The innate immune response is the first line of defense for the host against viral infections. Targeted degradation of pathogenic microorganisms through autophagy, in conjunction with pattern recognition receptors synergistically inducing the production of interferon (IFN), constitutes an important pathway for the body to resist viral infections. Rubicon, a Run domain Beclin 1-interacting and cysteine-rich domain protein, has an inhibitory effect on autophagy and IFN production. On the one hand, Rubicon, as a component of the phosphoinositide 3-kinase (PI3K) complex, interacts with different domains of vacuolar protein sorting 34 (Vps34), ultraviolet radiation resistance associated gene (UVRAG), guanosine triphosphate (GTP) kinase, and RAS oncogene family member 7 (Rab7) to mediate the inhibition of autophagy maturation; on the other hand, Rubicon inhibits the ubiquitination of nuclear factor κB essential modulator (NEMO) and the dimerization of interferon regulatory factor 3 (IRF3), thereby blocking the signal transduction related to IFN production. Research has revealed that various viruses, such as Kaposi's sarcoma-associated herpesvirus (KSHV), hepatitis B virus (HBV), Sendai virus (SeV), and hepatitis C virus (HCV), achieve innate immune evasion by regulating the expression or function of Rubicon. Rubicon is expected to be a new target for antiviral therapy.
Humans ; Autophagy/immunology* ; Immunity, Innate ; Interferons/immunology* ; Immune Evasion ; Animals ; Virus Diseases/virology* ; Signal Transduction ; Viruses/immunology* ; Intracellular Signaling Peptides and Proteins/immunology* ; Autophagy-Related Proteins

Autophagy is a fundamental biological metabolic process involved in immune defense, material metabolism, and homeostasis and closely linked to immune regulation. Systemic lupus erythematosus (SLE) is a widespread connective tissue disorder primarily resulting from immune system imbalance. Due to the immune system's failure to recognize its own substances, it generates autoantibodies that can affect various tissues and organs, leading to diverse clinical manifestations. The pathogenesis and treatment of SLE are currently under extensive investigation. In normal metabolic processes, autophagy engages in both innate and adaptive immunity, regulates the immune response, and is crucial for maintaining normal immune function and the body's internal homeostasis. Research has indicated that SLE patients exhibit immune dysfunction and altered autophagy levels. Modulating autophagy expression can influence immune system functionality and alleviate SLE symptoms. Additionally, autophagy aids in the innate immune response and adaptive immunity by clearing metabolites and regulating the life cycle of immune cells. Studies suggest that drugs targeting autophagy can positively influence the progression of SLE. This article reviews advancements in research regarding the impact of autophagy on the pathogenesis of SLE through the regulation of immune system functions.
Lupus Erythematosus, Systemic/pathology* ; Autophagy/immunology* ; Humans ; Animals ; Immunity, Innate ; Adaptive Immunity ; Disease Progression ; Immune System/immunology*

OBJECTIVE: To analyze the effects of mangiferin combined with bortezomib on the proliferation, invasion, apoptosis and autophagy of human Burkitt lymphoma Raji cells, as well as the expression of CXC chemokine receptors (CXCRs) family, and explore the molecular mechanism between them to provide scientific basis for basic research and clinical work of Burkitt lymphoma. METHODS: Raji cells were intervened with different concentrations of mangiferin and bortezomib alone or in combination, then cell proliferation was detected by CCK-8 assay, cell invasion ability was detected by Transwell chamber method, cell apoptosis was detected by Annexin V/PI double-staining flow cytometry, apoptosis, autophagy and Akt/mTOR pathway protein expression were detected by Western blot, and the expression changes of CXCR family was detected by real-time quantitative PCR (RT-qPCR). RESULTS: Different concentrations of mangiferin intervened Raji cells for different time could inhibit cell viability in a concentration- and time-dependent manner (r =-0.682, r =-0.836). When Raji cells were intervened by combination of mangiferin and bortezomib, compared with single drug group, the proliferation and invasion abilities were significantly decreased, while the apoptosis level was significantly increased (P <0.01). Mangiferin combined with bortezomib could significantly up-regulate the expression of pro-apoptotic protein Bax and down-regulate the expression of anti-apoptotic protein Bcl-2 after intervention in Raji cells. Caspase-3 was also hydrolyzed and activated, and then induced the apoptosis of Raji cells. Mangiferin combined with bortezomib could up-regulate the expression of LC3Ⅱ protein in Raji cells, and the ratio of LC3Ⅱ/LC3Ⅰ in cells was significantly up-regulated compared with single drug or control group (P <0.01). Mangiferin combined with bortezomib could significantly inhibit the phosphorylation levels of Akt and mTOR, inhibit the proliferation and invasion of Raji cells by inhibiting Akt/mTOR pathway, and induce cell autophagy and apoptosis. Mangiferin and bortezomib could down-regulate the expressions of CXCR4 and CXCR7 mRNA after single-agent intervention in Raji cells, and the down-regulations of CXCR4 and CXCR7 mRNA expression were more significant when the two drugs were combined (P <0.01). Mangiferin alone or combined with bortezomib had no significant effect on CXCR5 mRNA expression in Raji cells (P >0.05), while the combination of the two drugs could down-regulate the expression of CXCR3 (P <0.05). CONCLUSION Mangiferin combined with bortezomib can synergistically inhibit the proliferation and invasion of Raji cells, and induce autophagy and apoptosis. The mechanism may be related to the inhibition of Akt/mTOR signaling pathway, down-regulation of anti-apoptotic protein Bcl-2 and up-regulation of pro-apoptotic protein Bax, and the inhibition of the expression of CXCR family.
Humans ; Antineoplastic Agents/therapeutic use* ; Apoptosis/drug effects* ; Apoptosis Regulatory Proteins/immunology* ; Autophagy/immunology* ; bcl-2-Associated X Protein/immunology* ; Bortezomib/therapeutic use* ; Burkitt Lymphoma/immunology* ; Cell Line, Tumor ; Cell Proliferation/drug effects* ; Drug Therapy, Combination ; Proto-Oncogene Proteins c-akt ; Proto-Oncogene Proteins c-bcl-2 ; Receptors, CXCR/immunology* ; RNA, Messenger ; TOR Serine-Threonine Kinases ; Xanthones/therapeutic use*

