Advanced and Clinical Immunology - Essay Example

Advanced and Clinical Immunology 1. Which allergens was Christopher diagnostically shown to be sensitive too? (5 Marks) Food allergens, this is because he tested positive for allergen specific IgE, in addition his medical history and physical examination showed a high reaction after consuming certain foods (Cox, et al, 2008). 2. Give an explanation to why Christopher has positive allergen specific IgE to house-dust mites but does not respond to these allergens in the skin prick test (SPT). (10Marks). ANSWER= 50 WORDS Skin prick testing is mostly used to assume the presence of allergen-specific IgE, In eosinophilic esophagitis patients, who often exhibit polysensitization where test results, show a high degree of predictive assessment for aeroallergens but a meagre predictive value for food allergens thus this suggests that skin prick test most likely identifies IgE reactivity towards aeroallergens in adult eosinophilic esophagitis but not for foods. Consequently, IgE immunoblotting were mainly required for determination of the foods to evade in trying to help the patient feel better ((Phipatanakul et al, 2004). 3. What are the major allergens of milk, eggs and peanut and why should there also be responses to other tree nuts if positive to peanut? (10marks). ANSWER= 50 WORDS Proteins are the chief food allergen in milk, eggs and peanuts. There is response to other tree nut because in some food groups an allergy to one member of a food family results to the individual being allergic to other members or elements of the same group. It’s also known as cross-reactivity (Spergel et al, 2005). 4. Th-2 like cells can be identified in the peripheral blood and lesions of atopic-dermatitis patients producing IL-4, 5, 13 and also IL-17 from Th17 cells. Explain the role(s) of these cytokines in allergy (10 Marks). ANSWER= 50 WORDS IL-4, 5, 13 are important for allergic responses and elimination of parasites. Th17 cells are the newest members of the Th cell family and produce the IL-17. The Th17 cells is involved in host defence with a role of protection against extracellular bacteria through activity on both the immune and non-immune cells, they have also began to be associated with the pathophysiology development of allergic diseases such as atopic dermatitis (Cox, et al, 2008). 5. Explain the significance of undertaking allergen-induced Basophil histamine, Mast cell PGD2 and Eosinophil Cationic Protein (ECP) release assays in allergy/asthma (15 Marks). ANSWER= 80 WORDS Mast cells PGDs, Basophil histamine and Eosinophil Cationic Protein (ECP) are essential constituents of allergic inflammation. Succeeding fixation of IgE to FceRI receptors on mast cells and basophil histamine is vital to the initiation and proliferation of immediate hypersensitivity reactions. Mast cells, basophils and the eosinophils are major effector cells in the allergic inflammation (Yazdanbakhsh et al, 2002). Mast cells indirectly contribute in asthmatic reactions. Its presence causes A, when the activation by multivalent Ag and the IgE, mast cells produces many inflammatory mediatorsm, which includes histamines, eicosanoids and proteases with PGD2 in high quantity. When asthmatic episodes are serious or acute, mast cells produces PGD2, which moves to the lungs hence causing bronchoconstriction (Cox, et al, 2008). PGD2, as well as histamine directly activates eosinophils, promotes their recruitment, and affects other vital parameters of lung inflammation, in particular vascular permeability. The role or function of PGD2 in eosinophilia and lung allergic response and its significant when conducting an assay is for detection of asthmatic reactions. 6. Outline the “Hygiene Hypothesis” in relation to allergic disease prevalence (15 Marks). ANSWER=80 WORDS According to the “Hygiene Hypothesis” the diminishing frequency of infections in Western countries and again in developing countries is as a result of origin of the cumulative occurrence of both autoimmune and the allergic ailments (Weiss, 2002). The hypothesis is grounded upon epidemiological data, mostly migration studies, which shows that individuals migrating from a low-incidence to a high-incidence country acquire the immune disorders with a higher rate at the first generation (Phipatanakul, 2004).The hygiene hypothesis further explains that changes in human lifestyle in developed countries have led to a reduction of infectious burden (Yazdanbakhsh et al, 2002). This is mainly associated with the rise of allergic and also autoimmune diseases. 7. Topical steroids were effective in reducing the eczema associated with Christopher’s atopic dermatitis. Why? (10 marks) ANSWER=50 WORDS Topical steroids provide symptomic relief for pruritis, erythema, inflammation and scratching, which were some of Christopher’s conditions. Management of eczema with steroid-based corticosteroids moreover meant liberation from the constant itching and the accompanying redness of the affected parts and also the scaly skin patches of eczema (Phipatanakul et al, 2004). 8. What are the immunological changes associated with monoclonal anti-IgE antibody (Omalizumab) treatment of allergic patients? (10 Marks). ANSWER=50 WORDS Omalizumab treatment induces major inhibition of stimulated IgE release thus immunological influences of omalizumab treatment, leads to a down regulation of IgE secretion and reduction of lymphocyte subpopulations (B-cells) indicating their anti-inflammatory potency (Cox, et al, 2008). There is also a decrease in circulating free IgE during omalizumab treatment though little is known about it. 9. Would Christopher be a good candidate for Allergen Specific Immunotherapy (SIT), explain your answer and the changes you might expect in terms of cytokines and immunoglobulin’s (15 Marks). ANSWER 80 WORDS Yes he would be a good candidate for Allergen Specific Immunotherapy (SIT), this is because he developed an allergic disease, which is basically an immunologic disorder linked to the activation of a distinct cytokine pattern in T cells, which involves secretion of certain allergic inflammatory cytokines particularly IL-4, IL-5 and IL-13 (Cox, et al, 2008). SIT represents the only curative way for specific type I allergy so far as much his symptoms are immediate and late-type, allergy reactions are amended by various pharmacological treatments. An upsurge in allergen-blocking IgG antibodies especially the IgE4 class leads to reduction in the number of mast cells and eosinophils (Weiss, 2002). Figure 1 diagram of the stages that lead to atopic dermatitis Figure 2 shows atopic dermatitis on the chest of a patient List of References Cox, et al. Pearls and pitfalls of allergy diagnostic testing. Annals of Allergy, Asthma & Immunology. 2008. 101(6): 580-590 Phipatanakul, W, Celedón J, Raby BA, et al.: Endotoxin exposure and eczema in the first year of life. Pediatrics 2004, 114:13–18. Spergel, J, Beausoleil, J and Pawlowski, N. Resolution of childhood peanut allergy. An Allergy Asthma Immunol 2000, 85:473–476 Weiss S. Eat dirt: the hygiene hypothesis and allergic diseases. N Engl J Med. 2002; 347:929-1. Yazdanbakhsh, M, Kremsner PG, van Ree R. Allergy, parasites, and the hygiene hypothesis. Science. 2002; 296:490-4 Read More