scholarly journals Selective dependence on IL-7 for antigen-specific CD8 T cell responses during airway influenza infection

2022 ◽  
Vol 12 (1) ◽  
Author(s):  
Abdalla Sheikh ◽  
Jennie Jackson ◽  
Hanjoo Brian Shim ◽  
Clement Yau ◽  
Jung Hee Seo ◽  
...  

AbstractInterleukin-7 (IL-7) is a cytokine known for its importance in T cell development and survival. How IL-7 shapes CD8 T cell responses during an acute viral infection is less understood. We had previously shown that IL-7 signaling deficient mice have reduced accumulation of influenza-specific CD8 T cells following influenza infection. We sought to determine whether IL-7 affects early CD8 T cell expansion in the mediastinal lymph node and effector function in the lungs. Using IL-7Rα signaling deficient mice, we show that IL-7 is required for a normal sized mediastinal lymph node and the early clonal expansion of influenza-specific CD8 T cells therein. We show that IL-7 plays a cell-intrinsic role in the accumulation of NP366–374 and PA224–233-specific CD8 T cells in the lymph node. We also found that IL-7 shapes terminal differentiation, degranulation and cytokine production to a greater extent in PA224–233-specific than NP366–374-specific CD8 T cells. We further demonstrate that IL-7 is induced in the lung tissue by viral infection and we characterize multiple cellular sources that contribute to IL-7 production. Our findings on IL-7 and its effects on lower respiratory diseases will be important for expanding the utility of therapeutics that are currently available.

2021 ◽  
Author(s):  
Abdalla Sheikh ◽  
Jennie Jackson ◽  
Hanjoo Brian Shim ◽  
Clement Yau ◽  
Jung Hee Seo ◽  
...  

AbstractAirborne diseases are the leading cause of infectious disease-related deaths in the world. In particular, the influenza virus activates a network of immune cells that leads to clearance or an overzealous response that can be fatal. Tight regulation of the cytokines that enable proper activation and function of immune cells is necessary to clear infections efficiently while minimizing damage to the host. Interleukin-7 (IL-7) is a cytokine known for its importance in T cell development and survival. How IL-7 shapes CD8 T cell responses during an acute viral infection is less understood. We had previously shown that IL-7 signaling deficient mice have reduced accumulation of influenza-specific CD8 T cells following infection. We sought to determine whether IL-7 affects early CD8 T cell expansion in the mediastinal lymph node and effector function in the lungs. Using IL-7Rα signaling deficient mice, we show that IL-7 is required for a normal sized mediastinal lymph node and the early clonal expansion of antigen-specific CD8 T cells therein. Bone marrow chimeric models and adoptive transfer of transgenic TCR CD8 T cells reveal a cell-intrinsic role for IL-7 in the accumulation of NP366–374 and PA224–233-specific CD8 T cells. We also found that IL-7 dictates terminal differentiation, degranulation and cytokine production in PA224–233-specific but not NP366–374-specific CD8 T cells. We further demonstrate that IL-7 is induced in the lung tissue by viral infection and we characterize multiple cellular sources that contribute to IL-7 production. Drugs that manipulate IL-7 signaling are currently under clinical trial for multiple conditions. Our findings on IL-7 and its effects on lower respiratory diseases will be important for expanding the utility of these therapeutics.Author SummaryInterleukin-7 plays an important role in development of immune cells such as lymphocytes. In recent years, its role in the immune system has been expanded beyond the development of immune cells to include revitalizing of lymphocytes during tumor and chronic viral response. We show here that IL-7 is required for accumulation and function of specialized lymphocytes in the lungs during an acute influenza infection.


