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Song W, Postoak JL, Wu L, Van Kaer L. PIK3C3/VPS34 keeps body fats healthy. Autophagy 2023; 19:2398-2400. [PMID: 36629752 PMCID: PMC10351436 DOI: 10.1080/15548627.2023.2166275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2023] [Revised: 01/04/2023] [Accepted: 01/04/2023] [Indexed: 01/12/2023] Open
Abstract
Adipose tissue, or body fat, plays a critical role in the maintenance of health and the development of metabolic diseases. The pathological expansion of adipose tissue during obesity and the pathological reduction of adipose tissue during lipodystrophy can lead to a similar array of metabolic diseases that include diabetes, but mechanisms remain to be fully defined. In our recent studies, we explored the contribution of the lipid kinase PIK3C3/VPS34 to adipose tissue health and metabolic disease. We found that adipocyte-specific PIK3C3/VPS34 deficiency causes defects in the differentiation, survival and functional properties of adipocytes, resulting in reduced adipose tissue mass, altered blood lipid levels, fatty liver disease, diabetes, and defective body temperature control. These abnormalities mirror those observed in patients with lipodystrophy. These findings identify adipocyte PIK3C3/VPS34 as a potential target for therapeutic intervention in metabolic diseases.
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Affiliation(s)
- Wenqiang Song
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - J. Luke Postoak
- Current address: Department of Pathology and Immunology, Washington University in St. Louis, School of Medicine, St. Louis, MO, USA
| | - Lan Wu
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Luc Van Kaer
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN, USA
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2
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Postoak JL, Song W, Wu L, Van Kaer L. PIK3C3/VPS34 helps school T cells in the thymus. Autophagy 2023; 19:1890-1892. [PMID: 36394336 PMCID: PMC10262775 DOI: 10.1080/15548627.2022.2148428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Revised: 11/11/2022] [Accepted: 11/11/2022] [Indexed: 11/18/2022] Open
Abstract
The development of a broad repertoire of T cells in the immune system requires interaction of T cell receptors expressed by immature T cells with peptide/major histocompatibility complexes (MHCs) displayed by specialized epithelial cells in the thymus, in a process called T cell positive selection. Thymic epithelial cells (TECs) display unique antigen processing machinery which shapes the collection of self-peptides that drive positive selection. In our recent studies, we explored the contribution of the lipid kinase PIK3C3/VPS34 to the generation of positively selecting peptides in TECs. We found that TEC-specific PIK3C3/VPS34 facilitates the positive selection of CD4 but not CD8 T lineage cells, in a mechanism independent of its role in canonical macroautophagy/autophagy. Instead, we propose that PIK3C3/VPS34 alters vesicle trafficking in TECs that modulates lysosomal protease activity which, in turn, controls the generation of MHC class II-presented peptides optimized for positive selection of CD4 T cells.
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Affiliation(s)
- J. Luke Postoak
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - Wenqiang Song
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - Lan Wu
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - Luc Van Kaer
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
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3
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Song W, Postoak JL, Yang G, Guo X, Pua HH, Bader J, Rathmell JC, Kobayashi H, Haase VH, Leaptrot KL, Schrimpe-Rutledge AC, Sherrod SD, McLean JA, Zhang J, Wu L, Van Kaer L. Lipid kinase PIK3C3 maintains healthy brown and white adipose tissues to prevent metabolic diseases. Proc Natl Acad Sci U S A 2023; 120:e2214874120. [PMID: 36574710 PMCID: PMC9910429 DOI: 10.1073/pnas.2214874120] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Accepted: 09/29/2022] [Indexed: 12/28/2022] Open
Abstract
Adequate mass and function of adipose tissues (ATs) play essential roles in preventing metabolic perturbations. The pathological reduction of ATs in lipodystrophy leads to an array of metabolic diseases. Understanding the underlying mechanisms may benefit the development of effective therapies. Several cellular processes, including autophagy and vesicle trafficking, function collectively to maintain AT homeostasis. Here, we investigated the impact of adipocyte-specific deletion of the lipid kinase phosphatidylinositol 3-kinase catalytic subunit type 3 (PIK3C3) on AT homeostasis and systemic metabolism in mice. We report that PIK3C3 functions in all ATs and that its absence disturbs adipocyte autophagy and hinders adipocyte differentiation, survival, and function with differential effects on brown and white ATs. These abnormalities cause loss of white ATs, whitening followed by loss of brown ATs, and impaired "browning" of white ATs. Consequently, mice exhibit compromised thermogenic capacity and develop dyslipidemia, hepatic steatosis, insulin resistance, and type 2 diabetes. While these effects of PIK3C3 largely contrast previous findings with the autophagy-related (ATG) protein ATG7 in adipocytes, mice with a combined deficiency in both factors reveal a dominant role of the PIK3C3-deficient phenotype. We have also found that dietary lipid excess exacerbates AT pathologies caused by PIK3C3 deficiency. Surprisingly, glucose tolerance is spared in adipocyte-specific PIK3C3-deficient mice, a phenotype that is more evident during dietary lipid excess. These findings reveal a crucial yet complex role for PIK3C3 in ATs, with potential therapeutic implications.
