Search results for "MUCOSA"
showing 10 items of 1066 documents
Effects of adjuvants of the cholera toxin family on CD4 + T cell responses in a murine model of intrarectal immunization with rotavirus-like particles
2011
Mucosal immunization is an important goal of vaccine development to protect against pathogens that use mucosa as portals of entry. However, the use of non-replicating antigens requires the addition of adjuvants.Cholera-like enterotoxins, cholera toxin (CT) from Vibrio cholerae and the heat-labile enterotoxin (LT) from toxinogenic strains of E. coli, as well as the mutant LR-192G and their B subunits (CTB and LTB) have been shown to increase immune responses against unrelated co-administered antigens by mucosal routes. However, their mechanism of action is very complex and not completely understood and differences exist between holotoxins and B subunits and within molecules, differences exis…
Candida albicans-epithelial interactions: dissecting the roles of active penetration, induced endocytosis and host factors on the infection process
2012
International audience; Candida albicans frequently causes superficial infections by invading and damaging epithelial cells, but may also cause systemic infections by penetrating through epithelial barriers. C. albicans is a remarkable pathogen because it can invade epithelial cells via two distinct mechanisms: induced endocytosis, analogous to facultative intracellular enteropathogenic bacteria, and active penetration, similar to plant pathogenic fungi. Here we investigated the contributions of the two invasion routes of C. albicans to epithelial invasion. Using selective cellular inhibition approaches and differential fluorescence microscopy, we demonstrate that induced endocytosis contri…
Soft tissue integration of different abutment surfaces: An experimental study with histological analysis
2021
OBJECTIVE To evaluate whether abutment surface and surface bio-activation have an effect on soft tissue morphogenesis. MATERIALS AND METHODS 36 patients (36 implants) were included. Abutments were randomly divided into 4 groups (n = 9): Smooth Surface-MAChined (MAC), Ultrathin Threaded Microsurface (UTM), MAC Plasma of Argon activated (Plasma-MAC), and UTM Plasma of Argon activated (Plasma-UTM). After 2 months of healing, soft tissue samples were collected and prepared for histological analysis. The margin of the peri-implant mucosa (PM), the apical extension of the barrier epithelium (aJE), and the apical location of the abutment (AM) were identified. Significances of differences among gro…
Molecular mechanisms of primary and secondary mucosal immunity using avian infectious bronchitis virus as a model system
2007
Although mucosal immune responses are critical for protection of hosts from clinical illness and even mortality caused by mucosal pathogens, the molecular mechanism of mucosal immunity, which is independent of systemic immunity, remains elusive. To explore the mechanistic basis of mucosal protective immunity, gene transcriptional profiling in mucosal tissues was evaluated after the primary and secondary immunization of animals with an attenuated avian infectious bronchitis virus (IBV), a prototype of Coronavirus and a well-characterized mucosal pathogen. Results showed that a number of innate immune factors including toll-like receptors (TLRs), retinoic-acid-inducible gene-1 (RIG-1), type I…
Smad7 controls resistance of colitogenic T cells to regulatory T cell-mediated suppression.
2008
Background & Aims Foxp3-expressing regulatory T cells (Tregs) play a key role in the maintenance of the gut immune homeostasis, and an intact transforming growth factor (TGF)-β signaling is required for their function. In inflammatory bowel disease (IBD), the TGF-β signaling is impaired because of high expression of the inhibitory molecule Smad7. Although no intrinsic defects in Tregs function have been shown in IBD, it is still unknown whether colitogenic T cells are susceptible to Treg-mediated suppression. In this study, we have investigated whether IBD mucosal CD4+ T cells are resistant to Tregs and whether Smad7 is involved in this process. Methods IBD lamina propria mononuclear cells …
Refractory coeliac disease: one step closer to the origin of aberrant lymphocytes.
2012
Aberrant intraepithelial lymphocytes (IELs) are the key feature of refractory coeliac disease type II (RCDII), but the cellular origin of these aberrant IELs remains unclear. In a recent paper Schmitz et al 1 further explored previously characterised aberrant IEL cell lines from four patients with RCDII by using a broad spectrum of cell specific markers, RNA array and immunological techniques, to compare these cell lines to IELs from the fetal intestine, the intestine of children and adults and the thymus. IELs are a heterogeneous population of lymphocytes with innate and adaptive features that inhabit the small and large intestine. IELs are important for the maintenance of tolerance to com…
Candida-associated denture stomatitis
2010
Candida albicans is a dimorphic yeast strongly gram positive able to live as normal commensal organism in the oral cavity of healthy people. It is the yeast more frequently isolated in the oral cavity. Under local and systemic factors related to the host conditions, it becomes virulent and responsible of oral diseases known as oral candidiasis. It has been shown that the presence of denture is a predisposing factor to the onset of pathologies related to C. albicans. Clinical studies have shown that C. albicans is not only able to adhere to the mucous surfaces, but also to stick to the acrylic resins of the dental prostheses. Both the plaque accumulated on the denture and the poor oral hygie…
Is Khat (Catha edulis) chewing a risk factor for periodontal diseases? : a systematic review
2017
Background Khat (Catha edulis) chewing is a highly prevalent habit in the Arabian Peninsula and East Africa, and has recently spread to Western countries. The association between khat chewing and oral mucosal lesions is well documented in the literature. However, there is no concrete evidence on the association between khat chewing and periodontal disease. The purpose of this systematic review was to analyze the influence of khat chewing on periodontal health. Material and methods A literature search of PubMed, Scopus and Web of Sciences databases was carried out to identify relevant articles published from 1990 to May 2017. The inclusion criteria were all clinical studies that assessed the…
Medication related to pigmentation of oral mucosa.
2021
The diagnosis of oral melanotic lesions is, more often than not, challenging in the clinical practice due to the fact that there are several reasons which may cause an increase in pigmentation on localized or generalized areas. Among these, medication stands out. In this work, we have carried out a review in the reference pharma database: Micromedex® followed by a review of the scientific published literature to analyse coincidences and possible discrepancies. Our findings show that there are several prescription drugs that can cause pigmented lesions in the oral mucosa. This must be known by clinicians in order to properly diagnose pigmented lesions. We have identified a set of 21 medicame…
A multipronged approach to unveil the emerging role of Hsp60 in chronic obstructive pulmonary disease
2011
Inflammation is a major component of chronic obstructive pulmonary disease (COPD) and its cause and mechanisms are still incompletely understood. For example, the role of heat shock proteins (Hsps), many of which are molecular chaperones, has not been explored in detail in COPD, despite the fact that these molecules are known to participate in inflammation in other diseases. It has been shown that extracellular Hsps can signal certain types of T cells, macrophages, dendritic cells, and neutrophils and, thereby, elicit inflammation and immunity. However, these phenomena have not been investigated in COPD despite: a) the increasing awareness of Hsp participation in inflammation and immunity; …