Search results for " immune system"

The echinoderm innate humoral immune response

2015

Abstract: Multicellular organisms have an immune system, which is essential for the survival of living beings. Interest in the immune system has been expanded since common characteristics of innate immunity between Drosophila melanogaster (Meigen, 1830) and mammals were discovered in the 1980. Since then, immunology has mainly focused on the adaptive immune system that seems to be restricted to vertebrates. Unlike the innate immunity, the adaptive one is acquired after exposure to a specific antigen (Ag) and includes: antigen-presenting cells such as macrophages, proliferation of B and T lymphocytes, Ag-specific antibody/cytokine production and immunological memory. Innate immunity is inste…

Crosstalk of the plasma contact system with bacteria.

2012

Activation of the plasma contact system triggers several cascade systems such as the kallikrein-kinin system, the intrinsic pathway of coagulation, the classical complement cascade and the fibrinolytic system. Recent studies have shown a critical role of the contact system for arterial and venous thrombus formation and thromboembolic disease. In contrast, the function of the contact system for host-defense reactions and its physiological functions have remained enigmatic. Experimental animal studies and clinical data have linked the contact system to bacterial infections with implications for sepsis disease. The present review summarizes the role of the contact system and its activation for…

Isolation of T Cells from the Gut

2014

The lymphocytes of epithelial and lamina proprial compartments of the intestine are phenotypically and functionally distinct and serve a wide range of functions in the intestinal mucosa like regulating intestinal homeostasis, maintaining epithelial barrier function as well as regulating adaptive and innate immune responses. To analyze the role of these cells in different disease states, it is necessary to isolate pure cell populations of the intraepithelial lymphocytes (IEL) and lamina propria lymphocytes (LPL) of the gut. In this protocol we describe a method to isolate T cells from IEL and LPL, which can be used for further investigations like comparative studies of mRNA expression, cell …

Cutaneous RANK-RANKL Signaling Upregulates CD8-Mediated Antiviral Immunity during Herpes simplex Virus Infection by Preventing Virus-Induced Langerha…

2015

Herpes simplex virus-type 1 (HSV-1) causes the majority of cutaneous viral infections. Viral infections are controlled by the immune system, and CD8(+) cytotoxic T-lymphocytes (CTLs) have been shown to be crucial during the clearance of HSV-1 infections. Although epidermal Langerhans cells (LCs) are the first dendritic cells (DCs) to come into contact with the virus, it has been shown that the processing of viral antigens and the differentiation of antiviral CTLs are mediated by migratory CD103+ dermal DCs and CD8 alpha(+) lymph node resident DCs. In vivo regulatory T-cells (Tregs) are implicated in the regulation of antiviral immunity and we have shown that signaling via the receptor activ…

Langerinneg conventional dendritic cells produce IL-23 to drive psoriatic plaque formation in mice.

2013

Psoriasis is an autoinflammatory skin disease of unknown etiology. Topical application of Aldara cream containing the Toll-like receptor (TLR)7 agonist Imiquimod (IMQ) onto patients induces flares of psoriasis. Likewise, in mice IMQ triggers pathological changes closely resembling psoriatic plaque formation. Key cytokines like IL-23 and type-I IFN (IFN-I), both being produced mainly by dendritic cells (DCs), have been implicated in psoriasis. Although plasmacytoid DCs (pDCs) are the main source of IFNα and thought to initiate disease, conventional DCs (cDCs) appear to maintain the psoriatic lesions. Any role of cDCs during lesion formation remains elusive. Here, we report that selective ac…

Langerhans cells are negative regulators of the anti-Leishmania response

2011

Langerhans cells suppress the immune response to low-dose Leishmania major infection in part by inducing regulatory T cells.

Routes in Innate Immunity Evolution: Galectins and Rhamnose-binding Lectins in Ascidians

2013

Immunological priming in the wood tiger moth (Parasemia plantaginis)

2014

Hyönteisiin lukeutuu monia merkittäviä tuholaisia, taudinvälittäjiä ja hyödyllisiä lajeja, minkä takia hyönteisten taudit, taudinaiheuttajat ja immuunipuolustus ovat ekologisesta, ekonomisesta ja lääketieteellisestä näkökulmasta tärkeitä tutkimuskohteita. Viimeaikaiset tutkimukset paljastavat hyönteisten ja muiden selkärangattomien immuunijärjestelmien pystyvän erikoistumaan ja luomaan pitkäkestoista immuniteettia. Jälkimmäinen ilmiö tunnetaan tieteellisissä artikkeleissa nimellä ”immunological priming”, jonka voisi kääntää suomeksi esimerkiksi ”immuunipohjustukseksi”. Immuunipohjustus on muistinkaltaista vastustuskykyä, joka auttaa elimistöä puolustautumaan tehokkaammin toistuvia tartuntoj…

Cigarette smoke increases BLT2 receptor functions in bronchial epithelial cells: in vitro and ex vivo evidence

2013

Summary Leukotriene B4 (LTB4) is a neutrophil chemotactic molecule with important involvement in the inflammatory responses of chronic obstructive pulmonary disease (COPD). Airway epithelium is emerging as a regulator of innate immune responses to a variety of insults including cigarette smoke, the major risk factor for COPD. In this study we have explored whether cigarette smoke extracts (CSE) or soluble mediators present in distal lung fluid samples (mini-bronchoalveolar lavages) from smokers alter the expression of the LTB4 receptor 2 (BLT2) and peroxisome proliferator-activated receptor-α (PPAR-α) in bronchial epithelial cells. We also evaluated the effects of CSE on the expression of i…

Hop-derived fraction rich in beta acids and prenylflavonoids regulates the inflammatory response in dendritic cells differently from quercetin: unvei…

2021

Dendritic cells (DCs) represent a heterogeneous family of immune cells that link innate and adaptive immunity and their activation is linked to metabolic changes that are essential to support their activity and function. Hence, targeting the metabolism of DCs represents an opportunity to modify the inflammatory and immune response. Among the natural matrices, Humulus lupulus (Hop) compounds have recently been shown to exhibit immunomodulatory and anti-inflammatory activity. This study aimed to evaluate the ability of specific Hop fractions to modulate DCs metabolism after stimulation with lipopolysaccharide (LPS) by an untargeted metabolomics approach and compare their effect with flavonol …