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Affiliation(s)
- Wenqiang Song
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN37232
| | - J. Luke Postoak
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN37232
| | - Guan Yang
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN37232
- Department of Infectious Diseases and Public Health, City University of Hong Kong, Kowloon Tong999077, Hong Kong
| | - Xingyi Guo
- Division of Epidemiology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN37232
- Department of Biomedical Informatics, Vanderbilt University Medical Center, Nashville, TN37232
| | - Heather H. Pua
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN37232
| | - Jackie Bader
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN37232
| | - Jeffrey C. Rathmell
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN37232
| | - Hanako Kobayashi
- Division of Nephrology and Hypertension, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN37232
- The Vanderbilt O’Brien Kidney Center, Vanderbilt University Medical Center, Nashville, TN37232
- Medical and Research Services, Department of Veterans Affairs Hospital, Tennessee Valley Healthcare System, Nashville, TN37212
| | - Volker H. Haase
- Division of Nephrology and Hypertension, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN37232
- The Vanderbilt O’Brien Kidney Center, Vanderbilt University Medical Center, Nashville, TN37232
- Medical and Research Services, Department of Veterans Affairs Hospital, Tennessee Valley Healthcare System, Nashville, TN37212
| | - Katrina L. Leaptrot
- Center for Innovative Technology, Vanderbilt University, Nashville, TN37232
- Department of Chemistry, Vanderbilt University, Nashville, TN37232
| | - Alexandra C. Schrimpe-Rutledge
- Center for Innovative Technology, Vanderbilt University, Nashville, TN37232
- Department of Chemistry, Vanderbilt University, Nashville, TN37232
| | - Stacy D. Sherrod
- Center for Innovative Technology, Vanderbilt University, Nashville, TN37232
- Department of Chemistry, Vanderbilt University, Nashville, TN37232
| | - John A. McLean
- Center for Innovative Technology, Vanderbilt University, Nashville, TN37232
- Department of Chemistry, Vanderbilt University, Nashville, TN37232
| | - Jianhua Zhang
- Department of Pathology, University of Alabama at Birmingham, Birmingham, AL35294
- Birmingham Veterans Affairs Medical Center, Birmingham, AL35233
| | - Lan Wu
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN37232
| | - Luc Van Kaer
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN37232
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4
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Postoak JL, Song W, Yang G, Guo X, Xiao S, Saffold CE, Zhang J, Joyce S, Manley NR, Wu L, Van Kaer L. Thymic epithelial cells require lipid kinase Vps34 for CD4 but not CD8 T cell selection. J Exp Med 2022; 219:e20212554. [PMID: 35997680 PMCID: PMC9402993 DOI: 10.1084/jem.20212554] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Revised: 06/22/2022] [Accepted: 08/03/2022] [Indexed: 11/04/2022] Open
Abstract
The generation of a functional, self-tolerant T cell receptor (TCR) repertoire depends on interactions between developing thymocytes and antigen-presenting thymic epithelial cells (TECs). Cortical TECs (cTECs) rely on unique antigen-processing machinery to generate self-peptides specialized for T cell positive selection. In our current study, we focus on the lipid kinase Vps34, which has been implicated in autophagy and endocytic vesicle trafficking. We show that loss of Vps34 in TECs causes profound defects in the positive selection of the CD4 T cell lineage but not the CD8 T cell lineage. Utilizing TCR sequencing, we show that T cell selection in conditional mutants causes altered repertoire properties including reduced clonal sharing. cTECs from mutant mice display an increased abundance of invariant chain intermediates bound to surface MHC class II molecules, indicating altered antigen processing. Collectively, these studies identify lipid kinase Vps34 as an important contributor to the repertoire of selecting ligands processed and presented by TECs to developing CD4 T cells.
