Hydrogel design to overcome thermal resistance and ROS detoxification in photothermal and photodynamic therapy of cancer.

Responsive heat resistance (by heat shock protein upregulation) and spontaneous reactive oxygen species (ROS) detoxification have been regarded as the major obstacles for photothermal/photodynamic therapy of cancer. To overcome the thermal resistance and improve ROS susceptibility in breast cancer therapy, Au ion-crosslinked hydrogels including indocyanine green (ICG) and polyphenol are devised. Au ion has been introduced for gel crosslinking (by catechol-Au3+ coordination), cellular glutathione depletion, and O2 production from cellular H2O2. ICG can generate singlet oxygen from O2 (for photodynamic therapy) and induce hyperthermia (for photothermal therapy) under the near-infrared laser exposure. (-)-Epigallocatechin gallate downregulates heat shock protein to overcome heat resistance during hyperthermia and exerts multiple anticancer functions in spite of its ironical antioxidant features. Those molecules are concinnously engaged in the hydrogel structure to offer fast gel transformation, syringe injection, self-restoration, and rheological tuning for augmented photo/chemotherapy of cancer. Intratumoral injection of multifunctional hydrogel efficiently suppressed the growth of primary breast cancer and completely eliminated the residual tumor mass. Proposed hydrogel system can be applied to tumor size reduction prior to surgery of breast cancer and the complete remission after its surgery.

Alum-tuned hyaluronic acid-based hydrogel with immune checkpoint inhibition for immunophoto therapy of cancer.

Alum-crosslinked hyaluronic acid-dopamine (HD) hydrogel containing indocyanine green (ICG) with anti-programmed cell death-1 (PD-1) antibody (Ab) administration was developed for immunophoto therapy of cancer. Alum modulates the rheological characteristics of hydrogel for enabling syringe injection, shear-thinning feature, and slower biodegradation. In addition, alum in HD-based hydrogel provided CD8+ T cell-mediated immune responses for cancer therapy. ICG in the hydrogel under near-infrared (NIR) light exposure may induce hyperthermia and generate singlet oxygen for selective cancer cell killing. HD/alum/ICG hydrogel injection with NIR laser irradiation elevated PD-1 level in CD8+ T cells. Administration of PD-1 Ab aiming at highly expressed PD-1 in T cells may amplify the anticancer efficacies of HD/alum/ICG hydrogel along with NIR laser. HD/alum/ICG hydrogel with NIR light may have both CD8+ T cell-linked immune responses and ICG-related photodynamic/photothermal effects. Additional injection of immune checkpoint inhibitor can ultimately suppress primary and distant tumor growth by combination with those therapeutic actions.

Methionine consumption by cancer cells drives a progressive upregulation of PD-1 expression in CD4 T cells.

Programmed cell death protein 1 (PD-1), expressed on tumor-infiltrating T cells, is a T cell exhaustion marker. The mechanisms underlying PD-1 upregulation in CD4 T cells remain unknown. Here we develop nutrient-deprived media and a conditional knockout female mouse model to study the mechanism underlying PD-1 upregulation. Reduced methionine increases PD-1 expression on CD4 T cells. The genetic ablation of SLC43A2 in cancer cells restores methionine metabolism in CD4 T cells, increasing the intracellular levels of S-adenosylmethionine and yielding H3K79me2. Reduced H3K79me2 due to methionine deprivation downregulates AMPK, upregulates PD-1 expression and impairs antitumor immunity in CD4 T cells. Methionine supplementation restores H3K79 methylation and AMPK expression, lowering PD-1 levels. AMPK-deficient CD4 T cells exhibit increased endoplasmic reticulum stress and Xbp1s transcript levels. Our results demonstrate that AMPK is a methionine-dependent regulator of the epigenetic control of PD-1 expression in CD4 T cells, a metabolic checkpoint for CD4 T cell exhaustion.

ERdj5 protects goblet cells from endoplasmic reticulum stress-mediated apoptosis under inflammatory conditions.

