γ centered regulatory pathways in Tregs, which keep post-stroke immune responses in check.

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The Influence of Age, Sex and Exercise on Autophagy, Mitophagy and Lysosome Biogenesis in Skeletal Muscle

10.21203/rs.3.rs-1104184/v1 ◽

2021 ◽

Author(s):

Matthew Triolo ◽

Ashley N. Oliveria ◽

Rita Kumari ◽

David A. Hood

Keyword(s):

Skeletal Muscle ◽

Acute Exercise ◽

Young Male ◽

Young Female ◽

The Other ◽

Male Mice ◽

Mitochondrial Content ◽

Female Mice ◽

Biological Sex ◽

Lysosome Biogenesis

Abstract BackgroundAging decreases skeletal muscle mass and quality. Maintenance of healthy muscle is regulated by a balance between protein and organellar synthesis and their degradation. The autophagy lysosome system is responsible for the selective degradation of protein aggregates and organelles, such as mitochondria (i.e., mitophagy). Little data exist on the independent and combined influence of age, biological sex and exercise on the autophagy system and lysosome biogenesis. The purpose of this study was to characterize sex differences in autophagy and lysosome biogenesis in young and aged muscle, and to determine if acute exercise influences these processes.MethodsYoung (4-6 months) and aged (22-24 months) male and female mice, were assigned to a sedentary, or an acute exercise group. Mitochondrial content, the autophagy-lysosome system and mitophagy were measured via protein analysis. A Tfeb-promoter-construct was utilized to examine Tfeb transcription, and nuclear-cytosolic fractions allowed us to examine Tfeb localization in sedentary and exercised muscle with age and sex.ResultsOur results indicate that female mice, both young and old, had more mitochondrial protein than age-matched males, and mitochondrial content was only reduced with age in the male cohort. Although young female mice had a greater abundance of autophagy, mitophagy and lysosome proteins than young males, we measured increases with age irrespective of sex. Interestingly, young sedentary female mice had indices of greater autophagosomal turnover than male counterparts. Exhaustive exercise was able to stimulate autophagic clearance in young male mice, but not in the other groups. Similarly, nuclear Tfeb protein was enhanced to a greater extent in young male than in young female mice following exercise, but no changes were observed in aged mice. Finally, Tfeb-promoter activity was upregulated following exercise in both young and aged muscle.ConclusionsThe present study demonstrates that biological sex influences mitochondrial homeostasis, the autophagy-lysosome system and mitophagy in skeletal muscle with age. Further, our data suggest that young male mice have a more profound ability to activate these processes with exercise than in the other groups. Ultimately, this may contribute to a greater remodeling of muscle in response to exercise training in males.

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Sexual Dimorphism in the Control of Amebic Liver Abscess in a Mouse Model of Disease

Infection and Immunity ◽

10.1128/iai.74.1.118-124.2006 ◽

2006 ◽

Vol 74 (1) ◽

pp. 118-124 ◽

Cited By ~ 66

Author(s):

Hannelore Lotter ◽

Thomas Jacobs ◽

Iris Gaworski ◽

Egbert Tannich

Keyword(s):

