• Molecules and Cells
• /
• 제43권1호
• /
• pp.10-22
• /
• 2020

Mitochondria have several quality control mechanisms by which they maintain cellular homeostasis and ensure that the molecular machinery is protected from stress. Mitophagy, selective autophagy of mitochondria, promotes mitochondrial quality control by inducing clearance of damaged mitochondria via the autophagic machinery. Accumulating evidence suggests that mitophagy is modulated by various microbial components in an attempt to affect the innate immune response to infection. In addition, mitophagy plays a key role in the regulation of inflammatory signaling, and mitochondrial danger signals such as mitochondrial DNA translocated into the cytosol can lead to exaggerated inflammatory responses. In this review, we present current knowledge on the functional aspects of mitophagy and its crosstalk with innate immune signaling during infection. A deeper understanding of the role of mitophagy could facilitate the development of more effective therapeutic strategies against various infections.

• Fisheries and Aquatic Sciences
• /
• 제13권4호
• /
• pp.343-349
• /
• 2010

The effects of osmotic stress on the non-specific immune response of Nile tilapia, Oreochromis niloticus, were investigated. Osmoregulatory mechanism of tilapia has been studied, but less information is available about innate immune response of O. niloticus faced with hyperosmolality. Acute osmotic stress was elicited by transferring tilapia from freshwater (FW) to 24 psu seawater (SW). Non-specific immune parameters including lysozyme activities of plasma and head kidney (HK), alternative complement pathway (ACP) activity in plasma, phagocytic capacities of spleen and HK immune cells, and respiratory burst activity of immune cells in both HK and spleen were analyzed. Lysozyme activities were increased at 1 h and 30 h after transfer to SW, but decreased at 10 h after SW transfer. Conversely, ACP activity increased 10 h after SW transfer. Phagocytic capacity increased slightly at 1 h and 5 h after SW transfer, and respiratory burst activity showed an increase in superoxide release at 10 h after SW transfer. Taken together, these results indicate that the exposure of tilapia to hyperosmotic conditions has immunostimulatory effects on cellular and humoral immune reactions.

• Journal of Microbiology and Biotechnology
• /
• 제31권2호
• /
• pp.226-232
• /
• 2021

Severe fever with thrombocytopenia syndrome virus (SFTSV) is an emerging phlebovirus of the Phenuiviridae family that has been circulating in the following Asian countries: Vietnam, Myanmar, Taiwan, China, Japan, and South Korea. Despite the increasing infection rates and relatively high mortality rate, there is limited information available regarding SFTSV pathogenesis. In addition, there are currently no vaccines or effective antiviral treatments available. Previous reports have shown that SFTSV suppresses the host immune response and its nonstructural proteins (NSs) function as an antagonist of type I interferon (IFN), whose induction is an essential part of the host defense system against viral infections. Given that SFTSV NSs suppress the innate immune response by inhibiting type I IFN, we investigated the mechanism utilized by SFTSV NSs to evade IFNmediated response. Our co-immunoprecipitation data suggest the interactions between NSs and retinoic acid inducible gene-I (RIG-I) or TANK binding kinase 1 (TBK1). Furthermore, confocal analysis indicates the ability of NSs to sequester RIG-I and related downstream molecules in the cytoplasmic structures called inclusion bodies (IBs). NSs are also capable of inhibiting TBK1-interferon regulatory factor 3 (IRF3) interaction, and therefore prevent the phosphorylation and nuclear translocation of IRF3 for the induction of type I IFN. The ability of SFTSV NSs to interact with and sequester TBK1 and IRF3 in IBs demonstrate an effective yet unique method utilized by SFTSV to evade and suppress host immunity.