Blood ◽  
2021 ◽  
Vol 138 (Supplement 1) ◽  
pp. 1720-1720
Author(s):  
Yongxia Wu ◽  
Linlu Tian ◽  
Corey Mealer ◽  
Hee-Jin Choi ◽  
Xue-Zhong Yu

Abstract The Provirus Integration sites for Moloney murine leukemia virus (Pim) kinases are a highly conserved family of serine/threonine kinases. The Pim kinase family is composed of three different isoforms, Pim1, Pim2, and Pim3, which have been studied extensively in tumorigenesis and as a potential therapeutic target in various cancers. We previously reported an unexpected role of Pim2 in negatively regulates T-cell responses to alloantigen and tumor (JCI, 2015, PMID: 29781812). However, the mechanisms by which Pim2 modulates T-cell responses remain largely undefined. In the current study, using genetic Pim2-deficient mouse, we demonstrated a key role of Pim2 in regulating T-cell hemostatic and anti-tumor responses in aging, hematopoietic cell transplantation (HCT), and antigen-specific adoptive T-cell therapy (ACT). We observed that Pim2 was critical for T cells to retain quiescent in aged mice, as thymic Treg development was impaired while effector T-cell differentiation in lymphoid organs, including Tc1/Th1, Tc17/Th17 and follicular helper T cells, was increased in Pim2-deficient mice, but not in Pim1/Pim3-deficient mice. Furthermore, Pim2-deficient mice were capable to completely eradicate syngeneic breast cancer (NT2.5) growth (Figure A). During antigen specific anti-tumor response, adoptively transferred Pim2 -/- CD8 T cells showed enhanced ability for controlling established NT2.5 breast cancer and B16 melanoma (Figure B, C). Mechanistically, loss of Pim2 promoted G1 to S phase cell-cycle progression while reduced apoptosis in CD8 T cells. Pim2 -/- CD8 T cells exhibited elevated effector cytokine production while maintained higher levels of CD62L expression, leading to superior effector function, persistence and anti-tumor activity. Reduced differentiation of exhausted and suppressive subsets were observed in Pim2 -/- CD8 T cells after being adoptively transferred in tumor-bearing mice. In addition, Pim2 deficiency was associated with a higher metabolic potential, reflected by increased glycolysis and oxidative phosphorylation, which was at least partially attributed to a decreased level of autophagy in Pim2 -/- CD8 T cells. To further evaluate the clinical translation potential, we applied a Pim2-specific inhibitor (JP11646) and found that blocking Pim2 improved graft-versus-leukemia activity after autologous HCT and also enhanced CD8 T-cell mediated anti-melanoma effects after ACT in mice (Figure B, C). Furthermore, blocking Pim2 using JP11646 promoted human CD8 T-cell response during polyclonal stimulation and enhanced expansion, effector function and tumor killing ability of human melanoma antigen-specific CD8 T cells (data not shown) and CD19 CAR-T cells (Figure D). Our work demonstrated that Pim2 is a potent and distinct regulator of differentiation and maintenance of T effector cells through modulating metabolism and autophagy. Specifically target Pim2 can serve as a novel strategy for improving cancer immunotherapy. Figure 1 Figure 1. Disclosures No relevant conflicts of interest to declare.


2020 ◽  
Vol 3 (Supplement_1) ◽  
pp. 139-140
Author(s):  
B K Hardman ◽  
L C Osborne

Abstract Background Human Norovirus infection is the most common viral cause of gastroenteritis globally and the second most reported viral infection in Canada after the common cold. Most infections are acute, symptomatic, and rapidly cleared but some cases persist asymptomatically or induce post-infectious irritable bowel syndrome. Despite the global burden of these infections, no vaccine to prevent disease exists nor is the mechanism for persistence understood. MNV-CW3 and MNV-CR6 are murine noroviruses which demonstrate distinct biological behaviors that correlate with differential quantity and quality of antiviral CD8+ T cell responses. MNV-CW3 causes acute systemic infections initiated in the small intestine and cleared by day 8 due to a robust antiviral CD8+ T cell response. In contrast, MNV-CR6 causes chronic infections localized to the colonic intestinal epithelium and induces fewer antiviral CD8+ T cells with reduced effector molecule expression. Aims This research interrogates the mechanisms underlying strain-specific differential antiviral CD8+ T cell responses. Methods At days 3, 4, 5 and 8 post-infection, the phenotype and quantity of adoptively transferred MNV specific CD8+ T cells in the spleen, mesenteric lymph node (MLN), and the small and large intestine are analyzed by flow cytometry. Concurrently, immunofluorescent microscopy is used to determine whether CD8+ T cells are broadly disseminated throughout the intestines or localize in acute clusters of antiviral response. Combining these complementary techniques provides novel insight into mechanisms governing intestinal antiviral T cell responses. Results Activated MNV-specific CD8 T cells first accumulate in the MLN following oral infection with both MNV-CW3 and CR6, suggesting this is the site of immune activation. Supporting this hypothesis, preliminary data indicates that preventing T cell egress from activation sites by treatment with the S1PR1 agonist FTY720 leads to an enrichment of activated CD8+ T cells in the MLN following CW3 infection. Notably, the earliest stages of CD8+ T cell activation to CR6 infection is delayed compared to that elicited by CW3. Furthermore, at the peak of CD8+ T cell expansion (day 8 post-infection), CR6-elicited CD8+ T cells preferentially develop into short-lived effector populations rather than memory precursor populations. Conclusions These data reveal previously unknown differences in early events in CD8+ T cell activation following infection with two highly related viral strains that correlate with long-lasting effects on T cell differentiation and function. We are currently investigating the hypothesis that MNV-CW3 and CR6 may induce activation of distinct populations of, or pathways in, APC populations that would drive these differences. These results may have broad impacts on our understanding of how non-latent, chronic viral infections persist within a host. Funding Agencies CIHR