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Affiliation(s)
- J. Luke Postoak
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN
| | - Wenqiang Song
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN
| | - Guan Yang
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN
| | - Xingyi Guo
- Department of Biomedical Informatics, Vanderbilt University School of Medicine, Nashville, TN
| | - Shiyun Xiao
- Department of Genetics, University of Georgia, Athens, GA
| | - Cherie E. Saffold
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN
| | - Jianhua Zhang
- Department of Pathology, University of Alabama at Birmingham, Birmingham, AL
- Birmingham Veterans Affairs Medical Center, Birmingham, AL
| | - Sebastian Joyce
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN
- Department of Veterans Affairs, Tennessee Valley Healthcare System, Nashville, TN
| | | | - Lan Wu
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN
| | - Luc Van Kaer
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN
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5
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Van Kaer L, Postoak JL, Song W, Wu L. Innate and Innate-like Effector Lymphocytes in Health and Disease. J Immunol 2022; 209:199-207. [PMID: 35821102 PMCID: PMC9285656 DOI: 10.4049/jimmunol.2200074] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Accepted: 03/11/2022] [Indexed: 04/20/2023]
Abstract
Lymphocytes can be functionally partitioned into subsets belonging to the innate or adaptive arms of the immune system. Subsets of innate and innate-like lymphocytes may or may not express Ag-specific receptors of the adaptive immune system, yet they are poised to respond with innate-like speed to pathogenic insults but lack the capacity to develop classical immunological memory. These lymphocyte subsets display a number of common properties that permit them to integrate danger and stress signals dispatched by innate sensor cells to facilitate the generation of specialized effector immune responses tailored toward specific pathogens or other insults. In this review, we discuss the functions of distinct subsets of innate and innate-like lymphocytes. A better understanding of the mechanisms by which these cells are activated in different contexts, their interactions with other immune cells, and their role in health and disease may inform the development of new or improved immunotherapies.
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Affiliation(s)
- Luc Van Kaer
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN
| | - J Luke Postoak
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN
| | - Wenqiang Song
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN
| | - Lan Wu
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN
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6
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Yang G, Postoak JL, Song W, Martinez J, Zhang J, Wu L, Van Kaer L. Dendritic cell PIK3C3/VPS34 controls the pathogenicity of CNS autoimmunity independently of LC3-associated phagocytosis. Autophagy 2021; 18:161-170. [PMID: 33960279 DOI: 10.1080/15548627.2021.1922051] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
PIK3C3/VPS34 is a key player in macroautophagy/autophagy and MAP1LC3/LC3-associated phagocytosis (LAP), which play critical roles in dendritic cell (DC) function. In this study, we assessed the contribution of PIK3C3 to DC function during experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis (MS). We found that Pik3c3-deficient DCs exhibit attenuated capacity to reactivate encephalitogenic T cells in the central nervous system, leading to reduced incidence and severity of EAE in DC-specific Pik3c3-deficient mice. Additionally, animals with a DC-specific deficiency in Rb1cc1/Fip200 but not Rubcn were protected against EAE, suggesting that the EAE phenotype of DC-specific Pik3c3-deficient mice is due to defective canonical autophagy rather than LAP. Collectively, our studies have revealed a critical role of PIK3C3 in DC function and the pathogenicity of these cells during EAE, with important implications for the development of immunotherapies for autoimmune diseases such as MS.