BackgroundImbalance of interferon-gamma (IFN-γ), interleukin (IL)-4, and IL-17 producing by T cells is confirmed to contribute to the pathogenesis of systemic lupus erythematosus (SLE). Autophagy is now emerging as a core player in the development and the function of the immune system. Therefore, we investigated the autophagic behavior in IFN-γ-, IL-4-, and IL-17-producing T cells from patients with SLE.

MethodsThirty patients with SLE and 25 healthy controls matched for gender and age were recruited between September 2016 and May 2017. The autophagic levels in IFN-γ T cells, IL-4 T cells, and IL-17 T cells from patients with newly diagnosed SLE and healthy controls were measured using flow cytometry. The plasma levels of IFN-γ were determined by enzyme-linked immunosorbent assay in SLE patients and healthy controls. Unpaired t-tests and the nonparametric Mann-Whitney U-test were used to compare data from patients with SLE and controls. Spearman's rank correlation coefficient was applied for calculation of the correlation between parallel variables in single samples.

ResultsOur results showed increased percentage of autophagy in IFN-γ T cells from patients with SLE and healthy controls ([8.07 ± 2.72]% vs. [3.76 ± 1.67]%, t = 5.184, P < 0.001), but not in IL-4 T cells or IL-17 T cells (P > 0.05) as compared to healthy donors. Moreover, the plasma levels of IFN-γ in SLE patients were significantly higher than those in healthy controls ([68.9 ± 29.1] pg/ml vs. [24.7 ± 17.6] pg/ml, t = 5.430, P < 0.001). Moreover, in SLE patients, the percentage of autophagy in IFN-γ T cells was positively correlated with the plasma levels of IFN-γ (r = 0.344, P = 0.046), as well as the disease activity of patients with SLE (r = 0.379, P = 0.039).

ConclusionThe results indicate that autophagy in IFN-γ T cells from SLE patients is activated, which might contribute to the persistence of T cells producing IFN-γ, such as Th1 cells, and consequently result in the high plasma levels of IFN-γ, and then enhance the disease activity of SLE.

Adult ; Autophagy ; China ; Female ; Humans ; Interferon-gamma ; metabolism ; Interleukin-17 ; metabolism ; Interleukin-4 ; metabolism ; Lupus Erythematosus, Systemic ; immunology ; Male ; Middle Aged ; Th1 Cells ; physiology

OBJECTIVEThe current study aims to investigate the effect of Hemagglutinating virus of Japan envelope (HVJ-E) on induction of apoptosis and autophagy in human prostate cancer PC3 cells, and the underlying mechanisms.

METHODSPC3 cells were treated with HVJ-E at various multiplicity of infection (MOI), and the generated reactive oxygen species (ROS), cell viability, apoptosis, and autophagy were detected, respectively. Next, the role of ROS played in the regulation of HVJ-E-induced apoptosis and autuphagy in PC3 cells were analysed. In the end, the relationship between HVJ-E-induced apoptosis and autuophagy was investigated by using rapamycin and chloroquine.

