Non-canonical Autophagy Research Articles

Modulation of the immunity and inflammation by autophagy.

Autophagy, a highly conserved cellular self-degradation pathway, has emerged with novel roles in the realms of immunity and inflammation. Genome-wide association studies have unveiled a correlation between genetic variations in autophagy-related genes and heightened susceptibility to autoimmune and inflammatory diseases. Subsequently, substantial progress has been made in unraveling the intricate involvement of autophagy in immunity and inflammation through functional studies. The autophagy pathway plays a crucial role in both innate and adaptive immunity, encompassing various key functions such as pathogen clearance, antigen processing and presentation, cytokine production, and lymphocyte differentiation and survival. Recent research has identified novel approaches in which the autophagy pathway and its associated proteins modulate the immune response, including noncanonical autophagy. This review provides an overview of the latest advancements in understanding the regulation of immunity and inflammation through autophagy. It summarizes the genetic associations between variants in autophagy-related genes and a range of autoimmune and inflammatory diseases, while also examining studies utilizing transgenic animal models to uncover the in vivo functions of autophagy. Furthermore, the review delves into the mechanisms by which autophagy dysregulation contributes to the development of three common autoimmune and inflammatory diseases and highlights the potential for autophagy-targeted therapies.

LC3B is lipidated to large lipid droplets during prolonged starvation for noncanonical autophagy.

Lipid droplets (LDs) store lipids that can be utilized during times of scarcity via autophagic and lysosomal pathways, but how LDs and autophagosomes interact remained unclear. Here, we discovered that the E2 autophagic enzyme, ATG3, localizes to the surface of certain ultra-large LDs in differentiated murine 3T3-L1 adipocytes or Huh7 human liver cells undergoing prolonged starvation. Subsequently, ATG3 lipidates microtubule-associated protein 1 light-chain 3B (LC3B) to these LDs. Invitro, ATG3 could bind alone to purified and artificial LDs to mediate this lipidation reaction. We observed that LC3B-lipidated LDs were consistently in close proximity to collections of LC3B-membranes and were lacking Plin1. This phenotype is distinct from macrolipophagy, but it required autophagy because it disappeared following ATG5 or Beclin1 knockout. Our data suggest that extended starvation triggers a noncanonical autophagy mechanism, similar to LC3B-associated phagocytosis, in which the surface of large LDs serves as an LC3B lipidation platform for autophagic processes.

Heterozygosity for Crohn’s Disease Risk Allele of Atg16L1 Protects from Salmonella Infection

Abstract Autophagy is an evolutionarily conserved pathway for the formation and trafficking of lipid vesicles in response to stress, including inflammation and microbial infection. A missense variant of the essential autophagy gene Atg16L1 (rs2241880, T300A) is carried by a majority of the human population and is linked to Crohn’s Disease (CD). Previous studies found that T300A enhances proteolytic cleavage and degradation of Atg16L1, leading to dysregulated cytokine expression and impaired control of microbial infection in knock-in mice. However, these studies have focused on homozygous animals while the plurality of the human population is heterozygous for the allele. Here we demonstrate that heterozygosity for T300A protects mice from Salmonella infection. We find the variant allele results in altered complex formation independent of cleavage, allowing for enhanced inflammasome activation but impaired conjugation of Atg8 to single membranes (CASM). In vivo, one copy of T300A is sufficient to elevate the production of inflammatory cytokines, which is required for protection from Salmonella infection. Meanwhile, mice deficient in CASM genes are susceptible to Salmonella infection and this pathway is shown to be impaired in homozygous but not heterozygous mice. Finally, we demonstrate that heterozygosity in human macrophages also results in elevated cytokine expression, while maintaining functional non-canonical autophagy. These results clarify the altered autophagy function of the CD risk allele Atg16L1T300A and suggest it can be beneficial to heterozygous carriers, providing a potential explanation for its prevalence in the human population. NIH R01 AI121244 F31 HL149238

