scholarly journals The immunomodulatory effect of cathelicidin-B1 on chicken macrophages

2020 ◽  
Vol 51 (1) ◽  
Author(s):  
Lianci Peng ◽  
Maaike R. Scheenstra ◽  
Roel M. van Harten ◽  
Henk P. Haagsman ◽  
Edwin J. A. Veldhuizen
Keyword(s):  
Gene Expression ◽  
Immune Response ◽  
Inflammatory Cytokines ◽  
Culture Conditions ◽  
Titration Calorimetry ◽  
Macrophage Response ◽  
Microbial Infections ◽  
Chicken Macrophage ◽  
Inflammatory Profile ◽  
Pro Inflammatory Cytokines

Abstract Cathelicidins (CATHs) play an important role in the innate immune response against microbial infections. Among the four chicken cathelicidins, CATH-B1 is studied the least. In this study, the effect of CATH-B1 on the macrophage response towards avian pathogenic E. coli (APEC) and bacterial ligands was investigated. Our results show that APEC induced CATH-B1 gene expression in both a chicken macrophage cell line (HD11 cells) and primary macrophages, while expression of the other three CATHs was virtually unaffected. While the antimicrobial activity of CATH-B1 is very low under cell culture conditions, it enhanced bacterial phagocytosis by macrophages. Interestingly, CATH-B1 downregulated APEC-induced gene expression of pro-inflammatory cytokines (IFN-β, IL-1β, IL-6 and IL-8) in primary macrophages. In addition, CATH-B1 pre-incubated macrophages showed a significantly higher gene expression of IL-10 after APEC challenge, indicating an overall anti-inflammatory profile for CATH-B1. Using isothermal titration calorimetry (ITC), CATH-B1 was shown to bind LPS. This suggests that CATH-B1 reduces toll like receptor (TLR) 4 dependent activation by APEC which may partly explain the decreased production of pro-inflammatory cytokines by macrophages. On the contrary, direct binding of CATH-B1 to ODN-2006 enhanced the TLR21 dependent activation of macrophages as measured by nitric oxide production. In conclusion, our results show for the first time that CATH-B1 has several immunomodulatory activities and thereby could be an important factor in the chicken immune response.

scholarly journals Biotribological Tests of Osteochondral Grafts after Treatment with Pro-Inflammatory Cytokines

Cartilage ◽  
2021 ◽  
pp. 194760352199490
Author(s):  
Christoph Bauer ◽  
Hakan Göçerler ◽  
Eugenia Niculescu-Morzsa ◽  
Vivek Jeyakumar ◽  
Christoph Stotter ◽  
...  
Keyword(s):  
Gene Expression ◽  
Inflammatory Cytokines ◽  
Metabolic Activity ◽  
Wear Debris ◽  
Cartilage Tissue ◽  
Test Fluid ◽  
Osteochondral Grafts ◽  
Extracellular Matrix Components ◽  
Proteoglycan Content ◽  
Pro Inflammatory Cytokines

ObjectiveDuring osteoarthritis progression, cartilage degrades in a manner that influences its biomechanical and biotribological properties, while chondrocytes reduce the synthesis of extracellular matrix components and become apoptotic. This study investigates the effects of inflammation on cartilage under biomechanical stress using biotribological tests.MethodsBovine osteochondral grafts from five animals were punched out from the medial condyle and treated with or without pro-inflammatory cytokines (interleukin-1β [IL-1β], tumor necrosis factor-α [TNF-α], IL-6) for 2 weeks. After incubation, biotribological tests were performed for 2 hours (alternating 10 minutes test and pause respectively at 39°C, 180 N, 1 Hz, and 2 mm stroke). Before and after testing, the cartilage surface was imaged with a 3-dimensional microscope. During testing, the coefficient of friction (COF) was measured, while gene expression analysis and investigation of metabolic activity of chondrocytes were carried out after testing. Histological sections of the tissue and wear debris from the test fluid were also analyzed.ResultsAfter biotribological tests, surface cracks were found in both treated and untreated osteochondral grafts. In treated grafts, the COF increased, and the proteoglycan content in the cartilage tissue decreased, leading to structural changes. Chondrocytes from treated grafts showed increased expression of genes encoding for degradative enzymes, while cartilage-specific gene expression and metabolic activity exhibited no significant differences between treated and untreated groups. No measurable difference in the wear debris in the test fluid was found.ConclusionsTreatment of osteochondral grafts with cytokines results in a significantly increased COF, while also leading to significant changes in cartilage proteoglycan content and cartilage matrix compression during biotribological tests.

scholarly journals Serum Levels of Pro-inflammatory Cytokines in relationship to outcomes in Children with P. falciparum malaria, in Nnewi-South east Nigeria

1970 ◽  
Vol 42 (2) ◽  
pp. 142-146
Author(s):  
EC Okocha ◽  
NC Ibeh ◽  
EO Ukaejiofor ◽  
JC Ebenebe ◽  
JC Aneke ◽  
...  
Keyword(s):  
Immune Response ◽  
Platelet Count ◽  
Falciparum Malaria ◽  
Inflammatory Cytokines ◽  
Parasite Density ◽  
The Body ◽  
World Health ◽  
Inadequate Response ◽  
Monocyte Count ◽  
Pro Inflammatory Cytokines