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Affiliation(s)
- Guan Yang
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - J Luke Postoak
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Wenqiang Song
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Jennifer Martinez
- Immunity, Inflammation, and Disease Laboratory, National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA
| | - Jianhua Zhang
- Department of Pathology, University of Alabama at Birmingham, Birmingham, AL, USA.,Department of Veterans Affairs, Birmingham Veterans Affairs Medical Center, Birmingham, AL, USA
| | - Lan Wu
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Luc Van Kaer
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN, USA
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7
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Song W, Yang G, Postoak JL, Zhang J, Wu L, Van Kaer L. Adipocyte-specific PIK3C3/VPS34 controls adipogenesis, metabolically-triggered inflammation, insulin resistance, and adaptive thermogenesis in mice. The Journal of Immunology 2021. [DOI: 10.4049/jimmunol.206.supp.13.07] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/10/2023]
Abstract
Abstract
Interactions between cells of the immune and metabolic systems play critical roles in controlling immune responsiveness and metabolic health. When these interactions are dysregulated, metabolic diseases such as obesity or lipodystrophy may develop. We have focused on cellular processes related to autophagy, a cellular self-degradation process, in controlling interactions between the immune and metabolic systems. In this study, we analyzed mice with an adipocyte-selective deficiency in PIK3C3/VPS34, a key early player in autophagy. These animals showed reduced white and brown adipose tissue (WAT and BAT) with enhanced macrophage infiltration, systemic immune activation, and spontaneous insulin-resistance. The phenotype of these animals bears a striking resemblance with the disease manifestations seen in individuals with lipodystrophy. Mechanistically, we found that conditional Pik3c3-deficiency inhibits adipogenesis in both WAT and BAT by downregulating glucose uptake and fatty acid metabolism, and impairs the thermogenic function of BAT by downregulating the expression of key regulators (Prdm16, Ucp1, and Cidea). Upon acute cold exposure, Pik3c3-deficient mice became cold-sensitive under fasting conditions due to insufficient thermogenesis in BAT. In contrast, these animals exhibited blunted beige fat thermogenesis in subcutaneous WAT in response to administration of a b3-adrenergic receptor agonist. Collectively, our data demonstrate that PIK3C3 is a vital regulator of adipose tissue development, metabolically-triggered inflammation, insulin resistance, and adaptive thermogenesis. Hence, we identify PIK3C3 as a potential therapeutic target for metabolic diseases such as type 2 diabetes.
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Affiliation(s)
- Wenqiang Song
- 1Pathology, Microbiology & Immunology Vanderbilt Univ. Med. Ctr
| | - Guan Yang
- 1Pathology, Microbiology & Immunology Vanderbilt Univ. Med. Ctr
| | - J. Luke Postoak
- 1Pathology, Microbiology & Immunology Vanderbilt Univ. Med. Ctr
| | | | - Lan Wu
- 1Pathology, Microbiology & Immunology Vanderbilt Univ. Med. Ctr
| | - Luc Van Kaer
- 1Pathology, Microbiology & Immunology Vanderbilt Univ. Med. Ctr
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8
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Yang G, Postoak JL, Song W, Martinez J, Zhang J, Wu L, Van Kaer L. Dendritic cell PIK3C3/VPS34 controls the pathogenicity of CNS autoimmunity independently of LC3-associated phagocytosis. The Journal of Immunology 2021. [DOI: 10.4049/jimmunol.206.supp.93.04] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/10/2023]
Abstract
Abstract
The PIK3C3/VPS34 subunit of the class III phosphatidylinositol 3-kinase (PtdIns3K) complex is a key player in macroautophagy/autophagy and MAP1LC3/LC3-associated phagocytosis (LAP), both of which play critical roles in mediating dendritic cell (DC) function. In this study, we assessed the contribution of PIK3C3 to DC function in the context of experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis (MS). We found that Pik3c3-deficient DCs exhibited attenuated ability in reactivating encephalitogenic T cells in the central nervous system, leading to reduced incidence and severity of EAE in DC-specific Pik3c3-deficient mice. Additionally, animals with DC-specific deficiency of Rb1cc1 (essential for autophagosome nucleation but not LAP) but not Rubcn (required for LAP but not autophagy) were protected against EAE, suggesting that the EAE phenotype of DC-specific Pik3c3-deficient mice is associated with the lack of canonical autophagy rather than LAP. Collectively, our studies have revealed a critical role of PIK3C3 in DC function and in the pathogenicity of these cells during EAE. Our findings also have important implications for the development of immunotherapies to treat autoimmune diseases such as MS by targeting PIK3C3-containing complexes.
