β-glucan from Aureobasidium pullulans augments the anti-tumor immune responses through activated tumor-associated dendritic cells

2021 ◽  
Vol 101 ◽  
pp. 108265
Author(s):  
Yifang Shui ◽  
Xin Hu ◽  
Hiroshi Hirano ◽  
Kisato Kusano ◽  
Hirotake Tsukamoto ◽  
...  
Keyword(s):  
Dendritic Cells ◽  
Immune Responses ◽  
Aureobasidium Pullulans

scholarly journals Innate cell profiles during the acute and convalescent phase of SARS-CoV-2 infection in children

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Melanie R. Neeland ◽  
Samantha Bannister ◽  
Vanessa Clifford ◽  
Kate Dohle ◽  
Kim Mulholland ◽  
...  
Keyword(s):  
Immune Response ◽  
Dendritic Cells ◽  
Immune Responses ◽  
Acute Phase ◽  
Innate Immune ◽  
Low Density ◽  
Innate Immune Responses ◽  
Immunological Mechanisms ◽  
Activated Neutrophils ◽  
Classical Monocytes

AbstractChildren have mild severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) confirmed disease (COVID-19) compared to adults and the immunological mechanisms underlying this difference remain unclear. Here, we report acute and convalescent innate immune responses in 48 children and 70 adults infected with, or exposed to, SARS-CoV-2. We find clinically mild SARS-CoV-2 infection in children is characterised by reduced circulating subsets of monocytes (classical, intermediate, non-classical), dendritic cells and natural killer cells during the acute phase. In contrast, SARS-CoV-2-infected adults show reduced proportions of non-classical monocytes only. We also observe increased proportions of CD63+ activated neutrophils during the acute phase to SARS-CoV-2 in infected children. Children and adults exposed to SARS-CoV-2 but negative on PCR testing display increased proportions of low-density neutrophils that we observe up to 7 weeks post exposure. This study characterises the innate immune response during SARS-CoV-2 infection and household exposure in children.

scholarly journals A Missing Link: Engagements of Dendritic Cells in the Pathogenesis of SARS-CoV-2 Infections

2021 ◽  
Vol 22 (3) ◽  
pp. 1118
Author(s):  
Abdulaziz Alamri ◽  
Derek Fisk ◽  
Deepak Upreti ◽  
Sam K. P. Kung
Keyword(s):  
Dendritic Cells ◽  
Severe Acute Respiratory Syndrome ◽  
Immune Responses ◽  
Immune Cell ◽  
Inflammatory Responses ◽  
Viral Disease ◽  
Cell Recruitment ◽  
Cross Presentation ◽  
Cell Immunity ◽  
Immune Cell Recruitment

Dendritic cells (DC) connect the innate and adaptive arms of the immune system and carry out numerous roles that are significant in the context of viral disease. Their functions include the control of inflammatory responses, the promotion of tolerance, cross-presentation, immune cell recruitment and the production of antiviral cytokines. Based primarily on the available literature that characterizes the behaviour of many DC subsets during Severe acute respiratory syndrome (SARS) and coronavirus disease 2019 (COVID-19), we speculated possible mechanisms through which DC could contribute to COVID-19 immune responses, such as dissemination of Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) to lymph nodes, mounting dysfunctional inteferon responses and T cell immunity in patients. We highlighted gaps of knowledge in our understanding of DC in COVID-19 pathogenesis and discussed current pre-clinical development of therapies for COVID-19.

scholarly journals Rapamycin Alternatively Modifies Mitochondrial Dynamics in Dendritic Cells to Reduce Kidney Ischemic Reperfusion Injury

2021 ◽  
Vol 22 (10) ◽  
pp. 5386
Author(s):  
Maria Namwanje ◽  
Bijay Bisunke ◽  
Thomas V. Rousselle ◽  
Gene G. Lamanilao ◽  
Venkatadri S. Sunder ◽  
...  
Keyword(s):  
Dendritic Cells ◽  
Immune Responses ◽  
Therapeutic Potential ◽  
Ex Vivo ◽  
Mitochondrial Dynamics ◽  
Graft Loss ◽  
Kidney Injury ◽  
Adaptive Immune ◽  
Consumption Rates ◽  
Regulatory Phenotype

