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Published in Ashfaq A Marghoob, Ralph Braun, Natalia Jaimes, Atlas of Dermoscopy, 2023
Natalia Jaimes, Michael A. Marchetti
Mucous membranes are epithelial surfaces with mucus-secreting cells that form the lining of body cavities; for example, the mucosa of the mouth lines the oral cavity, including the gingivae, palate, lips, buccal surfaces, and floor of the mouth.1 Mucous membranes are generally nonkeratinized stratified squamous epitheliums, although different sites demonstrate varying degrees of keratinization. Examples of mucosal surfaces include the conjunctivae, oral mucosa, nasal mucosa, and anogenital mucosa.
Introduction to Infection, Resistance, and Immunity
Published in Julius P. Kreier, Infection, Resistance, and Immunity, 2022
In this type of immunity, just as with martial arts, all parts of the body are used in defense and as weapons against the foe, here, disease-causing organisms. The surfaces that come into intimate contact with the environment both present a physical barrier to environmental pathogens and are endowed with antimicrobial activities. The skin of the frog and the silkworm contains short hydrophobic peptides, called cecropins, that lyse fragile protozoan parasites. Mammal skin is dotted with hair follicles and associated sebaceous glands that secrete antimicrobial lactic and fatty acids. Antimicrobial agents in sweat, tears, and saliva limit growth of microorganisms in these secretions. Pathogens that are inhaled are often trapped in mucin at mucosal surfaces, expelled back into the mouth, swallowed, and exposed to damaging treatment with acid, bile, and enzymes of the digestive tract. Sneezing, coughing, vomiting, diarrhea, and urination all play a role in removal of infectious agents from the body. Products of adaptive immune responses also participate in the maintenance of barrier immunity, e.g., pathogen-reactive antibodies of the IgA class, are secreted at mucosal surfaces and help to reduce infection by binding to structures on microbes that facili ta te invasion.
Urticaria and Angioedema
Published in Pudupakkam K Vedanthan, Harold S Nelson, Shripad N Agashe, PA Mahesh, Rohit Katial, Textbook of Allergy for the Clinician, 2021
Jenny M Stitt, Stephen C Dreskin
Symptoms of HAE include episodes of swelling that can be quite painful and can affect any part of the body (Dreskin 2012, Hiragun et al. 2013, Longhurst and Cicardi 2012, Sardana and Craig 2011). Angioedema episodes may be heralded by a faint erythematous rash (not urticaria) at locations unrelated to ensuing edema. Common areas of swelling include the face, tongue, hands, feet, genitals and abdomen. Patients also experience swelling of mucosal surfaces. Angioedema of the larynx or uvula and gastrointestinal tract have been observed. Gastrointestinal manifestations can lead to imaging and other diagnostic searches for an elusive cause of symptoms. Prior to the availability of effective treatment for HAE, there was a significant risk of death due to asphyxiation from laryngeal edema. This risk has been reduced by modern treatments, but still exists.
Current evidence of biofilms in chronic rhinosinusitis- a microbiological perspective
Published in Expert Review of Clinical Immunology, 2023
Arne Koefoed, Brett Wagner Mackenzie, Richard Douglas, Kristi Biswas
Currently, available methodologies for identifying biofilms on mucosal surfaces are not sufficiently well-developed to be used in a clinical setting. As technologies improve, they should better inform our clinical practice. There will most likely be a move away from the current laborious electron microscopy or in vitro culture methods of uncertain value toward molecular approaches. The latest molecular techniques using gene-targeted technologies have the potential for a more accurate, sensitive, faster and cheaper way forward, but these remain in their infancy. A major roadblock to progress with this approach is the lack of a universal biofilm gene target. Unlike next-generation sequencing technologies that rely on the amplification of the 16S rRNA gene, which is found in all bacteria and enables the description of bacterial community (microbiota) composition in samples, there is no equivalent target for biofilm-related genes. Each bacterial species has a unique set of genes associated with biofilm production, making it difficult to apply a general biofilm screening approach to clinical samples.
The role of bactericidal and opsonic activity in immunity against Bordetella pertussis
Published in Expert Review of Vaccines, 2022
Pascal Blanc, Yuanqing Liu, Nathalie Reveneau, Breeze Cavell, Andrew Gorringe, Geneviève Renauld-Mongénie
A key activity to determine the relevance of SBA and OPA in immunity elicited by either B. pertussis infection or vaccination is the development of relevant and reproducible assays. Both SBA and OPA assays require a source of complement. Ideally, this would be from human serum or plasma due to the potential for species-specific complement interactions and evasion mechanisms which have yet to be characterized. Preexisting anti-B. pertussis antibodies in most human sera make this a problem which can be solved by removing IgG and IgM as previously described [47,62,97]. Standard methods should also use relevant isolates and standard sera so that results can be compared between studies. In addition, methods are required to analyze bactericidal and opsonic activity on the mucosal surface.
Heat acclimation does not negatively affect salivary immunoglobulin-A and self-reported illness symptoms and wellness in recreational athletes
Published in Temperature, 2022
Puck Alkemade, Nicola Gerrett, Hein A. M. Daanen, Thijs M. H. Eijsvogels, Thomas W. J. Janssen, Lauren C. Keaney
Measurement of salivary biomarkers has been used as a tool to monitor URTS risk in athletes [2,8–10]. Mucosal surfaces, for example in the oral cavity, are protected by mucosal secretions that act as “the first line of defense” against infectious pathogens. Defense factors in saliva include alpha-amylase, lactoferrin, lysozyme, and immunoglobulins, with immunoglobulin-A being the most abundant secretory antibody [9,11]. Salivary immunoglobulin-A (s-IgA) has been studied extensively and research suggests that s-IgA availability diminishes with intensified training periods, resulting in elevated URTS risk [12,13]. Indeed, a recent systematic review identified both increased training intensity and reduced s-IgA as risk factors for the development of clinically diagnosed upper respiratory tract infection [10]. It should be noted, however, that URTS do not necessarily have an infective origin, but can also result from factors such as allergies or asthma [14], clouding the relationship between s-IgA and URTS. Some studies showed that high URTS incidences around intense training periods were preceded by relatively low s-IgA concentrations [8,15,16], although this is not a consistent finding [17–19].