2005 ◽  
Vol 201 (7) ◽  
pp. 1053-1059 ◽  
Author(s):  
Jason K. Whitmire ◽  
Joyce T. Tan ◽  
J. Lindsay Whitton

Interferon-γ (IFNγ) is important in regulating the adaptive immune response, and most current evidence suggests that it exerts a negative (proapoptotic) effect on CD8+ T cell responses. We have developed a novel technique of dual adoptive transfer, which allowed us to precisely compare, in normal mice, the in vivo antiviral responses of two T cell populations that differ only in their expression of the IFNγ receptor. We use this technique to show that, contrary to expectations, IFNγ strongly stimulates the development of CD8+ T cell responses during an acute viral infection. The stimulatory effect is abrogated in T cells lacking the IFNγ receptor, indicating that the cytokine acts directly upon CD8+ T cells to increase their abundance during acute viral infection.


2005 ◽  
Vol 79 (15) ◽  
pp. 9419-9429 ◽  
Author(s):  
Nicole E. Miller ◽  
Jennifer R. Bonczyk ◽  
Yumi Nakayama ◽  
M. Suresh

ABSTRACT Although it is well documented that CD8 T cells play a critical role in controlling chronic viral infections, the mechanisms underlying the regulation of CD8 T-cell responses are not well understood. Using the mouse model of an acute and chronic lymphocytic choriomeningitis virus (LCMV) infection, we have examined the relative importance of peripheral T cells and thymic emigrants in the elicitation and maintenance of CD8 T-cell responses. Virus-specific CD8 T-cell responses were compared between mice that were either sham thymectomized or thymectomized (Thx) at ∼6 weeks of age. In an acute LCMV infection, thymic deficiency did not affect either the primary expansion of CD8 T cells or the proliferative renewal and maintenance of virus-specific lymphoid and nonlymphoid memory CD8 T cells. Following a chronic LCMV infection, in Thx mice, although the initial expansion of CD8 T cells was normal, the contraction phase of the CD8 T-cell response was exaggerated, which led to a transient but striking CD8 T-cell deficit on day 30 postinfection. However, the virus-specific CD8 T-cell response in Thx mice rebounded quickly and was maintained at normal levels thereafter, which indicated that the peripheral T-cell repertoire is quite robust and capable of sustaining an effective CD8 T-cell response in the absence of thymic output during a chronic LCMV infection. Taken together, these findings should further our understanding of the regulation of CD8 T-cell homeostasis in acute and chronic viral infections and might have implications in the development of immunotherapy.


