• Title/Summary/Keyword: immune activation

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Th17 Cell and Inflammatory Infiltrate Interactions in Cutaneous Leishmaniasis: Unraveling Immunopathogenic Mechanisms

  • Abraham U. Morales-Primo;Ingeborg Becker;Claudia Patricia Pedraza-Zamora;Jaime Zamora-Chimal
    • IMMUNE NETWORK
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    • v.24 no.2
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    • pp.14.1-14.26
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    • 2024
  • The inflammatory response during cutaneous leishmaniasis (CL) involves immune and non-immune cell cooperation to contain and eliminate Leishmania parasites. The orchestration of these responses is coordinated primarily by CD4+ T cells; however, the disease outcome depends on the Th cell predominant phenotype. Although Th1 and Th2 phenotypes are the most addressed as steers for the resolution or perpetuation of the disease, Th17 cell activities, especially IL-17 release, are recognized to be vital during CL development. Th17 cells perform vital functions during both acute and chronic phases of CL. Overall, Th17 cells induce the migration of phagocytes (neutrophils, macrophages) to the infection site and CD8+ T cells and NK cell activation. They also provoke granzyme and perforin secretion from CD8+ T cells, macrophage differentiation towards an M2 phenotype, and expansion of B and Treg cells. Likewise, immune cells from the inflammatory infiltrate have modulatory activities over Th17 cells involving their differentiation from naive CD4+ T cells and further expansion by generating a microenvironment rich in optimal cytokines such as IL-1β, TGF-β, IL-6, and IL-21. Th17 cell activities and synergies are crucial for the resistance of the infection during the early and acute stages; however, if unchecked, Th17 cells might lead to a chronic stage. This review discusses the synergies between Th17 cells and the inflammatory infiltrate and how these interactions might destine the course of CL.

Enriching CCL3 in the Tumor Microenvironment Facilitates T cell Responses and Improves the Efficacy of Anti-PD-1 Therapy

  • Tae Gun Kang;Hyo Jin Park;Jihyun Moon;June Hyung Lee;Sang-Jun Ha
    • IMMUNE NETWORK
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    • v.21 no.3
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    • pp.23.1-23.16
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    • 2021
  • Chemokines are key factors that influence the migration and maintenance of relevant immune cells into an infected tissue or a tumor microenvironment. Therefore, it is believed that the controlled administration of chemokines in the tumor microenvironment may be an effective immunotherapy against cancer. Previous studies have shown that CCL3, also known as macrophage inflammatory protein 1-alpha, facilitates the recruitment of dendritic cells (DCs) for the presentation of tumor Ags and promotes T cell activation. Here, we investigated the role of CCL3 in regulating the tumor microenvironment using a syngeneic mouse tumor model. We observed that MC38 tumors overexpressing CCL3 (CCL3-OE) showed rapid regression compared with the wild type MC38 tumors. Additionally, these CCL3-OE tumors showed an increase in the proliferative and functional tumor-infiltrating T cells. Furthermore, PD-1 immune checkpoint blockade accelerated tumor regression in the CCL3-OE tumor microenvironment. Next, we generated a modified CCL3 protein for pre-clinical use by fusing recombinant CCL3 (rCCL3) with a non-cytolytic hybrid Fc (HyFc). Administering a controlled dose of rCCL3-HyFc via subcutaneous injections near tumors was effective in tumor regression and improved survival along with activated myeloid cells and augmented T cell responses. Furthermore, combination therapy of rCCL3-HyFc with PD-1 blockade exhibited prominent effect to tumor regression. Collectively, our findings demonstrate that appropriate concentrations of CCL3 in the tumor microenvironment would be an effective adjuvant to promote anti-tumor immune responses, and suggest that administering a long-lasting form of CCL3 in combination with PD-1 blockers can have clinical applications in cancer immunotherapy.