Endoplasmic reticulum stress is closely associated with the onset and progression of inflammatory bowel disease. ERdj5 is an endoplasmic reticulum-resident protein disulfide reductase that mediates the cleavage and degradation of misfolded proteins. Although ERdj5 expression is significantly higher in the colonic tissues of patients with inflammatory bowel disease than in healthy controls, its role in inflammatory bowel disease has not yet been reported. In the current study, we used ERdj5-knockout mice to investigate the potential roles of ERdj5 in inflammatory bowel disease. ERdj5 deficiency causes severe inflammation in mouse colitis models and weakens gut barrier function by increasing NF-κB-mediated inflammation. ERdj5 may not be indispensable for goblet cell function under steady-state conditions, but its deficiency induces goblet cell apoptosis under inflammatory conditions. Treatment of ERdj5-knockout mice with the chemical chaperone ursodeoxycholic acid ameliorated severe colitis by reducing endoplasmic reticulum stress. These findings highlight the important role of ERdj5 in preserving goblet cell viability and function by resolving endoplasmic reticulum stress.

Obesity Exacerbates Coxsackievirus Infection via Lipid-Induced Mitochondrial Reactive Oxygen Species Generation.

Coxsackievirus B3 (CVB3) infection causes acute pancreatitis and myocarditis. However, its pathophysiological mechanism is unclear. Here, we investigated how lipid metabolism is associated with exacerbation of CVB3 pathology using high-fat diet (HFD)-induced obese mice. Mice were intraperitoneally inoculated with 1×106 pfu/mouse of CVB3 after being fed a control or HFD to induce obesity. Mice were treated with mitoquinone (MitoQ) to reduce the level of mitochondrial ROS (mtROS). In obese mice, lipotoxicity of white adipose tissue-induced inflammation caused increased replication of CVB3 and mortality. The coxsackievirus adenovirus receptor increased under obese conditions, facilitating CVB3 replication in vitro. However, lipid-treated cells with receptor-specific inhibitors did not reduce CVB3 replication. In addition, lipid treatment increased mitochondria-derived vesicle formation and the number of multivesicular bodies. Alternatively, we found that inhibition of lipid-induced mtROS decreased viral replication. Notably, HFD-fed mice were more susceptible to CVB3-induced mortality in association with increased levels of CVB3 replication in adipose tissue, which was ameliorated by administration of the mtROS inhibitor, MitoQ. These results suggest that mtROS inhibitors can be used as potential treatments for CVB3 infection.

Bispecific Antibody-Bound T Cells as a Novel Anticancer Immunotherapy.

Chimeric antigen receptor T (CAR-T) cell therapy is one of the promising anticancer treatments. It shows a high overall response rate with complete response to blood cancer. However, there is a limitation to solid tumor treatment. Additionally, this currently approved therapy exhibits side effects such as cytokine release syndrome and neurotoxicity. Alternatively, bispecific antibody is an innovative therapeutic tool that simultaneously engages specific immune cells to disease-related target cells. Since programmed death ligand 1 (PD-L1) is an immune checkpoint molecule highly expressed in some cancer cells, in the current study, we generated αCD3xαPD-L1 bispecific antibody (BiTE) which can engage T cells to PD-L1+ cancer cells. We observed that the BiTE-bound OT-1 T cells effectively killed cancer cells in vitro and in vivo. They substantially increased the recruitment of effector memory CD8+ T cells having CD8+CD44+CD62Llow phenotype in tumor. Interestingly, we also observed that BiTE-bound polyclonal T cells showed highly efficacious tumor killing activity in vivo in comparison with the direct intravenous treatment of bispecific antibody, suggesting that PD-L1-directed migration and engagement of activated T cells might increase cancer cell killing. Additionally, BiTE-bound CAR-T cells which targets human Her-2/neu exhibited enhanced killing effect on Her-2-expressing cancer cells in vivo, suggesting that this could be a novel therapeutic regimen. Collectively, our results suggested that engaging activated T cells with cancer cells using αCD3xαPD-L1 BiTE could be an innovative next generation anticancer therapy which exerts simultaneous inhibitory functions on PD-L1 as well as increasing the infiltration of activated T cells having effector memory phenotype in tumor site.