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Affiliation(s)
- Guan Yang
- 1Pathology, Microbiology & Immunology Vanderbilt Univ. Med. Ctr
| | - J. Luke Postoak
- 1Pathology, Microbiology & Immunology Vanderbilt Univ. Med. Ctr
| | - Wenqiang Song
- 1Pathology, Microbiology & Immunology Vanderbilt Univ. Med. Ctr
| | | | | | - Lan Wu
- 1Pathology, Microbiology & Immunology Vanderbilt Univ. Med. Ctr
| | - Luc Van Kaer
- 1Pathology, Microbiology & Immunology Vanderbilt Univ. Med. Ctr
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9
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Yang G, Song W, Postoak JL, Martinez J, Zhang J, Wu L, Van Kaer L. Autophagy-related protein VPS34 controls the homeostasis and function of macrophages. The Journal of Immunology 2020. [DOI: 10.4049/jimmunol.204.supp.152.9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Abstract
Vacuolar protein sorting 34 (VPS34; also known as PIK3C3) plays a role in both canonical and noncanonical autophagy, key processes that control immune cell responsiveness to a variety of stimuli. Our previous studies found that VPS34 is a critical regulator that controls the development, homeostasis, and function of dendritic cells and T cells. In this study, we investigated the role of VPS34 in macrophage biology using myeloid cell-specific Vps34-deficient mice. We found that Vps34-deficient macrophages express increased surface levels of MHC class I and class II molecules. Interestingly, Vps34 ablation in macrophages caused a partial impairment in the homeostatic maintenance of TIM-4+ macrophages and defective uptake of apoptotic cells. In addition, myeloid cell-specific Vps34-deficient animals showed significantly reduced severity of experimental autoimmune encephalomyelitis (EAE), a primarily CD4+ T cell-mediated mouse model of multiple sclerosis. Importantly, peritoneal macrophages from mice deficient in the VPS34-associated protein RUBICON, which is critical for a noncanonical form of autophagy called light chain (LC) 3-associated phagocytosis (LAP), showed normal MHC class I, MHC class II, and TIM-4 expression and Rubicon−/− mice developed signs of EAE similar to wild-type control mice. These results suggested that the canonical autophagy-dependent activities of VPS34 play a critical role in controlling macrophage homeostasis and function. Collectively, our studies establish VPS34 as an important regulator of macrophage functions and macrophage-mediated regulation of EAE. Our findings also have important implications for the development of small-molecule inhibitors of VPS34 for therapeutic purposes.