T Cells ◽

Sexual Dimorphism ◽

Liver Abscess ◽

Cytokine Production ◽

Experimental Studies ◽

Nkt Cells ◽

Amebic Liver Abscess ◽

Male Mice ◽

Female Mice ◽

Ifn Γ

ABSTRACT Amebic liver abscess (ALA) is the most common extraintestinal manifestation of human infection by the enteric protozoan parasite Entamoeba histolytica. In contrast to intestinal infection, ALA greatly predominates in males but is rare in females. Since humans are the only relevant host for E. histolytica, experimental studies concerning this sexual dimorphism have been hampered by the lack of a suitable animal model. By serial liver passage of cultured E. histolytica trophozoites in gerbils and mice, we generated amebae which reproducibly induce ALA in C57BL/6 mice. Interestingly, all animals developed ALA, but the time courses of abscess formation differed significantly between the genders. Female mice were able to clear the infection within 3 days, whereas in male mice the parasite could be recovered for at least 14 days. Accordingly, male mice showed a prolonged time of recovery from ALA. Immunohistology of abscesses revealed that polymorphonuclear leukocytes and macrophages were the dominant infiltrates, but in addition, γ,δ-T cells, NK cells, and natural killer T (NKT) cells were also present at early times during abscess development, whereas conventional α,β-T cells appeared later, when female mice had already cleared the parasite. Interestingly, male and female mice differed in early cytokine production in response to ameba infection. Enzyme-linked immunospot assays performed with spleen cells of infected animals revealed significantly higher numbers of interleukin-4-producing cells in male mice but significantly higher numbers of gamma interferon (IFN-γ)-producing cells in female mice. Early IFN-γ production and the presence of functional NKT cells were found to be important for the control of hepatic amebiasis as application of an IFN-γ-neutralizing monoclonal antibody or the use of NKT knockout mice (Vα14iNKT, Jα 18−/−) dramatically increased the size of ALA in female mice. In addition, E. histolytica trophozoites could be reisolated from liver abscesses of Jα18−/− mice on day 7 postinfection, when wild-type mice had already cleared the parasite. These data suggest that the sexual dimorphism in the control of ALA is due to gender-specific differences in early cytokine production mediated at least in part by NKT cells in response to E. histolytica infection of the liver.

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Dendritic cells and regulatory T cells expressing CCR4 provide resistance to coxsackievirus B5-induced pancreatitis

Scientific Reports ◽

10.1038/s41598-019-51311-9 ◽

2019 ◽

Vol 9 (1) ◽

Author(s):

Marcela C. S. Françozo ◽

Frederico R. C. Costa ◽

Isabel C. Guerra-Gomes ◽

João S. Silva ◽

Renata Sesti-Costa

Keyword(s):

T Cells ◽

Regulatory T Cells ◽

T Lymphocyte ◽

Immune Cell ◽

Lymphocyte Activation ◽

Cellular Migration ◽

T Lymphocyte Activation ◽

Pancreatic Lymph Nodes ◽

Ifn Γ ◽

Immune Cell Migration

Abstract Type B coxsackieviruses (CVB) are enteroviruses responsible for a common infectious myocarditis and pancreatitis. DCs and regulatory T cells (Tregs) are key players in controlling virus replication and regulating the immune response and tissue damage, respectively. However, the mechanisms underlying cellular migration to target tissues remain unclear. In the present study, we found that CVB5 infection induced CCL17 production and controlled the migration of CCR4+ DCs and CCR4+ Tregs to the pancreatic lymph nodes (pLN). CVB5 infection of CCR4−/− mice reduced the migration of the CD8α+ DC subset and reduced DC activation and production of IFN-β and IL-12. Consequently, CCR4−/− mice presented decreased IFN-γ-producing CD4+ and CD8+ T cells, an increased viral load and more severe pancreatitis. In addition, CCR4−/− mice had impaired Treg accumulation in pLN as well as increased T lymphocyte activation. Adoptive transfer of CCR4+ Tregs but not CCR4− Tregs was able to regulate T lymphocyte activation upon CVB5 infection. The present data reveal a previously unknown role for CCR4 in coordinating immune cell migration to CVB-infected tissues and in controlling subsequent pancreatitis. These new insights may contribute to the design of future therapies for acute and chronic infection of non-polio enteroviruses.

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MiR-146a regulates regulatory T cells to suppress heart transplant rejection in mice

Cell Death Discovery ◽

10.1038/s41420-021-00534-9 ◽

2021 ◽

Vol 7 (1) ◽

Author(s):

Jian Lu ◽

Weiwei Wang ◽

Peiyuan Li ◽

Xiaodong Wang ◽

Chao Gao ◽

...