Loss of ERdj5 exacerbates oxidative stress in mice with alcoholic liver disease via suppressing Nrf2.

Alcoholic liver disease is the major cause of chronic liver diseases. Excessive alcohol intake results in endoplasmic reticulum (ER) stress. ERdj5, a member of DNAJ family, is an ER-resident chaperone protein, whose role in alcoholic liver disease remains to be investigated. In this study, we aim to address the effect of ERdj5 on alcoholic liver disease and the underlying mechanism. Hepatic Dnajc10 (ERdj5) mRNA expression was elevated in both human and mouse alcoholic hepatitis. In mice subjected to chronic and binge ethanol feeding, ERdj5 levels were also markedly increased. Hepatic Dnajc10 correlated with Xbp1s mRNA. Tunicamycin, an ER stress inducer, increased ERdj5 levels. Dnajc10 knockout mice exhibited exacerbated alcohol-induced liver injury and hepatic steatosis. However, the macrophage numbers and chemokine levels were similar to those in wild-type mice. Depletion of Dnajc10 promoted oxidative stress. Ethanol feeding increased hepatic H2O2 levels, and these were further increased in Dnajc10 knockout mice. Additionally, Dnajc10-deficient hepatocytes produced large amounts of reactive oxygen species. Notably, Nrf2, a central regulator of oxidative stress, was decreased by depletion of Dnajc10 in the nuclear fraction of ethanol-treated mouse liver. Consistently, liver tissues from ethanol-fed Dnajc10 knockout mice had reduced expression of downstream antioxidant genes. Furthermore, hepatic glutathione content in the liver of knockout mice declined compared to wild-type mice. In conclusion, our results demonstrate that ethanol-induced ERdj5 may regulate the Nrf2 pathway and glutathione contents, and have protective effects on liver damage and alcohol-mediated oxidative stress in mice. These suggest that ERdj5 has the potential to protect against alcoholic liver disease.

AMPK promotes antitumor immunity by downregulating PD-1 in regulatory T cells via the HMGCR/p38 signaling pathway.

BACKGROUND: AMP-activated protein kinase (AMPK) is a metabolic sensor that maintains energy homeostasis. AMPK functions as a tumor suppressor in different cancers; however, its role in regulating antitumor immunity, particularly the function of regulatory T cells (Tregs), is poorly defined. METHODS: AMPKα1fl/flFoxp3YFP-Cre, Foxp3YFP-Cre, Rag1-/-, and C57BL/6 J mice were used for our research. Flow cytometry and cell sorting, western blotting, immuno-precipitation, immuno-fluorescence, glycolysis assay, and qRT-PCR were used to investigate the role of AMPK in suppressing programmed cell death 1 (PD-1) expression and for mechanistic investigation. RESULTS: The deletion of the AMPKα1 subunit in Tregs accelerates tumor growth by increasing the expression of PD-1. Metabolically, loss of AMPK in Tregs promotes glycolysis and the expression of 3-hydroxy-3-methylglutaryl-CoA reductase (HMGCR), a key enzyme of the mevalonate pathway. Mechanistically, AMPK activates the p38 mitogen-activated protein kinase (MAPK) that phosphorylates glycogen synthase kinase-3ß (GSK-3ß), inhibiting the expression of PD-1 in Tregs. CONCLUSION: Our study identified an AMPK regulatory mechanism of PD-1 expression via the HMGCR/p38 MAPK/GSK3ß signaling pathway. We propose that the AMPK activator can display synergic antitumor effect in murine tumor models, supporting their potential clinical use when combined with anti-PD-1 antibody, anti-CTLA-4 antibody, or a HMGCR inhibitor.