Bordetella bronchiseptica is a potent and safe adjuvant that enhances the antigen-presenting capability of dendritic cells

  • Lee, You-Jeong;Han, Yong;Joo, Hong-Gu
    • The Korean Journal of Physiology and Pharmacology
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    • v.24 no.1
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    • pp.47-52
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    • 2020
  • We previously demonstrated that Bordetella bronchiseptica (B. bronchiseptica) antigen (Ag) enhances the Mycoplasma hyopneumoniae Ag-specific immune response. The focus of this study was whether acellular bacterin of B. bronchiseptica could be used as an adjuvant to increase antigen-presenting capability of dendritic cells (DCs) by increasing the level of activation. The metabolic activity of DCs was increased by B. bronchiseptica, similar to lipopolysaccharide (LPS). Flow cytometry analysis revealed that B. bronchiseptica increases the expression of major histocompatibility complex class-2, cluster of differentiation (CD)40, CD54, and CD86 which are closely related to DC-mediated immune responses. B. bronchiseptica enhanced the production of cytokines related to adaptive immune responses. Furthermore, the survival rate of B. bronchiseptica-injected groups was 100% at 15 and 20 mg/kg doses, whereas that of LPS-injected groups was only 20%, 0% at 15 and 20 mg/kg doses respectively, and so B. bronchiseptica is likely to be safer than LPS. Taken together, these results indicate that B. bronchiseptica can be used as an adjuvant to enhance the antigen-presenting capability of DCs. B. bronchiseptica is a candidate for producing vaccines, especially in case of DC-mediating efficacy and safety demands. This study provides researchers and clinicians with valuable information regarding the usage of B. bronchiseptica as a safe bacteria-derived immunostimulating agent for developing efficient vaccines.

Co-stimulation of TLR4 and Dectin-1 Induces the Production of Inflammatory Cytokines but not TGF-${\beta}$ for Th17 Cell Differentiation

  • Chang, JiHoon;Kim, Byeong Mo;Chang, Cheong-Hee
    • IMMUNE NETWORK
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    • v.14 no.1
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    • pp.30-37
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    • 2014
  • Collaboration of TLR and non-TLR pathways in innate immune cells, which acts in concert for the induction of inflammatory cytokines, can mount a specific adaptive immune response tailored to a pathogen. Here, we show that murine DC produced increased IL-23 and IL-6 when they were treated with LPS together with curdlan that activates TLR4 and dectin-1, respectively. We also found that the induction of the inflammatory cytokine production by LPS and curdlan requires activation of IKK. However, the same treatment did not induce DC to produce a sufficient amount of TGF-${\beta}$. As a result, the conditioned media from DC treated with LPS and curdlan was not able to direct $CD4^+$ T cells to Th17 cells. Addition of TGF-${\beta}$ but not IL-6 or IL-$1{\beta}$ was able to promote IL-17 production from $CD4^+$ T cells. Our results showed that although signaling mediated by LPS together with curdlan is a potent stimulator of DC to secrete many pro-inflammatory cytokines, TGF-${\beta}$ production is a limiting factor for promoting Th17 immunity.

Contribution of TLR2 to the Initiation of Ganglioside-triggered Inflammatory Signaling

  • Yoon, Hee Jung;Jeon, Sae Bom;Suk, Kyoungho;Choi, Dong-Kug;Hong, Young-Joon;Park, Eun Jung
    • Molecules and Cells
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    • v.25 no.1
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    • pp.99-104
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    • 2008
  • Gangliosides, sialic acid-containing glycosphingolipids, are implicated in many neuronal diseases, but the precise molecular mechanisms underlying their pathological activities are poorly understood. Here we report that TLR2 participates in the initiation of ganglioside-triggered inflammatory signaling responses. Using FACS analysis and immunofluorescence microscopy, we found that gangliosides rapidly enhanced the cell surface expression of TLR2 in microglia, while reducing that of TLR4. The ganglioside-dependent increase of TLR2 expression was also observed at the messenger and protein levels. We also showed that gangliosides stimulate the interaction of TLR2 with Myd88, an adaptor for TLRs, and obtained evidence that lipid raft formation is closely associated with the ganglioside-induced activation of TLR2 and subsequent inflammatory signaling. These results collectively suggest that TLR2 contributes to the ability of gangliosides to cause inflammatory conditions in the brain.