Keyword(s):

T Cells ◽

Regulatory T Cells ◽

Heart Transplant ◽

Transplant Rejection ◽

Mouse Heart ◽

Allograft Survival ◽

Treg Function ◽

Ifn Γ ◽

Heart Transplant Rejection

AbstractRegulatory T cells (Tregs), which characteristically express forkhead box protein 3 (Foxp3), are essential for the induction of immune tolerance. Here, we investigated microRNA-146a (miR-146a), a miRNA that is widely expressed in Tregs and closely related to their homeostasis and function, with the aim of enhancing the function of Tregs by regulating miR-146a and then suppressing transplant rejection. The effect of the absence of miR-146a on Treg function in the presence or absence of rapamycin was detected in both a mouse heart transplantation model and cell co-cultures in vitro. The absence of miR-146a exerted a mild tissue-protective effect by transiently prolonging allograft survival and reducing the infiltration of CD4+ and CD8+ T cells into the allografts. Meanwhile, the absence of miR-146a increased Treg expansion but impaired the ability of Tregs to restrict T helper cell type 1 (Th1) responses. A miR-146a deficiency combined with interferon (IFN)-γ blockade repaired the impaired Treg function, further prolonged allograft survival, and alleviated rejection. Importantly, miR-146a regulated Tregs mainly through the IFN-γ/signal transducer and activator of transcription (STAT) 1 pathway, which is implicated in Treg function to inhibit Th1 responses. Our data suggest miR-146a controls a specific aspect of Treg function, and modulation of miR-146a may enhance Treg efficacy in alleviating heart transplant rejection in mice.

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Infiltration of a Mesothelioma by IFN-γ-Producing Cells and Tumor Rejection after Depletion of Regulatory T Cells

The Journal of Immunology ◽

10.4049/jimmunol.178.7.4089 ◽

2007 ◽

Vol 178 (7) ◽

pp. 4089-4096 ◽

Cited By ~ 26

Author(s):

Geordie Rudge ◽

Simon P. Barrett ◽

Bernadette Scott ◽

Ian R. van Driel

Keyword(s):

T Cells ◽

Regulatory T Cells ◽

Tumor Rejection ◽

Ifn Γ

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CD38 Correlates with an Immunosuppressive Treg Phenotype in Lupus-Prone Mice

International Journal of Molecular Sciences ◽

10.3390/ijms222111977 ◽

2021 ◽

Vol 22 (21) ◽

pp. 11977

Author(s):

Jocelyn C. Pérez-Lara ◽

Enrique Espinosa ◽

Leopoldo Santos-Argumedo ◽

Héctor Romero-Ramírez ◽

Gabriela López-Herrera ◽

...

Keyword(s):

T Cells ◽

Regulatory T Cells ◽

Immune Activation ◽

Lupus Erythematosus ◽

Clinical Signs ◽

Foxp3 Expression ◽

Cell Receptor ◽

Treg Cells ◽

Transmembrane Glycoprotein ◽

Ifn Γ

CD38 is a transmembrane glycoprotein expressed by T-cells. It has been reported that patients with systemic lupus erythematosus (SLE) showed increased CD38+CD25+ T-cells correlating with immune activation and clinical signs. Contrariwise, CD38 deficiency in murine models has shown enhanced autoimmunity development. Recent studies have suggested that CD38+ regulatory T-cells are more suppressive than CD38− regulatory T-cells. Thus, we have suggested that CD38 overexpression in SLE patients could play a role in regulating immune activation cells instead of enhancing it. This study found a correlation between CD38 with FoxP3 expression and immunosuppressive molecules (CD69, IL-10, CTLA-4, and PD-1) in T-cells from lupus-prone mice (B6.MRL-Faslpr/J). Additionally, B6.MRL-Faslpr/J mice showed a decreased proportion of CD38+ Treg cells regarding wild-type mice (WT). Furthermore, Regulatory T-Cells (Treg cells) from CD38-/- mice showed impairment in expressing immunosuppressive molecules and proliferation after stimulation through the T-cell receptor (TCR). Finally, we demonstrated an increased ratio of IFN-γ/IL-10 secretion in CD38-/- splenocytes stimulated with anti-CD3 compared with the WT. Altogether, our data suggest that CD38 represents an element in maintaining activated and proliferative Treg cells. Consequently, CD38 could have a crucial role in immune tolerance, preventing SLE development through Treg cells.