A Novel Anti-PD-L1 Antibody Exhibits Antitumor Effects on Multiple Myeloma in Murine Models via Antibody-Dependent Cellular Cytotoxicity.

Multiple myeloma is a malignant cancer of plasma cells. Despite recent progress with immunomodulatory drugs and proteasome inhibitors, it remains an incurable disease that requires other strategies to overcome its recurrence and non-response. Based on the high expression levels of programmed death-ligand 1 (PD-L1) in human multiple myeloma isolated from bone marrow and the murine myeloma cell lines, NS-1 and MOPC-315, we propose PD-L1 molecule as a target of anti-multiple myeloma therapy. We developed a novel anti-PD-L1 antibody containing a murine immunoglobulin G subclass 2a (IgG2a) fragment crystallizable (Fc) domain that can induce antibody-dependent cellular cytotoxicity. The newly developed anti-PD-L1 antibody showed significant antitumor effects against multiple myeloma in mice subcutaneously, intraperitoneally, or intravenously inoculated with NS-1 and MOPC-315 cells. The anti-PD-L1 effects on multiple myeloma may be related to a decrease in the immunosuppressive myeloid-derived suppressor cells (MDSCs), but there were no changes in the splenic MDSCs after combined treatment with lenalidomide and the anti-PD-L1 antibody. Interestingly, the newly developed anti-PD-L1 antibody can induce antibody-dependent cellular cytotoxicity in the myeloma cells, which differs from the existing anti-PD-L1 antibodies. Collectively, we have developed a new anti-PD-L1 antibody that binds to mouse and human PD-L1 and demonstrated the antitumor effects of the antibody in several syngeneic murine myeloma models. Thus, PD-L1 is a promising target to treat multiple myeloma, and the novel anti-PD-L1 antibody may be an effective anti-myeloma drug via antibody-dependent cellular cytotoxicity effects.

Lysophosphatidylcholine Enhances Bactericidal Activity by Promoting Phagosome Maturation via the Activation of the NF-κB Pathway during Salmonella Infection in Mouse Macrophages.

Salmonella enterica serovar Typhimurium (S. Typhimurium) is a facultative intracellular pathogen that causes salmonellosis and mortality worldwide. S. Typhimurium infects macrophages and survives within phagosomes by avoiding the phagosome-lysosome fusion system. Phagosomes sequentially acquire different Rab GTPases during maturation and eventually fuse with acidic lysosomes. Lysophosphatidylcholine (LPC) is a bioactive lipid that is associated with the generation of chemoattractants and reactive oxygen species (ROS). In our previous study, LPC controlled the intracellular growth of Mycobacterium tuberculosis by promoting phagosome maturation. In this study, to verify whether LPC enhances phagosome maturation and regulates the intracellular growth of S. Typhimurium, macrophages were infected with S. Typhimurium. LPC decreased the intracellular bacterial burden, but it did not induce cytotoxicity in S. Typhimuriuminfected cells. In addition, combined administration of LPC and antibiotic significantly reduced the bacterial burden in the spleen and the liver. The ratios of the colocalization of intracellular S. Typhimurium with phagosome maturation markers, such as early endosome antigen 1 (EEA1) and lysosome-associated membrane protein 1 (LAMP-1), were significantly increased in LPC-treated cells. The expression level of cleaved cathepsin D was rapidly increased in LPCtreated cells during S. Typhimurium infection. Treatment with LPC enhanced ROS production, but it did not affect nitric oxide production in S. Typhimurium-infected cells. LPC also rapidly triggered the phosphorylation of IκBα during S. Typhimurium infection. These results suggest that LPC can improve phagosome maturation via ROS-induced activation of NF-κB pathway and thus may be developed as a therapeutic agent to control S. Typhimurium growth.

Morin Hydrate Inhibits Influenza Virus entry into Host Cells and Has Anti-inflammatory Effect in Influenza-infected Mice.