Autophagy and LC3-associated phagocytosis: similarities and differences

Previously, autophagy was termed as a mechanism used by the cells with a lack of essential nutrients supporting homeostasis. Over the decade of studies, autophagy proved to be a more complex, ambiguous mechanism. Its activation depends on the nature of stimulus, type of immune cells and the final result. Both canonical and non-canonical autophagy, being similar in molecular events, but showing their own distinctive features, are key processes in protecting the body from penetration of intracellular pathogens, maintaining the required level of nutrients in the cell, and removing damaged organelles and cells. Canonical autophagy probably evolved as a homeostatic response to cellular stress and nutritional deficiencies, whereas non-canonical autophagy emerged as a response to suppression of inflammation. Non-canonical autophagy, hereinafter referred to as LC3-associated phagocytosis (LAP), combines the molecular mechanism of phagocytosis with an autophagy mechanism characterized by ingestion of exogenous pathogens, formation of phagosomes (laposomes) and enhanced fusion with lysosomes, followed by degradation of their contents.Significant differences were found between the processes of LAP- and canonical autophagy, which are similar in its mechanism of action. The presence of PI3K complexes in both processes, utilization and intracellular degradation of the “cargo” which is not required for the cells and organism proceeding in the lysosomes, and involvement of almost the same proteins provide similarity of their mechanisms. However, there are differences in the initiation of the processes, e.g., different types of PI3K complexes (in autophagy, PI3K III class 1 and 2 types; in LAP PI3K III, class 3 type), usage of reactive oxygen species in LAP, different types of regulatory proteins involved (ULK1, FIP200, ATG13 , Ambra1, WIPI2, ATG14 in autophagy; and Rubicon and NOX2 in LC3-associated phagocytosis), different number of layers in the membrane structure in which lysis occurs (double-membrane autophagolysosome and single-layer membrane in laposomes) clearly depict the variety of canonical and non-canonical autophagy. The two pathways are directed for different types of biological objects, i.e., intracellular pathogens, dysfunctional proteins and organelles in autophagy, and extracellular pathogens, apoptotic bodies, bacteria, utilized in LAP, thus making these mechanisms completely different in their significance.Collectively, the new data indicate that autophagy performed via both canonical and non-canonical pathways, has evolved into a host defense mechanism capable of resisting immunological and pathogenic stress and mediating immunological tolerance to both intra- and extracellular threats. The present review discusses fundamental molecular differences between these mechanisms, as well as their role in immunity, based on the latest literature data.

Construction of endothelial cell-related and autophagy-related prognostic models for hepatocellular carcinoma based on single-cell data.

We aimed to develop an autophagy-related prognostic model with single-cell RNA sequencing (ScRNA-Seq) data for hepatocellular carcinoma (HCC) patients. ScRNA-Seq datasets of HCC patients were analyzed by Seurat. The expression of genes involved in canonical and noncanonical autophagy pathways in scRNA-seq data was also compared. Cox regression was applied to construct an AutRG risk prediction model. Subsequently, we examined the characteristics of AutRG high-risk and low-risk group patients. Six major cell types (hepatocytes, myeloid cells, T/NK cells, B cells, fibroblast cells, and endothelial cells) were identified in the scRNA-Seq dataset. The results showed that most of the canonical and noncanonical autophagy genes were highly expressed in hepatocytes, with the exception of MAP 1LC3B, SQSTM1, MAP 1LC3A, CYBB, and ATG3. Six AutRG risk prediction models originating from different cell types were constructed and compared. The AutRG prognostic signature (GAPDH, HSP90AA1, and TUBA1C) in endothelial cells had the best overall performance for predicting the overall survival of HCC patients, with 1-year, 3-year, and 5-year AUCs equal to 0.758, 0.68, and 0.651 in the training cohort and 0.760, 0.796, and 0.840 in the validation cohort, respectively. The different tumor mutation burden, immune infiltration, and gene set enrichment characteristics of the AutRG high-risk and low-risk group patients were identified. We constructed an endothelial cell-related and autophagy-related prognostic model of HCC patients using the ScRNA-Seq dataset for the first time. This model demonstrated the good calibration ability of HCC patients and provided a new understanding of the evaluation of prognosis.

ATG7 and ATG14 restrict cytosolic and phagosomal Mycobacterium tuberculosis replication in human macrophages