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Interleukin-30 Suppresses Not Only CD4+ T Cells but Also Regulatory T Cells in Murine Primary Biliary Cholangitis

Biomedicines ◽

10.3390/biomedicines9081031 ◽

2021 ◽

Vol 9 (8) ◽

pp. 1031

Author(s):

Hung-Wen Chen ◽

Chia-I. Lin ◽

Ya-Hui Chuang

Keyword(s):

T Cells ◽

Regulatory T Cells ◽

Cd4 T Cells ◽

Primary Biliary Cholangitis ◽

Autoimmune Cholangitis ◽

Liver Inflammation ◽

Adeno Associated Virus ◽

Cytokines And Chemokines ◽

Ifn Γ

Primary biliary cholangitis (PBC) is a chronic liver autoimmune disease with augmented T helper (Th) 1 and corresponding cytokine IFN-γ immune responses. Using 2-octynoic acid (2-OA) coupled to OVA (2-OA-OVA)-induced mouse models of autoimmune cholangitis (inducible chemical xenobiotic models of PBC), our previous study demonstrated that overexpression of IFN-γ in the model mice enhanced liver inflammation upon disease initiation, but subsequently led to the suppression of chronic inflammation with an increase in interleukin-30 (IL-30) levels. In this study, we investigated whether IL-30 had an immunosuppressive function and whether it could be part of an immune therapeutic regimen for PBC, by treating model mice with murine IL-30-expressing recombinant adeno-associated virus (AAV-mIL-30). We first defined the effects of AAV-mIL-30 in vivo by administering it to a well-known concanavalin A (ConA)-induced hepatitis model of mice and found that AAV-mIL-30 reduced the numbers of activated CD25+CD4+ T cells and the levels of serum IFN-γ and IL-12. In autoimmune cholangitis, decreased numbers of activated CD4+ T cells and Foxp3+ regulatory T cells were noted in the mice treated with AAV-mIL-30 at 3 weeks after the 2-OA-OVA immunization. Treatment with IL-30 did not change the features of autoimmune cholangitis including autoantibodies, cell infiltration, and collagen deposition in the liver at 11 weeks of examination. However, increased levels of cytokines and chemokines were observed. These results suggest that IL-30 suppresses not only CD4+ T cells but also regulatory T cells. Additionally, the administration of IL-30 did not suppress liver inflammation in the murine model of PBC.

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Cytolethal Distending Toxin Is Essential for Helicobacter hepaticus Colonization in Outbred Swiss Webster Mice

Infection and Immunity ◽

10.1128/iai.73.6.3559-3567.2005 ◽

2005 ◽

Vol 73 (6) ◽

pp. 3559-3567 ◽

Cited By ~ 68

Author(s):

Zhongming Ge ◽

Yan Feng ◽

Mark T. Whary ◽

Prashant R. Nambiar ◽

Shilu Xu ◽

...

Keyword(s):