Influenza virus is the major cause of seasonal and pandemic flu. Currently, oseltamivir, a potent and selective inhibitor of neuraminidase of influenza A and B viruses, is the drug of choice for treating patients with influenza virus infection. However, recent emergence of oseltamivir-resistant influenza viruses has limited its efficacy. Morin hydrate (3,5,7,2',4'-pentahydroxyflavone) is a flavonoid isolated from Morus alba L. It has antioxidant, anti-inflammatory, neuroprotective, and anticancer effects partly by the inhibition of the NF-кB signaling pathway. However, its effects on influenza virus have not been studied. We evaluated the antiviral activity of morin hydrate against influenza A/Puerto Rico/8/1934 (A/PR/8; H1N1) and oseltamivir-resistant A/PR/8 influenza viruses in vitro. To determine its mode of action, we carried out time course experiments, and time of addition, hemolysis inhibition, and hemagglutination assays. The effects of the co-administration of morin hydrate and oseltamivir were assessed using the murine model of A/PR/8 infection. We found that morin hydrate reduced hemagglutination by A/PR/8 in vitro. It alleviated the symptoms of A/PR/8-infection, and reduced the levels of pro-inflammatory cytokines and chemokines, such as TNF-α and CCL2, in infected mice. Co-administration of morin hydrate and oseltamivir phosphate reduced the virus titers and attenuated pulmonary inflammation. Our results suggest that morin hydrate exhibits antiviral activity by inhibiting the entry of the virus.

Plasmacytoid dendritic cells regulate colitis-associated tumorigenesis by controlling myeloid-derived suppressor cell infiltration.

Toll-like receptor (TLR)3 and TLR7 are important for stimulating plasmacytoid dendritic cells (pDCs), which secrete type I interferon. Mice deficient for TLR3 and TLR7 (TLR3-/-TLR7-/-) reportedly exhibit deteriorated colitis because of impaired pDCs. However, the role of pDCs in tumorigenesis-associated inflammation progression has not been studied. We treated wild-type or TLR3-/-TLR7-/- mice with dextran sulfate sodium (DSS) and/or azoxymethane (AOM) and examined colon mucosa, measured body weight and colon length of mice, and examined pDC and myeloid-derived suppressor cell (MDSC) accumulation. Further, we depleted pDCs in AOM/DSS-treated wild-type mice by treating them with anti-PDCA-1 antibodies. We found that MDSCs significantly increased, while pDCs decreased in TLR3-/-TLR7-/- mice. Moreover, TLR3-/-TLR7-/- mice developed colitis-associated colon cancer following AOM/DSS treatment. Additionally, we showed that a defect in TLR7 of pDCs is responsible for the aggravation of colitis-associated colon cancer. Further, we showed that TLR7 ligand mitigates colitis-associated colon cancer. Collectively, our results demonstrate that gut pDCs play a crucial role in reducing colorectal cancer development via the regulation of infiltrating MDSCs.

IκBζ controls NLRP3 inflammasome activation via upregulation of the Nlrp3 gene.

Inflammasome activation induces the maturation and secretion of interleukin (IL)-1ß and -18, and is dependent on NF-κB signaling to induce the transcription of the inflammasome components, called the priming step. This study elucidated the role of IκBζ, an atypical IκBs (inhibitor of κB) and a coactivator of NF-κB target genes, on the activation of inflammasome. Bone marrow-derived macrophages (BMDMs) that originated from IκBζ-encoding Nfkbiz gene depletion mice presented a defect in NLRP3 inflammasome activation. In addition, the Nfkbiz+/- and Nfkbiz-/- mice significantly attenuated serum IL-1ß secretion in response to a monosodium urate injection, a NLRP3 trigger, when compared with Nfkbiz-+/+ mice. The lack of IκBζ in BMDMs produced a disability in the expression of Nlrp3 and pro-Il1ß mRNAs during the priming step. In addition, ectopic IκBζ expression enhanced the Nlrp3 promoter activity, and Nlrp3 and pro-Il1ß transcription. Overall, IκBζ controlled the activation of NLRP3 inflammasome by upregulating the Nlrp3 gene during the priming step.