Autophagy is a cellular innate-immune defence mechanism against intracellular microorganisms, including Mycobacterium tuberculosis (Mtb). How canonical and non-canonical autophagy function to control Mtb infection in phagosomes and the cytosol remains unresolved. Macrophages are the main host cell in humans for Mtb. Here we studied the contributions of canonical and non-canonical autophagy in the genetically tractable human induced pluripotent stem cell-derived macrophages (iPSDM), using a set of Mtb mutants generated in the same genetic background of the common lab strain H37Rv. We monitored replication of Mtb mutants that are either unable to trigger canonical autophagy (Mtb ΔesxBA) or reportedly unable to block non-canonical autophagy (Mtb ΔcpsA) in iPSDM lacking either ATG7 or ATG14 using single-cell high-content imaging. We report that deletion of ATG7 by CRISPR–Cas9 in iPSDM resulted in increased replication of wild-type Mtb but not of Mtb ΔesxBA or Mtb ΔcpsA. We show that deletion of ATG14 resulted in increased replication of both Mtb wild type and the mutant Mtb ΔesxBA. Using Mtb reporters and quantitative imaging, we identified a role for ATG14 in regulating fusion of phagosomes containing Mtb with lysosomes, thereby enabling intracellular bacteria restriction. We conclude that ATG7 and ATG14 are both required for restricting Mtb replication in human macrophages.

AUTOPHAGY IN THE EYE: FROM PHYSIOLOGY TO PATHOPHYSOLOGY.

Autophagy is a catabolic self-degradative pathway that promotes the degradation and recycling of intracellular material through the lysosomal compartment. Although first believed to function in conditions of nutritional stress, autophagy is emerging as a critical cellular pathway, involved in a variety of physiological and pathophysiological processes. Autophagy dysregulation is associated with an increasing number of diseases, including ocular diseases. On one hand, mutations in autophagy-related genes have been linked to cataracts, glaucoma, and corneal dystrophy; on the other hand, alterations in autophagy and lysosomal pathways are a common finding in essentially all diseases of the eye. Moreover, LC3-associated phagocytosis, a form of non-canonical autophagy, is critical in promoting visual cycle function. This review collects the latest understanding of autophagy in the context of the eye. We will review and discuss the respective roles of autophagy in the physiology and/or pathophysiology of each of the ocular tissues, its diurnal/circadian variation, as well as its involvement in diseases of the eye.

Non-canonical autophagy in aging and age-related diseases.

Autophagy, one of the arms of proteostasis, influences aging and age-related diseases. Recently, the discovery of additional roles of autophagy-related proteins in non-canonical degradation and secretion has revealed alternative fates of autophagic cargo. Some of these non-canonical pathways have been linked to neurodegenerative diseases and improving the understanding of this link is crucial for their potential targetability in aging and age-related diseases. This review discusses recent investigations of the involvement of non-canonical autophagy players and pathways in age-related diseases that are now beginning to be discovered. Unraveling these pathways and their relation to classical autophagy could unearth a fascinating new layer of proteostasis regulation during normal aging and in longevity.

The Autophagy Marker LC3 Is Processed during the Sperm Capacitation and the Acrosome Reaction and Translocates to the Acrosome Where It Colocalizes with the Acrosomal Membranes in Horse Spermatozoa

Despite its importance in somatic cells and during spermatogenesis, little is known about the role that autophagy may play in ejaculated spermatozoa. Our aim was to investigate whether the molecular components of autophagy, such as microtubule-associated protein 1 light chain 3 (LC3), are activated in stallion spermatozoa during the capacitation and acrosome reaction and if this activation could modulate these biological processes. To analyze the autophagy turnover, LC3I and LC3II proteins were assessed by western blotting, and the ratio between both proteins (LC3II/LC3I) was calculated. In somatic cells, this ratio indicates that autophagy has been activated and similar LC3 processing has been described in mammalian spermatozoa. The subcellular localization of autophagy-related proteins was assessed by immunofluorescence with specific antibodies that recognized Atg16, Beclin-1, and LC3. The colocalization of acrosomal membranes (PNA) and LC3 was studied by confocal microcopy, and the acrosome reacted cells were quantified by flow cytometry. The incubation of stallion sperm in capacitating conditions (BWW; 3 h) significantly increased LC3 processing. This increment was three to four times higher after the induction of the acrosome reaction in these cells. LC3 was mainly expressed in the head in mature ejaculated sperm showing a clear redistribution from the post-acrosomal region to the acrosome upon the incubation of sperm in capacitating conditions (BWW, 3 h). After the induction of the acrosome reaction, LC3 colocalized with the acrosome or the apical plasmalemma membranes in the head of the stallion spermatozoa. The inhibition or activation of autophagy-related pathways in the presence of autophagy activators (STF-62247) or inhibitors (E-64d, chloroquine) significantly increased LC3 processing and increased the percent of acrosome reacted cells, whereas 3-methyladenine almost completely inhibited LC3 processing and the acrosome reaction. In conclusion, we found that sperm capacitation and acrosome reaction could be regulated by autophagy components in sperm cells ex vivo by processes that might be independent of the intraluminal pH of the acrosome and dependent of LC3 lipidation. It can be speculated that, in stallion sperm, a form of noncanonical autophagy utilizes some components of autophagy machinery to facilitate the acrosome reaction.