RESULTSFlow cytometry assay revealed that HVJ-E treatment induced dose-dependent apoptosis and that the JNK and p38 MAPK signaling pathways were involved in HVJ-E-induced apoptosis in PC3 cells. In addition, HVJ-E was able to induce autophagy in PC3 cells via the class III PI3K/beclin-1 pathway. The data also implyed that HVJ-E-triggered autophagy and apoptosis were ROS dependent. When ROS was blocked with N-acetylcysteine (NAC), HVJ-E-induced LC3-II conversion and apoptosis were reversed. Interestingly, HVJ-E-induced apoptosis was significantly increased by an inducer of autophagy, rapamycin pretreatment, both in vitro and in vivo.

CONCLUSIONHVJ-E exerts anticancer effects via autophagic cell death in prostate cancer cells.

Apoptosis ; physiology ; Autophagy ; physiology ; Cell Line, Tumor ; Cell Survival ; Humans ; Male ; Oncolytic Virotherapy ; Prostatic Neoplasms ; metabolism ; Reactive Oxygen Species ; metabolism ; Sendai virus ; immunology ; physiology ; Virus Inactivation

BACKGROUND/AIMS: Role of autophagy in neutrophil function and the association of autophagy and autophagy related (ATG) gene polymorphisms with asthma susceptibility were suggested. In this study, we investigated the genetic association of ATG5 and ATG7 polymorphisms with asthma risk, severity and neutrophilic airway inflammation. METHODS: We recruited 408 asthma patients and 201 healthy controls. Sputum neutrophil counts were determined by H&E staining. Serum interleukin 8 (IL-8) levels were measured by enzyme-linked immunosorbent assay (ELISA). Genetic polymorphisms of ATG5 (-769T>C, -335G>A, and 8830C>T) and ATG7 (-100A>G and 25108G>C) were genotyped. The functional activities of ATG5 -769T>C and -335G>A variants were investigated by luciferase reporter assays. RESULTS: No associations of ATG5 and ATG7 polymorphisms with asthma susceptibility and severity were found. ATG5 -769T>C and -335G>A were in complete linkage disequilibrium. In the asthma group, GA/AA genotypes at ATG5 -335G>A were associated with higher neutrophil counts in sputum (p < 0.05); CC/TT genotype at ATG5 8830C>T associated with lower FEV1% predicted value (p < 0.05). DNA fragments containing ATG5 -769T and -335G alleles had higher promoter activities compared to those with -769C and -335A in both human airway epithelial cells (A549, p < 0.01) and human mast cell (HMC-1, p < 0.001). GG and CC genotype at ATG7 -100A>G and 25108G>C were significantly associated with high serum levels of IL-8 (p < 0.05 for both variants). CONCLUSIONS: Genetic polymorphisms of ATG5 and ATG7 could contribute to neutrophilic airway inflammation in the pathogenesis of adult asthma.
Adolescent ; Adult ; Asthma/blood/*genetics/immunology/pathology ; Autophagy/*genetics ; Autophagy-Related Protein 5/*genetics ; Autophagy-Related Protein 7/*genetics ; Case-Control Studies ; Cell Line ; Female ; Gene Frequency ; Genes, Reporter ; Genetic Predisposition to Disease ; Haplotypes ; Heterozygote ; Homozygote ; Humans ; Interleukin-8/blood ; Male ; Middle Aged ; Neutrophil Infiltration/*genetics ; Neutrophils/immunology/metabolism/*pathology ; Phenotype ; *Polymorphism, Single Nucleotide ; Promoter Regions, Genetic ; Risk Factors ; Severity of Illness Index ; Transfection ; Young Adult

Nucleotide-binding and oligomerization domain (NOD)-like receptors (NLRs) are pattern-recognition receptors similar to toll-like receptors (TLRs). While TLRs are transmembrane receptors, NLRs are cytoplasmic receptors that play a crucial role in the innate immune response by recognizing pathogen-associated molecular patterns (PAMPs) and damage-associated molecular patterns (DAMPs). Based on their N-terminal domain, NLRs are divided into four subfamilies: NLRA, NLRB, NLRC, and NLRP. NLRs can also be divided into four broad functional categories: inflammasome assembly, signaling transduction, transcription activation, and autophagy. In addition to recognizing PAMPs and DAMPs, NLRs act as a key regulator of apoptosis and early development. Therefore, there are significant associations between NLRs and various diseases related to infection and immunity. NLR studies have recently begun to unveil the roles of NLRs in diseases such as gout, cryopyrin-associated periodic fever syndromes, and Crohn's disease. As these new associations between NRLs and diseases may improve our understanding of disease pathogenesis and lead to new approaches for the prevention and treatment of such diseases, NLRs are becoming increasingly relevant to clinicians. In this review, we provide a concise overview of NLRs and their role in infection, immunity, and disease, particularly from clinical perspectives.
Autophagy/immunology ; Carrier Proteins ; Humans ; *Immunity, Innate ; Inflammasomes ; Nod Signaling Adaptor Proteins/immunology/*metabolism ; Pathogen-Associated Molecular Pattern Molecules ; Receptors, Cytoplasmic and Nuclear/immunology/*metabolism ; Receptors, Pattern Recognition/*immunology ; *Signal Transduction ; Toll-Like Receptors/metabolism