Effects of Job's Tears(Yul-Moo) Extracts on Mouse Splenocyte and Macrophage Cell Activation (율무 추출물의 마우스 비장세포와 대식세포 활성 효과)

  • Ryu, Hye-Sook
    • The Korean Journal of Food And Nutrition
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    • v.21 no.1
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    • pp.1-6
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    • 2008
  • Job's Tears(Yul-Moo) is a grass crop long-used as a traditional medicine; it is also a nourishing food. There are reports of its anti-inflammatory, stomachic, antiallergic activity, and antispastic effects and Job's Tears has been used in China to treat rheumatism, and neuralgia although its warts, rheumanism remains unclear. Thus, the present study was performed to investigate the in vitro effect of Job's Tears extracts on immune function. Here mouse splenocyte proliferation and cytokine production$(IL-1{\beta},\;IL-6,\;TNF-{\alpha})$ by peritoneal macrophages cultured with ethanol and water extracts of Job's Tears were examined. splenocytes proliferation increased with Job's Tears water extracts supplement at concentrations investigated The cytokine production$(IL-1{\beta},\;IL-6,\;TNF-{\alpha})$ by ELISA using a cytokine kit And $IL-1{\beta}$, IL-6 and $TNF-{\alpha}$ production increased water extracts supplementation. This in vitro study suggests that supplementation with Job's Tears water extracts may enhance immune function by regulating the splenocyte proliferation and enhancing cytokine production of activated macrophages.

CTLA-4-Tg/CD-28-KO Mice Exhibit Reduced T Cell Proliferation in vivo Compared to CD-28-KO Mice in a Graft-versus-host Disease Model

  • Yoo, Jong-Sun;Lee, Yun-Jung;Yoon, Joo-Won;Hyung, Kyeong-Eun;Hwang, Kwang-Woo
    • The Korean Journal of Physiology and Pharmacology
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    • v.16 no.5
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    • pp.349-353
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    • 2012
  • Activated T cells express inhibitory receptors such as CTLA-4 that can downregulate immune responses. Blockade of or genetic deficiency in CTLA-4 can result in autoimmunity. Therefore, strategies to increase the inhibitory function of CTLA-4 may be attractive in settings of undesirable T cell responses such as autoimmunity or transplant rejection. We have tested the hypothesis that transgenic constitutive expression of CTLA-4 can further attenuate immune responses when compared with normal inducible expression. Our results indicate that transgenic expression of CTLA-4 in mouse T cells (CTLA-4-Tg T cells) results in reduced cell cycle progression and increased apoptosis of TCR-stimulated T cells. CTLA-4-Tg T cells display reduced T cell proliferation in an in vivo model of graft versus host disease (GVHD). These results further our understanding of how CTLA-4 can be manipulated to inhibit immune responses and may help development of new therapeutic strategies for clinical settings of autoimmunity and transplantation.

Immunomodulatory effects of fermented Platycodon grandiflorum extract through NF-κB signaling in RAW 264.7 cells

  • Park, Eun-Jung;Lee, Hae-Jeung
    • Nutrition Research and Practice
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    • v.14 no.5
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    • pp.453-462
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    • 2020
  • BACKGROUND/OBJECTIVES: Platycodon grandiflorum (PG), an oriental herbal medicine, has been known to improve liver function, and has both anti-inflammatory and antimicrobial properties. However, little is known about the immune-enhancing effects of PG and its mechanism. In this study, we aimed to investigate whether fermented PG extract (FPGE), which has increased platycodin D content, activates the immune response in a murine macrophage cell line, RAW 264.7. MATERIALS/METHODS: Cell viability was determined by Cell Counting Kit-8 assay and the nitric oxide (NO) levels were measured using Griess reagent. Cytokine messenger RNA levels of were monitored by quantitative reverse transcription polymerase chain reaction. To investigate the molecular mechanisms underlying immunomodulatory actions of FPGE in RAW 264.7 cells, we have conducted luciferase reporter gene assay and western blotting. RESULTS: We found that FPGE treatment induced macrophage cell proliferation in a dose-dependent manner. FPGE also modulated the expression of NO and pro-inflammatory cytokines, such as tumor necrosis factor-α, interleukin (IL)-1β, and IL-6. The activation and phosphorylation levels of nuclear factor kappa B (NF-κB) were increased by FPGE treatment. Moreover, 5-aminoimidazole-4-carboxamide ribonucleotide, an activator of AMP-activated kinase (AMPK), significantly reduced both lipopolysaccharides- and FPGE-induced NF-κB reporter gene activity. CONCLUSIONS: Taken together, our findings suggest that FPGE may be a novel immune-enhancing agent acting via AMPK-NF-κB signaling pathway.