Abstract 2020: Mechanistic insights into BECN2:Syntaxin6 complex-mediated vesicle fusion during non-canonical autophagy

Abstract 2020: Mechanistic insights into BECN2:Syntaxin6 complex-mediated vesicle fusion during non-canonical autophagy

Analysis of LC3-Associated Phagocytosis and Antigen Presentation in Macrophages and B Cells.

Canonical autophagy and the non-canonical autophagy pathway LC3-associated phagocytosis (LAP) play crucial roles in the immune system by processing antigens for major histocompatibility complex (MHC) class II restricted presentation to CD4+ T cells. Recent studies offer insight into the relationship between LAP, autophagy, and antigen processing in macrophages and dendritic cells; however their involvement during antigen processing in B cells is less well understood.In this chapter, we describe how to monitor, manipulate, and understand the role of LAP and classical autophagy during MHC-restricted antigen presentation by human monocyte-derived macrophages as well as in B cell lymphoblastoid cell lines (LCLs). It includes an explanation on how to generate LCLs and monocyte-derived macrophages from primary human cells. Then we describe two different approaches to manipulate the autophagy pathways: silencing of the atg4b gene using CRISPR/Cas9 technology and a lentivirus delivery system for specific ATG4B overexpression. We also propose a method for triggering LAP and measuring different ATG proteins using Western blot and immunofluorescence. Finally, we show an approach to investigate MHC class II antigen presentation by an in vitro co-culture assay that uses the measurement of secreted cytokines, released by activated CD4+ T cells, as readout.

Canonical and Noncanonical ER Stress-Mediated Autophagy Is a Bite the Bullet in View of Cancer Therapy

Cancer cells adapt multiple mechanisms to counter intense stress on their way to growth. Tumor microenvironment stress leads to canonical and noncanonical endoplasmic stress (ER) responses, which mediate autophagy and are engaged during proteotoxic challenges to clear unfolded or misfolded proteins and damaged organelles to mitigate stress. In these conditions, autophagy functions as a cytoprotective mechanism in which malignant tumor cells reuse degraded materials to generate energy under adverse growing conditions. However, cellular protection by autophagy is thought to be complicated, contentious, and context-dependent; the stress response to autophagy is suggested to support tumorigenesis and drug resistance, which must be adequately addressed. This review describes significant findings that suggest accelerated autophagy in cancer, a novel obstacle for anticancer therapy, and discusses the UPR components that have been suggested to be untreatable. Thus, addressing the UPR or noncanonical ER stress components is the most effective approach to suppressing cytoprotective autophagy for better and more effective cancer treatment.

Many roads lead to CASM: Diverse stimuli of noncanonical autophagy share a unifying molecular mechanism.

Autophagy is a fundamental catabolic process coordinated by a network of autophagy-related (ATG) proteins. These ATG proteins also perform an important parallel role in "noncanonical" autophagy, a lysosome-associated signaling pathway with key functions in immunity, inflammation, cancer, and neurodegeneration. While the noncanonical autophagy pathway shares the common ATG machinery, it bears key mechanistic and functional distinctions, and is characterized by conjugation of ATG8 to single membranes (CASM). Here, we review the diverse, and still expanding, collection of stimuli and processes now known to harness the noncanonical autophagy pathway, including engulfment processes, drug treatments, TRPML1 and STING signaling, viral infection, and other pathogenic factors. We discuss the multiple associated routes to CASM and assess their shared and distinctive molecular features. By integrating these findings, we propose an updated and unifying mechanism for noncanonical autophagy, centered on ATG16L1 and V-ATPase.

Beyond autophagy: LC3-associated phagocytosis and endocytosis.