B Cell-Based Vaccine Transduced With ESAT6-Expressing Vaccinia Virus and Presenting α-Galactosylceramide Is a Novel Vaccine Candidate Against ESAT6-Expressing Mycobacterial Diseases.

Early secretory antigenic target-6 (ESAT6) is a potent immunogenic antigen expressed in Mycobacterium tuberculosis as well as in some non-tuberculous mycobacteria (NTM), such as M. kansasii. M. kansasii is one of the most clinically relevant species of NTM that causes mycobacterial lung disease, which is clinically indistinguishable from tuberculosis. In the current study, we designed a novel cell-based vaccine using B cells that were transduced with vaccinia virus expressing ESAT6 (vacESAT6), and presenting α-galactosylceramide (αGC), a ligand of invariant NKT cells. We found that B cells loaded with αGC had increased levels of CD80 and CD86 after in vitro stimulation with NKT cells. Immunization of mice with B/αGC/vacESAT6 induced CD4+ T cells producing TNF-α and IFN-γ in response to heat-killed M. tuberculosis. Immunization of mice with B/αGC/vacESAT6 ameliorated severe lung inflammation caused by M. kansasii infection. We also confirmed that immunization with B/αGC/vacESAT6 reduced M. kansasii bacterial burden in the lungs. In addition, therapeutic administration of B/αGC/vacESAT6 increased IFN-γ+ CD4+ T cells and inhibited the progression of lung pathology caused by M. kansasii infection. Thus, B/αGC/vacESAT6 could be a potent vaccine candidate for the prevention and treatment of ESAT6-expressing mycobacterial infection caused by M. kansasii.

IκBζ facilitates protective immunity against Salmonella infection via Th1 differentiation and IgG production.

Inhibitor of kappa B (IκB)-ζ transcription is rapidly induced by stimulation with TLR ligands and IL-1. Despite high IκBζ expression in inflammation sites, the association of IκBζ with host defence via systemic immune responses against bacterial infection remains unclear. Oral immunisation with a recombinant attenuated Salmonella vaccine (RASV) strain did not protect IκBζ-deficient mice against a lethal Salmonella challenge. IκBζ-deficient mice failed to produce Salmonella LPS-specific IgG, especially IgG2a, although inflammatory cytokine production and immune cell infiltration into the liver increased after oral RASV administration. Moreover, IκBζ-deficient mice exhibited enhanced splenic germinal centre reactions followed by increased total IgG production, despite IκBζ-deficient B cells having an intrinsic antibody class switching defect. IκBζ-deficient CD4+ T cells poorly differentiated into Th1 cells. IFN-γ production by CD4+ T cells from IκBζ-deficient mice immunised with RASV significantly decreased after restimulation with heat-killed RASV in vitro, suggesting that IκBζ-deficient mice failed to mount protective immune responses against Salmonella infection because of insufficient Th1 and IgG production. Therefore, IκBζ is crucial in protecting against Salmonella infection by inducing Th1 differentiation followed by IgG production.

Manassantin B shows antiviral activity against coxsackievirus B3 infection by activation of the STING/TBK-1/IRF3 signalling pathway.