Dendritic cells (DCs) are unique immune cells that can link innate and adaptive immune responses and Immunometabolism greatly impacts their phenotype. Rapamycin is a macrolide compound that has immunosuppressant functions and is used to prevent graft loss in kidney transplantation. The current study evaluated the therapeutic potential of ex-vivo rapamycin treated DCs to protect kidneys in a mouse model of acute kidney injury (AKI). For the rapamycin single (S) treatment (Rapa-S-DC), Veh-DCs were treated with rapamycin (10 ng/mL) for 1 h before LPS. In contrast, rapamycin multiple (M) treatment (Rapa-M-DC) were exposed to 3 treatments over 7 days. Only multiple ex-vivo rapamycin treatments of DCs induced a persistent reprogramming of mitochondrial metabolism. These DCs had 18-fold more mitochondria, had almost 4-fold higher oxygen consumption rates, and produced more ATP compared to Veh-DCs (Veh treated control DCs). Pathway analysis showed IL10 signaling as a major contributing pathway to the altered immunophenotype after Rapamycin treatment compared to vehicle with significantly lower cytokines Tnfa, Il1b, and Il6, while regulators of mitochondrial content Pgc1a, Tfam, and Ho1 remained elevated. Critically, adoptive transfer of rapamycin-treated DCs to WT recipients 24 h before bilateral kidney ischemia significantly protected the kidneys from injury with a significant 3-fold improvement in kidney function. Last, the infusion of DCs containing higher mitochondria numbers (treated ex-vivo with healthy isolated mitochondria (10 µg/mL) one day before) also partially protected the kidneys from IRI. These studies demonstrate that pre-emptive infusion of ex-vivo reprogrammed DCs that have higher mitochondria content has therapeutic capacity to induce an anti-inflammatory regulatory phenotype to protect kidneys from injury.

scholarly journals Tolerogenic Splenic IDO+Dendritic Cells from the Mice Treated with Induced-Treg Cells Suppress Collagen-Induced Arthritis

2014 ◽  
Vol 2014 ◽  
pp. 1-12 ◽  
Author(s):  
Jie Yang ◽  
Yiming Yang ◽  
Huahua Fan ◽  
Hejian Zou
Keyword(s):  
Dendritic Cells ◽  
Immune Responses ◽  
Foxp3 Expression ◽  
Treated Group ◽  
Treg Cells ◽  
Therapeutic Effects ◽  
Dependent Manner ◽  
Collagen Induced Arthritis

TGF-β-induced regulatory T cells (iTregs) retain Foxp3 expression and immune-suppressive activity in collagen-induced arthritis (CIA). However, the mechanisms whereby transferred iTregs suppress immune responses, particularly the interplay between iTregs and dendritic cells (DCs)in vivo, remain incompletely understood. In this study, we found that after treatment with iTregs, splenic CD11c+DCs, termed “DCiTreg,” expressed tolerogenic phenotypes, secreted high levels of IL-10, TGF-β, and IDO, and showed potent immunosuppressive activityin vitro. After reinfusion with DCiTreg, marked antiarthritic activity improved clinical scores and histological end-points were observed. The serological levels of inflammatory cytokines and anti-CII antibodies were low and TGF-βproduction was high in the DCiTreg-treated group. DCiTregalso induced new iTregsin vivo. Moreover, the inhibitory activity of DCiTregon CIA was lost following pretreatment with the inhibitor of indoleamine 2,3-dioxygenase (IDO). Collectively, these findings suggest that transferred iTregs could induce tolerogenic characteristics in splenic DCs and these cells could effectively dampen CIA in an IDO-dependent manner. Thus, the potential therapeutic effects of iTregs in CIA are likely maintained through the generation of tolerogenic DCsin vivo.

scholarly journals A genetically engineered adenovirus vector targeted to CD40 mediates transduction of canine dendritic cells and promotes antigen-specific immune responses in vivo

Vaccine ◽  
2009 ◽  
Vol 27 (50) ◽  
pp. 7116-7124 ◽  
Author(s):  
Erin E. Thacker ◽  
Masaharu Nakayama ◽  
Bruce F. Smith ◽  
R. Curtis Bird ◽  
Zhanat Muminova ◽  
...  
Keyword(s):  
Dendritic Cells ◽  
Immune Responses ◽  
Adenovirus Vector ◽  
Genetically Engineered

scholarly journals Germinal Center Initiation, Variable Gene Region Hypermutation, and Mutant B Cell Selection without Detectable Immune Complexes on Follicular Dendritic Cells

2000 ◽  
Vol 192 (7) ◽  
pp. 931-942 ◽  
Author(s):  
Lynn G. Hannum ◽  
Ann M. Haberman ◽  
Shannon M. Anderson ◽  
Mark J. Shlomchik
Keyword(s):  
Dendritic Cells ◽  
Immune Responses ◽  
B Cell ◽  
Immune Complexes ◽  
Germinal Center ◽  
Serum Antibody ◽  
Cell Formation ◽  
Immunoglobulin M ◽  
Follicular Dendritic Cells ◽  
Follicular Dendritic

Serum antibody (Ab) can play several roles during B cell immune responses. Among these is to promote the deposition of immune complexes (ICs) on follicular dendritic cells (FDCs). ICs on FDCs are generally thought to be critical for normal germinal center (GC) formation and the development and selection of memory B cells. However, it has been very difficult to test these ideas. To determine directly whether FDC-bound complexes do indeed function in these roles, we have developed a transgenic (Tg) mouse in which all B lymphocytes produce only the membrane-bound form of immunoglobulin M. Immune Tg mice have 10,000-fold less specific Ab than wild-type mice and lack detectable ICs on FDCs. Nonetheless, primary immune responses and the GC reaction in these mice are robust, suggesting that ICs on FDCs do not play critical roles in immune response initiation and GC formation. Moreover, as indicated by the presence and pattern of somatic mutations, memory cell formation and selection appear normal in these IC-deficient GCs.

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