Noncanonical functions of the autophagy machinery in pathways including LC3-associated phagocytosis and LC3-associated endocytosis have garnered increasing interest in both normal physiology and pathobiology. New discoveries over the past decade of noncanonical uses of the autophagy machinery in these distinct molecular mechanisms have led to robust investigation into the roles of single-membrane LC3 lipidation. Noncanonical autophagy pathways have now been implicated in the regulation of multiple processes ranging from debris clearance, cellular signaling, and immune regulation and inflammation. Accumulating evidence is demonstrating roles in a variety of disease states including host-pathogen responses, autoimmunity, cancer, and neurological and neurodegenerative pathologies. Here, we broadly summarize the differences in the mechanistic regulation between autophagy and LAP and LANDO and highlight some of the key roles of LAP and LANDO in innate immune function, inflammation, and disease pathology.

Insights on attenuating autophagy cellular and molecular pathways versus methotrexate-induced toxicity via liposomal turmeric therapy

BackgroundMethotrexate (MX), a competitive inhibitor of dihydrofolate reductase, can inhibit DNA and RNA production and is a powerful anticancer agent widely utilized in clinical practice for treating nonneoplastic maladies, as psoriasis and rheumatoid arthritis; meanwhile, its probable prescription dose and interval of administration are strictly limited due to dose-related organ damage. Former studies verified that kidney, brain, liver, and lung harms are prospective obstacles of methotrexate administration. To understand the machinery of methotrexate-prompt toxicity, various mechanisms were investigated. The former is an autophagy defense mechanism; autophagy is a self-digesting mechanism responsible for the removal of damaged organelles and malformed proteins by lysosome. The contemporary article hypothesized that turmeric or its liposomal analog could defeat autophagy of MX-induced acute toxicity. Methotrexate, in a dose of 1.5 mg/kg, was administered intravenously followed by turmeric and liposomal turmeric treatment in a dose of 5 mg/kg for 30 days in rats. ResultsIncrement in autophagy (AUTP) consent by MX administration was attenuated by concurrent treatment via turmeric and liposomal turmeric that was reliable on the alteration in apoptotic markers. The assembly of FOXO-3 in serum post methotrexate administration was suppressed by concurrent treatment via liposomal turmeric. Apoptosis/autophagic marker investigation was evaluated through the gene expression of Bax (BCL2-associated X protein)/Bcl2 (B-cell lymphoma 2)/P53 (tumor protein P53)/SiRT-1 (sirtuin silent mating-type information regulation 2 homolog 1) and FOXO-3 (forkhead box transcription factor-3)/ERDJ-4 (endoplasmic reticulum localized DnaJ homologs)/BNP (brain natriuretic peptide B) signaling. The cell death of all cells was categorized to achieve autophagy. Interestingly, Bax/Bcl2/P53/SiRT-1 signaling pathways were downregulated, contributing to inhibiting the initiation of autophagy. Meanwhile, FOXO-3/BNP/ERDJ-4 reduction-implicated noncanonical autophagy pathways were involved in methotrexate-induced autophagy, whereas this change was suppressed when turmeric was administered in liposomal form. ConclusionThese outcomes recommended that liposomal turmeric prevents MX-induced acute toxicity through its autophagy, antioxidant, and antiapoptotic properties.

Microglial debris is cleared by astrocytes via C4b-facilitated phagocytosis and degraded via RUBICON-dependent noncanonical autophagy in mice

Microglia are important immune cells in the central nervous system (CNS) that undergo turnover throughout the lifespan. If microglial debris is not removed in a timely manner, accumulated debris may influence CNS function. Clearance of microglial debris is crucial for CNS homeostasis. However, underlying mechanisms remain obscure. We here investigate how dead microglia are removed. We find that although microglia can phagocytose microglial debris in vitro, the territory-dependent competition hinders the microglia-to-microglial debris engulfment in vivo. In contrast, microglial debris is mainly phagocytosed by astrocytes in the brain, facilitated by C4b opsonization. The engulfed microglial fragments are then degraded in astrocytes via RUBICON-dependent LC3-associated phagocytosis (LAP), a form of noncanonical autophagy. Interference with C4b-mediated engulfment and subsequent LAP disrupt the removal and degradation of microglial debris, respectively. Together, we elucidate the cellular and molecular mechanisms of microglial debris removal in mice, extending the knowledge on the maintenance of CNS homeostasis.

