Immune responses mucosal surfaces

Jaganathan, K. S., and Vyas, S. P. (2006), Strong systemic and mucosal immune responses to surface-modified PLGA microspheres containing recombinant hepatitis B antigen administered intranasally, Vaccine, 24,4201-4211. 

GAl-derived proteins were detected in ES products from adult worms and host abomasal mucus, indicative of release from the microvillar surface. Following from this, protective immunity stimulated by immunization with these proteins may involve anamnestic and mucosal immune responses. This suggestion was supported in a later study (Karanu et al., 1997a), which provided evidence for a contribution from CD4+ lymphocytes to gut antigen-induced immunity. 

The respiratory mucosal surface is chronically exposed to a plethora of non-pathogenic environmental antigens, some of which are potential triggers for allergic disease. In order to protect against the immunopathological consequences of continuously responding to these ubiquitous stimuli, the local default immune response takes the form of non-inflammatory low-level T-helper 2 (Th2) immunity [1-4] and/or a form of T-cell-mediated... 

The induction of an immune response by various mucosal routes is an important approach for the control of mucosally acquired infections. The apparent linked nature of the mucosal immune system enables the delivery of an antigen to any mucosal surface to have the secondary effect of potentially inducing immunity at others. Induction of a combination of systemic and secretory immune responses can be determined by the nature of the antigen, the route of administration, and the delivery system utilized. For example, traditional parenteral vaccines primarily induce IgM and IgG responses, whereas mucosal vaccination can elicit both IgG and secretory IgA responses (Corthesy, 2007). 

Inflammatory influences. Inflammation (p. 1211), which usually accompanies infection and can also arise from allergic responses, is affected by many substances.2293-6 These include chemotactic factors that attract neutrophils and monocytes2220 2294 and the adhesion molecules that assist in the movement of lymphocytes. 229e/f Some epithelial tissues, such as the mucosal surfaces of the gastrointestinal tract, are maintained in a continuous very low level of inflammation. This reflects the balance between activation of the immune system and inhibition of the system by signals from microorganisms both pathogenic and commensal 229 h... 

An intriguing question concerns the immune response elicited by allergen extracts at the mucosal surface. Some studies, in animal models, provided interesting information the dendritic cells of oral mucosa act as efficient antigen-presenting cells and produce IL-12, which directs the immune response towards a Thl profile away from pro-IgE-Th2 profile [6-8],... 

Commensal bacteria, capable of colonizing mucosal surfaces, which are genetically engineered to express viral, bacterial, or eukaryotic antigens to produce an immune response... 

A wide variety of novel approaches for the development of mucosal immune responses by administration of antigens in different delivery systems have been investigated, in many cases, with considerable success. These approaches include (1) the coadministration of immunogens with adjuvants active at the mucosal surface, (2) the coupling of immunogens to carrier molecules that promote their uptake at the mucosal inductive site, and (3) the expression of antigens in live attenuated bacterial or viral vectors, which can promote the colonization of mucosal tissue and the incorporation of antigens into a variety of microparticulate and adhesive vehicles, which are taken up in mucosal inductive sites. 

Lymphocytes (T cells)—a group of white blood cells of crucial importance to the adaptive part of the organism s immune system. There are many kinds of lymphocytes (Th 0, Th c, Th 1, Th 2, Th 17). Cytokines produced by T cells probably play a major role in orchestrating allergic inflammation. TH 1 cells produce IFN-y and IL-2 but not IL-4 or IL-5 after activation. TH2 cells produce mainly IL-4, IL-13, and IL-5 but not IL-2 or IFN-y. TH2 cells characterize human allergic responses and are present at mucosal surfaces during the late but not immediate response to an allergen exposure. 

Conneely, 2001). LF has the ability to bind to the surface of several types of immune cells, which suggests that it can modulate immune functions. Both stimulatory and inhibitory effects of LF on lymphocyte proliferation have been described in the literature. LF has been reported to induce in vitro maturation of T- and B-lymphocytes, to modulate the activity of natural killer cells and to enhance the phagocytic activity of neutrophils. In mice, bovine LF has been shown to induce both mucosal and systemic immune responses (Debbabi et al., 1998). Cell-culture studies have demonstrated that LF and peptides derived from LF influence the production of various cytokines which regulate the immune and inflammatory responses of the body (Crouch et al., 1992 Shinoda et al., 1996). 

The discovery of vaccines for smallpox, cholera, and typhoid and the variety of vaccines now available have led to a significant reduction in the mortality and morbidity due to many diseases, with smallpox being the first to have been completely eradicated and poliomyelitis targeted to be the next. At present, the World Health Organization is working toward the complete elimination of poliomyelitis throughout the world [188,189], However, since Jenner discovered the vaccine for smallpox more than two centuries ago [190], only some 50 vaccines have been approved for use, and few additional vaccines have been discovered. Most of those in current use are administered parenterally they can induce only a systemic immune response, not mucosal immunity. Obviously the latter is very important in the prevention and treatment of infectious diseases, be they due to viral, bacterial, or parasitic pathogens that attack via the mucosal surfaces [190],... 

However, the nasal epithelium has little ability to break down drugs. The extensive mucosal surface of the nose has a lining of pseudostratified epithelium as well as cilia and the goblet cells involved in the secretion of mucus. The lymphoid tissue primarily involved in the mucosal immune responses is the mucosal-associated lymphoid tissue (MALT). The different regions of the respiratory tract that play an influencing role in the immune system are as follows ... 

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