The inhibitory effects of Gami-Phedoc-San on TNF-α, IL-1β and IFN-γ secretion from human monocytes

  • Kim Mi-Sun;Lee Eun-Hee;Choung Se-Young
    • Advances in Traditional Medicine
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    • v.2 no.1
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    • pp.41-46
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    • 2002
  • In our study, the several cytokines were determined in phytohaemagglutinin (PHA)-stimulated peripheral blood mononuclear cells (PBMC) of Adamantiades-Behcets patients. Adamantiades-Behcets disease (ABD) is a systemic inflammatory disorder and might involve immune dysfunction. High levels of $TNF-\alpha,\;IL-1\beta$ and $IFN-{\gamma}$ indicate the activation of inflammatory reactions and immune system in ABD. Gami-Phedoc-San (GPS) is an Oriental herbal medication, which has been used in Korea for the treatment of ABD. GPS (1 mg/ ml) significantly inhibited the secretion of proinflammatory cytokines, $TNF-\alpha\;and\;IL-1\beta$, compared to absence of GPS (by $50.5{\pm}1.9%$ inhibition for $TNF-\alpha$ and $106.9{\pm}16.8%$ for $IL-1\beta$). GPS also inhibited the production of $IFN-\gamma$, immunoregulatory Th1 cytokine, by $78.4{\pm}2.8%$. The inhibitory effects of GPS on cytokine secretion showed dose-dependent manner, and the pre-treatment of 1 mg/ml GPS had better effects than immunosuppressive drug for treatment of ABD, cyclosporin A. Our results suggest that GPS treatment for ABD patients might have pharmacological activity of immune and inflammatory responses through the cytokine modulation.

Studies on the Effects of Water Extract from Mixture of Pine Needles, Sedum sarmentosum Bunge, Hijkiaorme, Buckwheat and Perlla Leaves on the Immune Function Activation (솔잎, 돌나물, 톳, 메밀, 깻잎 등 5가지 혼합 열수 추출물의 면역 활성 효과)

  • Ryu, Hye-Sook;Kim, Hyun-Sook
    • The Korean Journal of Food And Nutrition
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    • v.21 no.3
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    • pp.269-274
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    • 2008
  • Plants have long been used as a food source in Korea. In this study, we investigated the combined immunomodulative effects of a water extract mixture of(pine needles, Sedum sarmentosum Bunge, hijkiaorme, buckwheat and Peril a leaves) on Balb/c mice $7{\sim}8$ weeks old. The mice were fed a chow diet ad libitum and the plant extract was orally administered every other day for four weeks at two different concentrations(50 and 500 mg/kg BW). After preparing the single-cell suspension, splenocyte proliferation was determined by the MTT(3-[4,5-di-methylthiazol-2-y]-2,5-diphenyl terazolium bromide) assay. After 48hrs of incubation with the mitogens(ConA or LPS) splenocyte from the mice groups administered 50 and 500 mg/kg BW of the plant extract showed a significant increased in proliferation compared to the control group. A hemolytic plague forming cell assay was used to indicate antibody production against sheep red blood cells(SRBC). The number of antibody-secreting cells T-dependent antigen. The result of this study suggest that supplementation with this plant extract may regulate immune function by increasing splenocyte proliferation and the number of plaque forming cells.