Intercellular transfer of activated STING triggered by RAB22A-mediated non-canonical autophagy promotes antitumor immunity

STING, an endoplasmic reticulum (ER) transmembrane protein, mediates innate immune activation upon cGAMP stimulation and is degraded through autophagy. Here, we report that activated STING could be transferred between cells to promote antitumor immunity, a process triggered by RAB22A-mediated non-canonical autophagy. Mechanistically, RAB22A engages PI4K2A to generate PI4P that recruits the Atg12–Atg5–Atg16L1 complex, inducing the formation of ER-derived RAB22A-mediated non-canonical autophagosome, in which STING activated by agonists or chemoradiotherapy is packaged. This RAB22A-induced autophagosome fuses with RAB22A-positive early endosome, generating a new organelle that we name Rafeesome (RAB22A-mediated non-canonical autophagosome fused with early endosome). Meanwhile, RAB22A inactivates RAB7 to suppress the fusion of Rafeesome with lysosome, thereby enabling the secretion of the inner vesicle of the autophagosome bearing activated STING as a new type of extracellular vesicle that we define as R-EV (RAB22A-induced extracellular vesicle). Activated STING-containing R-EVs induce IFNβ release from recipient cells to the tumor microenvironment, promoting antitumor immunity. Consistently, RAB22A enhances the antitumor effect of the STING agonist diABZI in mice, and a high RAB22A level predicts good survival in nasopharyngeal cancer patients treated with chemoradiotherapy. Our findings reveal that Rafeesome regulates the intercellular transfer of activated STING to trigger and spread antitumor immunity, and that the inner vesicle of non-canonical autophagosome originated from ER is secreted as R-EV, providing a new perspective for understanding the intercellular communication of organelle membrane proteins.

Interactions of Autophagy and the Immune System in Health and Diseases.

Autophagy is a highly conserved process that utilizes lysosomes to selectively degrade a variety of intracellular cargo, thus providing quality control over cellular components and maintaining cellular regulatory functions. Autophagy is triggered by multiple stimuli ranging from nutrient starvation to microbial infection. Autophagy extensively shapes and modulates the inflammatory response, the concerted action of immune cells, and secreted mediators aimed to eradicate a microbial infection or to heal sterile tissue damage. Here, we first review how autophagy affects innate immune signaling, cell-autonomous immune defense, and adaptive immunity. Then, we discuss the role of non-canonical autophagy in microbial infections and inflammation. Finally, we review how crosstalk between autophagy and inflammation influences infectious, metabolic, and autoimmune disorders.

V. cholerae MakA is a cholesterol-binding pore-forming toxin that induces non-canonical autophagy.

Pore-forming toxins (PFTs) are important virulence factors produced by many pathogenic bacteria. Here, we show that the Vibrio cholerae toxin MakA is a novel cholesterol-binding PFT that induces non-canonical autophagy in a pH-dependent manner. MakA specifically binds to cholesterol on the membrane at pH < 7. Cholesterol-binding leads to oligomerization of MakA on the membrane and pore formation at pH 5.5. Unlike other cholesterol-dependent cytolysins (CDCs) which bind cholesterol through a conserved cholesterol-binding motif (Thr-Leu pair), MakA contains an Ile-Ile pair that is essential for MakA-cholesterol interaction. Following internalization, endosomal acidification triggers MakA pore-assembly followed by ESCRT-mediated membrane repair and V-ATPase-dependent unconventional LC3 lipidation on the damaged endolysosomal membranes. These findings characterize a new cholesterol-binding toxin that forms pores in a pH-dependent manner and reveals the molecular mechanism of host autophagy manipulation.

Transcriptomic analysis of pathways associated with ITGAV/alpha(v) integrin-dependent autophagy in human B cells

ABSTRACT Macroautophagy/autophagy proteins have been linked with the development of immune-mediated diseases including lupus, but the mechanisms for this are unclear due to the complex roles of these proteins in multiple immune cell types. We have previously shown that a form of noncanonical autophagy induced by ITGAV/alpha(v) integrins regulates B cell activation by viral and self-antigens, in mice. Here, we investigate the involvement of this pathway in B cells from human tissues. Our data reveal that autophagy is specifically induced in the germinal center and memory B cell subpopulations of human tonsils and spleens. Transcriptomic analysis show that the induction of autophagy is related to unique aspects of activated B cells such as mitochondrial metabolism. To understand the function of ITGAV/alpha(v) integrin-dependent autophagy in human B cells, we used CRISPR-mediated knockdown of autophagy genes. Integrating data from primary B cells and knockout cells, we found that ITGAV/alpha(v)-dependent autophagy limits activation of specific pathways related to B cell responses, while promoting others. These data provide new mechanistic links for autophagy and B-cell-mediated immune dysregulation in diseases such as lupus.