• Toxicological Research
• /
• 제33권4호
• /
• pp.283-290
• /
• 2017

The host immune system is the first line of host defense, consisting mainly of innate and adaptive immunity. Immunity must be maintained, orchestrated, and harmonized, since overactivation of immune responses can lead to inflammation and autoimmune diseases, while immune deficiency can lead to infectious diseases. We investigated the regulation of innate and adaptive immune cell activation by Artemisia capillaris and its components (ursolic acid, hyperoside, scopoletin, and scopolin). Macrophage phagocytic activity was determined using fluorescently labeled Escherichia coli, as an indicator of innate immune activation. Concanavalin A (ConA)- and lipopolysaccharide (LPS)-induced splenocyte proliferation was analyzed as surrogate markers for cellular and humoral adaptive immunity, respectively. Neither A. capillaris water extract (WAC) nor ethanol extract (EAC) greatly inhibited macrophage phagocytic activity. In contrast, WAC suppressed ConA- and LPS-induced proliferation of primary mouse splenocytes in a dose-dependent manner. Similarly, EAC inhibited ConA- and LPS-induced splenocyte proliferation. Oral administration of WAC in mice decreased ConA- and LPS-induced splenocyte proliferation, while that of EAC suppressed LPS-induced splenocyte proliferation. Repeated administration of WAC in mice inhibited ConA- and LPS-induced splenocyte proliferation. Ursolic acid, scopoletin, and scopolin reduced ConA- and LPS-induced primary mouse splenocyte proliferation, while hyperoside did not show such activity. These results indicate that A. capillaris and its components, ursolic acid, scopoletin, and scopolin, suppress ConA- and LPS-induced adaptive immune cell activation. The results suggest that A. capillaris is useful as a regulator of adaptive immunity for diseases involving excessive immune response activation.

• 대한한의학회지
• /
• 제20권2호
• /
• pp.177-186
• /
• 1999

Okbyungpoongsan(OBPS) has long been known to have anti-allergic effect. In order to evaluate the influence on innate and specific immune response, the effects of OBPS on vascular permeability. hypersensitivities and phagocytic functions were measured. As the results, OBPS increased phagocytic activity of peritoneal macrophages in vitro and in vivo. But OBPS depressed formation of reactive oxygen intermediates(ROI) in vitro and in vivo, while the drug enhanced generation macrophages. Foot pad swelling in the mouse and contact hypersensitivity against dinitroflouorobenzene were decreased. OBPS had no effect on NK cells. But OBPS decreased vascular permeability induced by histamine without statistical significance. These results demonstrate that OBPS suppresses hypersensitivity reactions without affecting phagocytic functions and formation of ROI from macrophages. It also means that OBPS acts as a effective inducer to synthesis of nitric oxide which is effective for the infectious disease while it does damage to tissue less as it suppresses ROI, So we can conclude that OBPS could be used for the treatment of the disease related with immune function.

• IMMUNE NETWORK
• /
• 제16권4호
• /
• pp.211-218
• /
• 2016

Due to the increasing prevalence and number of life-threatening cases, food allergy has emerged as a major health concern. The classic immune response seen during food allergy is allergen-specific IgE sensitization and hypersensitivity reactions to foods occur in the effector phase with often severe and deleterious outcomes. Recent research has advanced understanding of the immunological mechanisms occurring during the effector phase of allergic reactions to ingested food. Therefore, this review will not only cover the mucosal immune system of the gastrointestinal tract and the immunological mechanisms underlying IgE-mediated food allergy, but will also introduce cells recently identified to have a role in the hypersensitivity reaction to food allergens. These include IL-9 producing mucosal mast cells (MMC9s) and type 2 innate lymphoid cells (ILC2s). The involvement of these cell types in potentiating the type 2 immune response and developing the anaphylactic response to food allergens will be discussed. In addition, it has become apparent that there is a collaboration between these cells that contributes to an individual's susceptibility to IgE-mediated food allergy.

• BMB Reports
• /
• 제47권4호
• /
• pp.184-191
• /
• 2014

Respiratory syncytial virus (RSV) is the leading cause of respiratory infection in infants and young children. Severe clinical manifestation of RSV infection is a bronchiolitis, which is common in infants under six months of age. Recently, RSV has been recognized as an important cause of respiratory infection in older populations with cardiovascular morbidity or immunocompromised patients. However, neither a vaccine nor an effective antiviral therapy is currently available. Moreover, the interaction between the host immune system and the RSV pathogen during an infection is not well understood. The innate immune system recognizes RSV through multiple mechanisms. The first innate immune RSV detectors are the pattern recognition receptors (PRRs), including toll-like receptors (TLRs), retinoic acid-inducible gene-I (RIG-I)-like receptors (RLRs), and nucleotide-biding oligomerization domain (NOD)-like receptors (NLRs). The following is a review of studies associated with various PRRs that are responsible for RSV virion recognition and subsequent induction of the antiviral immune response during RSV infection.