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Affiliation(s)
- Guan Yang
- 1Pathology, Microbiology & Immunology; Vanderbilt University Medical Center, Nashville, TN
| | - Wenqiang Song
- 1Pathology, Microbiology & Immunology; Vanderbilt University Medical Center, Nashville, TN
| | - J. Luke Postoak
- 1Pathology, Microbiology & Immunology; Vanderbilt University Medical Center, Nashville, TN
| | | | - Jianhua Zhang
- 3Department of Pathology, University of Alabama at Birmingham, Birmingham, AL
- 4Birmingham Veterans Affairs Medical Center, Birmingham, AL
| | - Lan Wu
- 1Pathology, Microbiology & Immunology; Vanderbilt University Medical Center, Nashville, TN
| | - Luc Van Kaer
- 1Pathology, Microbiology & Immunology; Vanderbilt University Medical Center, Nashville, TN
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10
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Yang G, Song W, Postoak JL, Chen J, Martinez J, Zhang J, Wu L, Van Kaer L. Autophagy-related protein PIK3C3/VPS34 controls T cell metabolism and function. Autophagy 2020; 17:1193-1204. [PMID: 32268825 DOI: 10.1080/15548627.2020.1752979] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
The PIK3C3/VPS34 subunit of the class III phosphatidylinositol 3-kinase (PtdIns3K) complex is a key early player in macroautophagy/autophagy. In this study, we assessed the contribution of PIK3C3 to T cell metabolism and function. We found that Pik3c3-deficient T cells exhibited impaired cellular metabolism, and Pik3c3-deficient CD4+ T cells failed to differentiate into T helper 1 cells. These alterations were associated with reduced levels of active mitochondria upon T cell activation. In addition, conditional Pik3c3-deficient animals failed to mount autoreactive T cell responses and were resistant to experimental autoimmune encephalomyelitis (EAE). Interestingly, the deletion of Pik3c3 had little effect on the capacity of animals to clear tumor metastases. Collectively, our studies have revealed a critical role of PIK3C3 in T cell metabolism and the pathogenicity of these cells during EAE. Our findings also have important implications for the development of immunotherapies to treat multiple sclerosis and other inflammatory diseases by targeting PIK3C3.Abbreviations: CNS: central nervous system; DC: dendritic cell; DEG: differentially expressed gene; EAE: experimental autoimmune encephalomyelitis; ECAR: extracellular acidification rate; iNKT: invariant natural killer T; LAP: LC3-associated phagocytosis; LLC: Lewis lung carcinoma; MAP1LC3/LC3: microtubule-associated protein 1 light chain 3; MDSC: myeloid-derived suppressor cell; MOG: myelin oligodendrocyte glycoprotein; NK: natural killer; OCR: oxygen consumption rate; PI: propidium iodide; PIK3C3/VPS34: phosphatidylinositol 3-kinase catalytic subunit type 3; RNA-seq: RNA-sequencing; TCR: T cell receptor; TMRE: tetramethylrhodamine ethyl ester perchlorate.
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Affiliation(s)
- Guan Yang
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Wenqiang Song
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN, USA.,Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - J Luke Postoak
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Jin Chen
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN, USA.,Veterans Affairs Medical Center, Tennessee Valley Healthcare System, Nashville, TN, USA
| | - Jennifer Martinez
- Immunity, Inflammation, and Disease Laboratory, National Institute of Environmental Health Sciences, Research Triangle Park, Durham, NC, USA
| | - Jianhua Zhang
- Department of Pathology, University of Alabama at Birmingham, Birmingham, AL, USA.,Birmingham Veterans Affairs Medical Center, Birmingham, AL, USA
| | - Lan Wu
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Luc Van Kaer
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN, USA
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11
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Van Kaer L, Parekh VV, Postoak JL, Wu L. Role of autophagy in MHC class I-restricted antigen presentation. Mol Immunol 2017; 113:2-5. [PMID: 29126597 DOI: 10.1016/j.molimm.2017.10.021] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Revised: 10/24/2017] [Accepted: 10/25/2017] [Indexed: 12/20/2022]
Abstract
Major histocompatibility complex (MHC) class I molecules present peptide antigens to MHC class I-restricted CD8+ T lymphocytes. The peptides loaded onto MHC class I molecules are typically derived from cytosolic antigens, which includes both self and foreign proteins. In addition to this classical MHC class I antigen presentation pathway, some cell types, especially dendritic cells can present antigens from exogenous sources to MHC class I-restricted CD8+ T cells, in a process called cross-presentation. A variety of cellular processes, including endocytosis, vesicle trafficking, and autophagy, play critical roles in these antigen presentation pathways. In this review article, we discuss the role of autophagy, an intracellular degradation system that delivers cytoplasmic constituents to lysosomes, in MHC class I-restricted antigen presentation. A mechanistic understanding of the role of autophagy-related proteins in MHC class I restricted antigen presentation may guide future efforts in manipulating autophagy to prevent or treat human disease.
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Affiliation(s)
- Luc Van Kaer
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
| | - Vrajesh V Parekh
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - J Luke Postoak
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Lan Wu
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
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