Autophagy plays important roles in modulating viral replication and antiviral immune response. Coronavirus infection is associated with the autophagic process, however, little is known about the mechanisms of autophagy induction and its contribution to coronavirus regulation of host innate responses. Here, we show that the membrane-associated papain-like protease PLP2 (PLP2-TM) of coronaviruses acts as a novel autophagy-inducing protein. Intriguingly, PLP2-TM induces incomplete autophagy process by increasing the accumulation of autophagosomes but blocking the fusion of autophagosomes with lysosomes. Furthermore, PLP2-TM interacts with the key autophagy regulators, LC3 and Beclin1, and promotes Beclin1 interaction with STING, the key regulator for antiviral IFN signaling. Finally, knockdown of Beclin1 partially reverses PLP2-TM's inhibitory effect on innate immunity which resulting in decreased coronavirus replication. These results suggested that coronavirus papain-like protease induces incomplete autophagy by interacting with Beclin1, which in turn modulates coronavirus replication and antiviral innate immunity.
Apoptosis Regulatory Proteins ; antagonists & inhibitors ; genetics ; immunology ; Autophagy ; Beclin-1 ; Coronavirus NL63, Human ; genetics ; immunology ; Gene Expression Regulation ; HEK293 Cells ; HeLa Cells ; Host-Pathogen Interactions ; immunology ; Humans ; Immune Evasion ; Immunity, Innate ; Interferon-gamma ; genetics ; immunology ; Lysosomes ; metabolism ; virology ; MCF-7 Cells ; Membrane Fusion ; Membrane Proteins ; antagonists & inhibitors ; genetics ; immunology ; Microtubule-Associated Proteins ; genetics ; immunology ; Papain ; genetics ; immunology ; Phagosomes ; metabolism ; virology ; RNA, Small Interfering ; genetics ; immunology ; Signal Transduction ; Virus Replication

As the first line of immune defense for Mycobacterium tuberculosis (Mtb), macrophages also provide a major habitat for Mtb to reside in the host for years. The battles between Mtb and macrophages have been constant since ancient times. Triggered upon Mtb infection, multiple cellular pathways in macrophages are activated to initiate a tailored immune response toward the invading pathogen and regulate the cellular fates of the host as well. Toll-like receptors (TLRs) expressed on macrophages can recognize pathogen-associated-molecular patterns (PAMPs) on Mtb and mediate the production of immune-regulatory cytokines such as tumor necrosis factor (TNF) and type I Interferons (IFNs). In addition, Vitamin D receptor (VDR) and Vitamin D-1-hydroxylase are up-regulated in Mtb-infected macrophages, by which Vitamin D participates in innate immune responses. The signaling pathways that involve TNF, type I IFNs and Vitamin D are inter-connected, which play critical roles in the regulation of necroptosis, apoptosis, and autophagy of the infected macrophages. This review article summarizes current knowledge about the interactions between Mtb and macrophages, focusing on cellular fates of the Mtb-infected macrophages and the regulatory molecules and cellular pathways involved in those processes.
Animals ; Apoptosis ; Autophagy ; Humans ; Interferon Type I ; metabolism ; Macrophages ; immunology ; metabolism ; Mycobacterium tuberculosis ; physiology ; Receptors, Calcitriol ; metabolism ; Steroid Hydroxylases ; metabolism ; Toll-Like Receptors ; metabolism ; Tuberculosis ; immunology ; metabolism ; pathology ; Tumor Necrosis Factors ; metabolism

Autophagy is a catabolic process including self-degradation of intracellular components via the lysosomal machinery. The biological behavior can be regarded as defense mechanism, maintaining the cell growth, metabolism and homeostasis etc. To date, plenty of autophagy related genes have been identified. In addition, it has been recognized that autophagy plays important roles in the context of virus infection: it can transport viruses from cytoplasm to lysosome to degrade viruses; it can transfer viral nucleic acid to intracellular sensors to activate innate immunity; it can also present viral antigens to MHC class II molecules to activate adaptive immune responses. Autophagy may serve as a double-edged sword to intracellular pathogens. On one side, autophagy may degrade and clear invading microorganisms by xenophagy; on the other side, some microorganisms may develop mechanisms to escape from autophagy for their survival. In this paper, the notion of autophay and the function of autophagy related genes are reviewed. Furthermore, the association of autophagy with a variety of viruses is discussed.
Animals ; Autophagy ; physiology ; Humans ; Virus Diseases ; immunology