• 대한한방소아과학회지
• /
• 제8권1호
• /
• pp.39-58
• /
• 1994

Even though appropriate immune response is necessary for the survival of the individual, excessive or insufficient immune response might cause autoimmune or allergic disease respectively. So the immune response must be controlled to the degree that is beneficial for the well being of the individual. This study was undertaken to know the effects of Junsibaekchulsan(JB) on the immune system od the mouse. For the evalulation of the cell-mediated immunity(CMI), delayed-type hypersensitivity against dinitrofluorobenzene(DNFB) were measured, and humoral immunity, hemagglutinin and hemolysin titers against SRBCs(sheep red blood cells) were measured, and rosette formation of spleen cells with SRBCs were measured. For the evaluation of innate immunity, phagocytic activity of macrophages, natural killer cell activity, and reactive nitrogen and oxygen intermediates were measured. The results are as follows: 1. The administration of JB depressed the antibody formation (hemagglutinin and hemolysin) against SRBCs. 2. The administration of JB did not affect the delayed-type hypersensitivity against DNFB. 3. The administration of JB did not affect the cytotoxic activity of natural killer cells. 4. The administration of JB increased the phagocytic activity of macrophages. 5. The administration of JB increased the rosette formating cells of the spleen cells. 6. The exposure of JB induced the secretion of reactive nitrogen intermediates but administration of JB deperssed the production of reactive oxygen intermediates. Administration of JB selectively depressed the humoral immune response without affecting CMI and innate immunity. These results of JB on the immune system might be useful for the treatment of such.

• 대한한의학회지
• /
• 제18권2호
• /
• pp.43-57
• /
• 1997

It was claimed that the herbal medicine with the function of strengthening the body resistance exerts to enhance the immunity. And the medicine with the effect of eliminating the pathogenic factor is stated to inhibit the immune response. To evaluate the the effects of the herbal medicine on the immune response, the mice were administrated with the herbal medicine for 2 weeks. And the responses were analyzed. As the result, water extract of Radix Astragali, Fructus Psoraleae, Cortex Acanthopanacis, Semen Coicis, Herba Ecliptae, Spica Prunellae, and Radix Sophorae increased the ROI production, while Radix Tripterygia inhibited it. Phagocytic activity was increased after administration of Radix Astragal, Fructus Psoraleae, Cortex Acanthopanacis, Herba Ecliptae, Spica Prunellae and Radix Sophorae. NK cell activity was also significantly inhibited by Radix Tripterygia. Administration of Radix Astragali, Fructus Psoraleae, Cortex Acanthopanacis, Herba Ecliptae, Spica Prunellae and Semen Coicis enhanced the antibodies(hemagglutinin and hemolysin) formation and the appearance of rosette forming cells of the spleen, while Radix Sophorae and Radix Tripterygia decreased it. Radix Sophorae and Radix Tripterygia also decreased the allogenic immune response and mixed-lymphocyte reaction. And all the experimental herbs decreased contact hypersensitivity against dinitroflurobenzene. These results show Radix Astragali, Fructus Psoraleae, Spica Prunellae, Cortex Acanthopanacis, Semen Coicis and Herba Ecliptae enhanced innate immunity, humoral and cellular immune responses. However Radix Sophorae and Radix Tripterygia exert imunosuppressive action. Also these results indicate that the medicine with the action of the strengthening the body resistance enhances the immunity. And the the some of drugs belonging to the eliminating the pathogenic factor also increase the immune responses.

• IMMUNE NETWORK
• /
• 제14권3호
• /
• pp.128-137
• /
• 2014

Respiratory viruses can induce acute respiratory disease. Clinical symptoms and manifestations are dependent on interactions between the virus and host immune system. Dendritic cells (DCs), along with alveolar macrophages, constitute the first line of sentinel cells in the innate immune response against respiratory viral infection. DCs play an essential role in regulating the immune response by bridging innate and adaptive immunity. In the steady state, lung DCs can be subdivided into $CD103^+$ conventional DCs (cDCs), $CD11b^+$ cDCs, and plasmacytoid DCs (pDCs). In the inflammatory state, like a respiratory viral infection, monocyte-derived DCs (moDCs) are recruited to the lung. In inflammatory lung, discrimination between moDCs and $CD11b^+$ DCs in the inflamed lung has been a critical challenge in understanding their role in the antiviral response. In particular, $CD103^+$ cDCs migrate from the intraepithelial base to the draining mediastinal lymph nodes to primarily induce the $CD8^+$ T cell response against the invading virus. Lymphoid $CD8{\alpha}^+$ cDCs, which have a developmental relationship with $CD103^+$ cDCs, also play an important role in viral antigen presentation. Moreover, pDCs have been reported to promote an antiviral response by inducing type I interferon production rather than adaptive immunity. However, the role of these cells in respiratory infections remains unclear. These different DC subsets have functional specialization against respiratory viral infection. Under certain viral infection, contextually controlling the balance of these specialized DC subsets is important for an effective immune response and maintenance of homeostasis.