2006 ◽  
Vol 81 (2) ◽  
pp. 934-944 ◽  
Author(s):  
Markus Cornberg ◽  
Brian S. Sheridan ◽  
Frances M. Saccoccio ◽  
Michael A. Brehm ◽  
Liisa K. Selin

ABSTRACT Live vaccinia virus (VV) vaccination has been highly successful in eradicating smallpox. However, the mechanisms of immunity involved in mediating this protective effect are still poorly understood, and the roles of CD8 T-cell responses in primary and secondary VV infections are not clearly identified. By applying the concept of molecular mimicry to identify potential CD8 T-cell epitopes that stimulate cross-reactive T cells specific to lymphocytic choriomeningitis virus (LCMV) and VV, we identified after screening only 115 peptides two VV-specific immunogenic epitopes that mediated protective immunity against VV. An immunodominant epitope, VV-e7r130, did not generate cross-reactive T-cell responses to LCMV, and a subdominant epitope, VV-a11r198, did generate cross-reactive responses to LCMV. Infection with VV induced strong epitope-specific responses which were stable into long-term memory and peaked at the time virus was cleared, consistent with CD8 T cells assisting in the control of VV. Two different approaches, direct adoptive transfer of VV-e7r-specific CD8 T cells and prior immunization with a VV-e7r-expressing ubiquitinated minigene, demonstrated that memory CD8 T cells alone could play a significant role in protective immunity against VV. These studies suggest that exploiting cross-reactive responses between viruses may be a useful tool to complement existing technology in predicting immunogenic epitopes to large viruses, such as VV, leading to a better understanding of the role CD8 T cells play during these viral infections.


2021 ◽  
Author(s):  
Leonardo Estrada ◽  
Didem Agac Cobanoglu ◽  
Aaron Wise ◽  
Robert Maples ◽  
Murat Can Cobanoglu ◽  
...  

Viral infections drive the expansion and differentiation of responding CD8+ T cells into variegated populations of cytolytic effector and memory cells. While pro-inflammatory cytokines and cell surface immune receptors play a key role in guiding T cell responses to infection, T cells are also markedly influenced by neurotransmitters. Norepinephrine is a key sympathetic neurotransmitter, which acts to suppress CD8 + T cell cytokine secretion and lytic activity by signaling through the beta2-adrenergic receptor (ADRB2). Although ADRB2 signaling is considered generally immunosuppressive, its role in regulating differentiation of effector T cells in response to infection has not been investigated. Using an adoptive transfer approach, we compared the expansion and differentiation of wild type (WT) to Adrb2-/- CD8 + T cells throughout the primary response to vesicular stomatitis virus (VSV) infection in vivo. We measured the dynamic changes in transcriptome profiles of antigen-specific CD8 + T cells as they responded to VSV. Within the first 7 days of infection, WT cells out-paced the expansion of Adrb2-/- cells, which correlated with reduced expression of IL-2 and the IL-2Ralpha; in the absence of ADRB2. RNASeq analysis identified over 300 differentially expressed genes that were both temporally regulated following infection and selectively regulated in WT vs Adrb2-/- cells. These genes contributed to major transcriptional pathways including cytokine receptor activation, signaling in cancer, immune deficiency, and neurotransmitter pathways. By parsing genes within groups that were either induced or repressed over time in response to infection, we identified three main branches of genes that were differentially regulated by the ADRB2. These gene sets were predicted to be regulated by specific transcription factors involved in effector T cell development, such as Tbx21 and Eomes. Collectively, these data demonstrate a significant role for ADRB2 signaling in regulating key transcriptional pathways during CD8 + T cells responses to infection that may dramatically impact their functional capabilities and downstream memory cell development.


eLife ◽  
2017 ◽  
Vol 6 ◽  
Author(s):  
Alexandria C Wells ◽  
Keith A Daniels ◽  
Constance C Angelou ◽  
Eric Fagerberg ◽  
Amy S Burnside ◽  
...  

The differentiation of naive CD8 T cells into effector cytotoxic T lymphocytes upon antigen stimulation is necessary for successful antiviral, and antitumor immune responses. Here, using a mouse model, we describe a dual role for the let-7 microRNAs in the regulation of CD8 T cell responses, where maintenance of the naive phenotype in CD8 T cells requires high levels of let-7 expression, while generation of cytotoxic T lymphocytes depends upon T cell receptor-mediated let-7 downregulation. Decrease of let-7 expression in activated T cells enhances clonal expansion and the acquisition of effector function through derepression of the let-7 targets, including Myc and Eomesodermin. Ultimately, we have identified a novel let-7-mediated mechanism, which acts as a molecular brake controlling the magnitude of CD8 T cell responses.


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