Antigens Administration

The route of antigen administration can alter the speed of antigen access to the circulation and, thus, the systemic symptoms in anaphylaxis models. For example, allergen ingestion typically induces anaphylaxis that includes gastrointestinal symptoms, such as diarrhea [4]. These intestinal anaphylaxis models in mice are dependent on IgE-induced mast cell activation, and the release of PAF and serotonin (rather than histamine) [1,4]. 

Organ weights (spleen, thymus, all animals) Immunotoxicity tests (1) functional tests (either a splenic plaque-forming cell (PEC) assay or an Enzyme-Linked Immunosorbent Assay (ELISA) to determine the response to antigen administration) (2) enumeration of splenic or peripheral blood total B cells, total T cells, and T-cell subpopulations Detailed clinical observations Functional observations (sensory reactivity to stimuli of different types, grip strength, motor activity, more specialized tests on indication)... 

The route of antigen administration depends on the nature of the antigen itself, the animal species, the use of an adjuvant, and the immunological response. When producing antisera from rabbits, subcutaneous and intradermal administration are the most popular routes. Intramuscular injections can be used in the presence of Freund adjuvants because this route provides rapid access to the lymphatic system. The intravenous route is used with particulate antigens because injection can produce a response, which, although rapid, is not sustained. 

Very high levels of antigen frequently favor the development of tolerance, whereas intermediate levels of antigen favor the development of an immune response. (3) Frequently, the route of antigen administration is critical in the development of tolerance. An intravenously injected antigen is more likely to promote a tolerant condition than antigen injected subcutaneously. 

Mucosal tolerance is a meanwhile well-accepted phenomenon, which was initially referred to as oral tolerance , because it was first recognized after feeding antigen [14], As immunological unresponsiveness - characterized by a refractory or diminished capability to develop an immune response upon systemic reexposure to the specific antigen - can also be achieved after antigen administration via the nasal, inhalative, rectal or genital route, it is now more broadly referred to as mucosal tolerance. 

The second pathway of slgA is via bile (Fig. 11.4) this has so far only been confirmed in laboratory animals, although it may occur in man. IgA receptors have been shown to occur in a range of cell types, including polymorphonuclear leukocytes, monocytes, lymphocytes, helper and suppressor cells it is not known if IgA receptors occur on Kupffer cells or other cells of the stationary reticuloendothelial system. It is important to note that slgA appears to be produced most effectively by local stimulation rather than by systemic infection or antigen administration (361). 

Jaganathan, K. S., and Vyas, S. P. (2006), Strong systemic and mucosal immune responses to surface-modified PLGA microspheres containing recombinant Hepatitis B antigen administrated intranasally, Vaccine, 24,4201 211. 

Zhang X, Izikson L, Liu L, Weiner HL Activation of CD25+CD4+ regulatory T cells by oral antigen administration. J Immunol 2001 167 4245 4253. 

Mechanism of action Rh GAM is a human IgG preparation that contains antibodies against red cell RhJD) antigens. Administration of this antibody to Rh (D)-negative. D -negative mothers at time of antigen exposure (ie, birth of an Rh (D)-positive, D -positive child) blocks the primaiy immune response to the foreign cells. The mechanism probably involves feedback immunosuppression. 

Aldesleukin (IL-2) and several other interleukins activate natural killer cells (NK cells) and lymphokine-activated killer cells (LAK cells promiscuous killers ). The investigational use of aldesleukin in AIDS patients is partly based on the fact that lymphocytes from such individuals produce significantly less IL-2 than lymphocytes from healthy controls. The answer is (A). RhJD) immune globulin contains antibodies against Rh (D) antigens. Administration to an Rh-negative mother within 72 hours after the birth of an Rh-positive baby prevents Rh hemolytic disease of the newborn (erythroblastosis fetalis) in subsequent pregnancies. The answer is (D). 

Type I reactions are those in which antibody is attached to the surface of a mast cell. Contact with antigen in solution results in release of the soluble mediators of anaphylaxis, producing in the skin the typical immediate weal and flare reaction. This commences within minutes of antigen administration, is maximal after 15-20 min, and is usually no longer detectable macroscopically after 1 hour. In humans, most immediate hypersensitivity is produced by antibodies of the IgE-class. However, in many animal species, similar reactions are commonly produced by IgG subclass antibodies. There is also some evidence that immediate-type reactions also can be produced occasionally in humans by non-reaginic IgG subclass antibodies (Parish, 1970). 

Anaphylactic reactions usually occur seconds to minutes after antigen administration, but late onset anaphylaxis can also occur, as in this case. 

PLGA nanoparticles have been utilized for treating the different kind cancer cell-lines which possess antigens or TLR ligands. These PLGA coupled nanoparticles will increase the immune when compared to antigen administration. (Anderson and Shive, 1999]. At the same time, it has some drawbacks such as immunosuppression. Currently researchers target towards the cancer therapy... 

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