Background and Objective: In P. falciparum malaria (PFM) infestation there are marked changes in cytokine production as the body mounts an immune response to it. Hence we set out to study these changes.Methods: A total of 158 cases of PFM among children attending the paediatric unit of our hospital and 56 healthy controls were studied. Children with febrile illness were screened for malaria using 10% Giemsa stained blood smear. Patients with positive smears were recruited; co-infected patients – those infected by another organism in addition to plasmodium specie.- were excluded. Whole blood was collected, some into plain tubes for serum cytokine testing and some into EDTA bottles for complete blood count and parasite density (PD) determination. Controls with asymptomatic parasitaemia were excluded.Results: Using the World Health Organization criteria for defining severe malaria; we identified 15 cases of severe and 143 cases of uncomplicated PFM. Significantly elevated levels of interleukin-1 (IL-1), interleukin 6 (IL-6) and tumour necrosis factor alpha (TNF-α) were seen in the uncomplicated and severe forms of PFM. It was observed that the elevated cytokine values correlated with PD (in uncomplicated PFM but not in the severe forms). The difference between PD/absolute monocyte count (AMC) ratio was not significant (p=0.13); while PD/platelet count (PC) and PC/ AMC ratios were significant (p=0.01, and 0.03 respectively) when compared between uncomplicated and severe disease.Conclusion: Our data seems to suggest that subjects with an adequate immune response to the parasite density, in terms of pro-inflammatory cytokine levels, presented with uncomplicated disease; while those who have an inadequate response presented with severe disease. The ratios of (PD/PC) and (PC/AMC), in the positive and negative directions respectively, may be predictors of increased disease severity. These observations may have implications for predicting disease outcome and PFM therapy.Key Words: plasmodium falciparum malaria, pro-inflammatory cytokines, Parasite density/Platelet count ratio, Platelet count/Absolute monocyte

scholarly journals Dectin-1-Mediated Production of Pro-Inflammatory Cytokines Induced by Yeast β-Glucans in Bovine Monocytes

2021 ◽  
Vol 12 ◽  
Author(s):  
Ana R. V. Pedro ◽  
Tânia Lima ◽  
Ricardo Fróis-Martins ◽  
Bárbara Leal ◽  
Isabel C. Ramos ◽  
...  
Keyword(s):  
Gene Expression ◽  
Cell Surface ◽  
Inflammatory Cytokines ◽  
Surface Expression ◽  
Cell Surface Receptor ◽  
Dependent Manner ◽  
Feed Supplements ◽  
Surface Receptor ◽  
Dose Dependent ◽  
Pro Inflammatory Cytokines

Yeast-derived products containing β-glucans have long been used as feed supplements in domesticated animals in an attempt to increase immunity. β-glucans are mainly recognized by the cell surface receptor CLEC7A, also designated Dectin-1. Although the immune mechanisms elicited through Dectin-1 activation have been studied in detail in mice and humans, they are poorly understood in other species. Here, we evaluated the response of bovine monocytes to soluble and particulate purified β-glucans, and also to Zymosan. Our results show that particulate, but not soluble β-glucans, can upregulate the surface expression of costimulatory molecules CD80 and CD86 on bovine monocytes. In addition, stimulated cells increased production of IL-8 and of TNF, IL1B, and IL6 mRNA expression, in a dose-dependent manner, which correlated positively with CLEC7A gene expression. Production of IL-8 and TNF expression decreased significantly after CLEC7A knockdown using two different pairs of siRNAs. Overall, we demonstrated here that bovine monocytes respond to particulate β-glucans, through Dectin-1, by increasing the expression of pro-inflammatory cytokines. Our data support further studies in cattle on the induction of trained immunity using dietary β-glucans.

TNF-alpha stimulates activation of pro-MMP2 in human skin through NF-(kappa)B mediated induction of MT1-MMP

2001 ◽  
Vol 114 (1) ◽  
pp. 131-139 ◽  
Author(s):  
Y.P. Han ◽  
T.L. Tuan ◽  
H. Wu ◽  
M. Hughes ◽  
W.L. Garner
Keyword(s):  
Gene Expression ◽  
Wound Healing ◽  
Human Skin ◽  
Inflammatory Cytokines ◽  
Intracellular Signaling ◽  
Chronic Wounds ◽  
Dermal Fibroblasts ◽  
Tnf Alpha ◽  
Nf Kappa B ◽  
Pro Inflammatory Cytokines