Mrna Level ◽

Interleukin 10 ◽

Mouse Strains ◽

Cytolethal Distending Toxin ◽

Mrna Levels ◽

Helicobacter Hepaticus ◽

Male Mice ◽

Susceptible Mouse ◽

Female Mice ◽

Ifn Γ

ABSTRACT Helicobacter hepaticus, which induces chronic hepatitis and typhlocolitis in susceptible mouse strains, produces a cytolethal distending toxin (CDT) consisting of CdtA, CdtB, and CdtC. A cdtB-deficient H. hepaticus isogenic mutant (HhcdtBm7) was generated and characterized for colonization parameters in four intestinal regions (jejunum, ileum, cecum, and colon) of outbred Swiss Webster (SW) mice. Inactivation of the cdtB gene abolished the ability of HhcdtBm7 to colonize female mice at both 8 and 16 weeks postinfection (wpi), whereas HhcdtBm7 colonized all of four intestinal regions of three of five males at 8 wpi and then was eliminated by 16 wpi. Wild-type (WT) H. hepaticus was detected in the corresponding intestinal regions of both male and female mice at 8 and 16 wpi; however, colonization levels of WT H. hepaticus in the cecum and colon of male mice were approximately 1,000-fold higher than in females (P < 0.0079) at 16 wpi. Infection with WT H. hepaticus, but not HhcdtBm7, at 8 wpi was associated with significantly increased mRNA level of ileal and cecal gamma interferon (IFN-γ) in females (P < 0.016 and 0.031 between WT H. hepaticus-infected and sham-dosed females, respectively). In contrast, the mRNA levels of IFN-γ were significantly higher in the colon (P < 0.0079) and trended to be higher in the cecum (P < 0.15) in the HhcdtBm7-colonized male mice versus the sham-dosed controls at 8 wpi. In addition, mRNA levels of ileal IFN-γ were significantly higher in the control females than males at 8 wpi (P < 0.016). There were significantly higher Th1-associated immunoglobulin G2a (IgG2a), Th2-associated IgG1 and mucosal IgA (P < 0.002, 0.002, 0.002, respectively) responses in the mice infected with WT H. hepaticus when compared to HhcdtBm7 at 16 wpi. Colonic interleukin-10 (IL-10) expressions at 16 wpi were significantly lower in both female and male mice colonized by WT H. hepaticus or in males transiently colonized through 8 wpi by HhcdtBm7 versus control mice (P < 0.0159). These lines of evidence indicate that (i) H. hepaticus CDT plays a crucial role in the persistent colonization of H. hepaticus in SW mice; (ii) SW female mice are more resistant to H. hepaticus colonization than male mice; (iii) there was persistent colonization of WT H. hepaticus in cecum, colon, and jejunum but only transient colonization of H. hepaticus in the ileum of female mice; (iv) H. hepaticus colonization was associated with down-regulation of colonic IL-10 production.

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O4 Mechanisms of lung cancer hyper-progression promoted by PD-1 immune checkpoint blockade

Journal for ImmunoTherapy of Cancer ◽

10.1136/jitc-2020-itoc7.9 ◽

2020 ◽

Vol 8 (Suppl 2) ◽

pp. A5.1-A5

Author(s):

A Martinez-Usatorre ◽

E Kadioglu ◽

C Cianciaruso ◽

B Torchia ◽

J Faget ◽

...

Keyword(s):

Lung Cancer ◽

T Cells ◽

Regulatory T Cells ◽

Immune Checkpoint ◽

Immune Cell ◽

Immune Checkpoint Blockade ◽

Genetically Engineered ◽

Checkpoint Blockade ◽

Therapeutic Benefits ◽

Angiopoietin 2

BackgroundImmune checkpoint blockade (ICB) with antibodies against PD-1 or PD-L1 may provide therapeutic benefits in patients with non-small cell lung cancer (NSCLC). However, most tumours are resistant and cases of disease hyper-progression have also been reported.Materials and MethodsGenetically engineered mouse models of KrasG12Dp53null NSCLC were treated with cisplatin along with antibodies against angiopoietin-2/VEGFA, PD-1 and CSF1R. Tumour growth was monitored by micro-computed tomography and the tumour vasculature and immune cell infiltrates were assessed by immunofluorescence staining and flow cytometry.ResultsCombined angiopoietin-2/VEGFA blockade by a bispecific antibody (A2V) modulated the vasculature and abated immunosuppressive macrophages while increasing CD8+effector T cells in the tumours, achieving disease stabilization comparable or superior to cisplatin-based chemotherapy. However, these immunological responses were unexpectedly limited by the addition of a PD-1 antibody, which paradoxically enhanced progression of a fraction of the tumours through a mechanism involving regulatory T cells and macrophages. Elimination of tumour-associated macrophages with a CSF1R-blocking antibody induced NSCLC regression in combination with PD-1 blockade and cisplatin.ConclusionsThe immune cell composition of the tumour determines the outcome of PD-1 blockade. In NSCLC, high infiltration of regulatory T cells and immunosuppressive macrophages may account for tumour hyper-progression upon ICB.Disclosure InformationA. Martinez-Usatorre: None. E. Kadioglu: None. C. Cianciaruso: None. B. Torchia: None. J. Faget: None. E. Meylan: None. M. Schmittnaegel: None. I. Keklikoglou: None. M. De Palma: None.

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