Coxsackievirus B3 (CVB3) is an important human pathogen associated with the development of acute pancreatitis, myocarditis, and type 1 diabetes. Currently, no vaccines or antiviral therapeutics are approved for the prevention and treatment of CVB3 infection. We found that Saururus chinensis Baill extract showed critical antiviral activity against CVB3 infection in vitro. Further, manassantin B inhibited replication of CVB3 and suppressed CVB3 VP1 protein expression in vitro. Additionally, oral administration of manassantin B in mice attenuated CVB3 infection-associated symptoms by reducing systemic production of inflammatory cytokines and chemokines including TNF-α, IL-6, IFN-γ, CCL2, and CXCL-1. We found that the antiviral activity of manassantin B is associated with increased levels of mitochondrial ROS (mROS). Inhibition of mROS generation attenuated the antiviral activity of manassantin B in vitro. Interestingly, we found that manassantin B also induced cytosolic release of mitochondrial DNA based on cytochrome C oxidase DNA levels. We further confirmed that STING and IRF-3 expression and STING and TBK-1 phosphorylation were increased by manassantin B treatment in CVB3-infected cells. Collectively, these results suggest that manassantin B exerts antiviral activity against CVB3 through activation of the STING/TKB-1/IRF3 antiviral pathway and increased production of mROS.

Antiviral and Anti-Inflammatory Activities of Pochonin D, a Heat Shock Protein 90 Inhibitor, against Rhinovirus Infection.

Human rhinoviruses (HRV) are one of the major causes of common cold in humans and are also associated with acute asthma and bronchial illness. Heat-shock protein 90 (Hsp90), a molecular chaperone, is an important host factor for the replication of single-strand RNA viruses. In the current study, we examined the effect of the Hsp90 inhibitor pochonin D, in vitro and in vivo, using a murine model of human rhinovirus type 1B (HRV1B) infection. Our data suggested that Hsp90 inhibition significantly reduced the inflammatory cytokine production and lung damage caused by HRV1B infection. The viral titer was significantly lowered in HRV1B-infected lungs and in Hela cells upon treatment with pochonin D. Infiltration of innate immune cells including granulocytes and monocytes was also reduced in the bronchoalveolar lavage (BAL) by pochonin D treatment after HRV1B infection. Histological analysis of the lung and respiratory tract showed that pochonin D protected the mice from HRV1B infection. Collectively, our results suggest that the Hsp90 inhibitor, pochonin D, could be an attractive antiviral therapeutic for treating HRV infection.

Development of New Preventive and Therapeutic Vaccines for Tuberculosis.

Tuberculosis (TB) is a contagious disease that has been responsible for the death of one billion people in the last 200 years. Until now, the only vaccine approved for the prevention of TB is Bacillus Calmette-Guérin (BCG), which is prepared by attenuating Mycobacterium bovis. However, one of the limitations of BCG is that its preventive effect against pulmonary TB varies from person to person. Therefore, there arises a need for a new TB vaccine to replace or supplement BCG. In this review, we have summarized the findings of current clinical trials on preventive and therapeutic TB vaccine candidates. In addition, we have discussed a novel vaccination approach using the cell-based vaccine presenting early secretory antigenic target-6 (ESAT-6), which is a potent immunogenic antigen. The role of ESAT-6 in hosts has also been described.

Antiviral and anti-inflammatory activity of budesonide against human rhinovirus infection mediated via autophagy activation.

Human rhinovirus (HRV) infection causes more than 80% of all common colds and is associated with severe complications in patients with asthma and chronic obstructive pulmonary disease. To identify antiviral drug against HRV infection, we screened 800 FDA-approved drugs and found budesonide as one of the possible drug candidates. Budesonide is a corticosteroid, which is commonly used to prevent exacerbation of asthma and symptoms of common cold. Budesonide specifically protects host cells from cytotoxicity following HRV infection, which depend on the expression of glucocorticoid receptor. Intranasal administration of budesonide lowered the pulmonary HRV load and the levels of IL-1ß cytokine leading to decreased lung inflammation. Budesonide regulates IL-1ß production following HRV infection independent of inflammasome activation. Instead, budesonide induces mitochondrial reactive oxygen species followed by activation of autophagy. Further, the inhibition of autophagy following chloroquine or bafilomycin A1 treatment reduced the anti-viral effect of budesonide against HRV, suggesting that the antiviral activity of budesonide was mediated via autophagy. The results suggest that budesonide represents a promising antiviral and anti-inflammatory drug candidate for the treatment of human rhinovirus infection.