Tumor necrosis factor-alpha (TNF-(alpha)) is an important mediator during the inflammatory phase of wound healing. Excessive amounts of pro-inflammatory cytokines such as TNF-(alpha) are associated with inflammatory diseases including chronic wounds. Matrix metalloproteinases (MMPs) are involved in matrix re-modeling during wound healing, angiogenesis and tumor metastasis. As with pro-inflammatory cytokines, high levels of MMPs have been found in inflammatory states such as chronic wounds. In this report we relate these two phenomena. TNF-(alpha) stimulates secretion of active MMP-2, a type IV collagenase, in organ-cultured full-thickness human skin. This suggests a mechanism whereby excess inflammation affects normal wound healing. To investigate this observation at the cellular and molecular levels, we examined TNF-(alpha) mediated activation of pro-MMP-2, induction of MT1-MMP, and the intracellular signaling pathways that regulate the proteinase in isolated human dermal fibroblasts. We found that TNF-(alpha) substantially promoted activation of pro-MMP-2 in dermal fibroblasts embedded in type-I collagen. In marked contrast, collagen or TNF-(alpha) individually had little influence on the fibroblast-mediated pro-MMP-2 activation. One well-characterized mechanism for pro-MMP-2 activation is through a membrane type matrix metalloproteinase, such as MT1-MMP. We report that TNF-(alpha) significantly induced MT1-MMP at the mRNA and protein levels when the dermal fibroblasts were grown in collagen. Although the intracellular signaling pathway regulating mt1-mmp gene expression is still obscure, both TNF-(alpha) and collagen activate the NF-(kappa)B pathway. In this report we provide three sets of evidence to support a hypothesis that activation of NF-(kappa)B is essential to induce MT1-MMP expression in fibroblasts after TNF-(alpha) exposure. First, SN50, a peptide inhibitor for NF-(kappa)B nuclear translocation, simultaneously blocked the TNF-(alpha) and collagen mediated MT1-MMP induction and pro-MMP-2 activation. Secondly, TNF-(alpha) induced I(kappa)B to breakdown in fibroblasts within the collagen lattice, a critical step leading to NF-(kappa)B activation. Lastly, a consensus binding site for p65 NF-(kappa)B (TGGAGCTTCC) was found in the 5′-flanking region of human mt1-mmp gene. Based on these results and previous reports, we propose a model to explain TNF-(alpha) activation of MMP-2 in human skin. Activation of NF(kappa)B signaling in fibroblasts embedded in collagen induces mt1-mmp gene expression, which subsequently activates the pro-MMP-2. The findings provide a specific mechanism whereby TNF-(alpha) may affect matrix remodeling during wound healing and other physiological and pathological processes.

scholarly journals Extracellular vesicles from human cardiovascular progenitors trigger a reparative immune response in infarcted hearts

2020 ◽  
Author(s):  
Bruna Lima Correa ◽  
Nadia El Harane ◽  
Ingrid Gomez ◽  
Hocine Rachid Hocine ◽  
José Vilar ◽  
...  
Keyword(s):  
Immune Response ◽  
Extracellular Vesicles ◽  
Inflammatory Cytokines ◽  
Nk Cell ◽  
Inflammatory Monocytes ◽  
Ifn Γ ◽  
Anti Inflammatory ◽  
Pro Inflammatory Cytokines

Abstract Aims The cardioprotective effects of human induced pluripotent stem cell-derived cardiovascular progenitor cells (CPC) are largely mediated by the paracrine release of extracellular vesicles (EV). We aimed to assess the immunological behaviour of EV-CPC, which is a prerequisite for their clinical translation. Methods and results Flow cytometry demonstrated that EV-CPC expressed very low levels of immune relevant molecules including HLA Class I, CD80, CD274 (PD-L1), and CD275 (ICOS-L); and moderate levels of ligands of the natural killer (NK) cell activating receptor, NKG2D. In mixed lymphocyte reactions, EV-CPC neither induced nor modulated adaptive allogeneic T cell immune responses. They also failed to induce NK cell degranulation, even at high concentrations. These in vitro effects were confirmed in vivo as repeated injections of EV-CPC did not stimulate production of immunoglobulins or affect the interferon (IFN)-γ responses from primed splenocytes. In a mouse model of chronic heart failure, intra-myocardial injections of EV-CPC, 3 weeks after myocardial infarction, decreased both the number of cardiac pro-inflammatory Ly6Chigh monocytes and circulating levels of pro-inflammatory cytokines (IL-1α, TNF-α, and IFN-γ). In a model of acute infarction, direct cardiac injection of EV-CPC 2 days after infarction reduced pro-inflammatory macrophages, Ly6Chigh monocytes, and neutrophils in heart tissue as compared to controls. EV-CPC also reduced levels of pro-inflammatory cytokines IL-1α, IL-2, and IL-6, and increased levels of the anti-inflammatory cytokine IL-10. These effects on human macrophages and monocytes were reproduced in vitro; EV-CPC reduced the number of pro-inflammatory monocytes and M1 macrophages, while increasing the number of anti-inflammatory M2 macrophages. Conclusions EV-CPC do not trigger an immune response either in in vitro human allogeneic models or in immunocompetent animal models. The capacity for orienting the response of monocyte/macrophages towards resolution of inflammation strengthens the clinical attractiveness of EV-CPC as an acellular therapy for cardiac repair.

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