Hypersensitivity Case Study Essay

*Poison Ivy- The bodys immune system is normally in the business of protecting us from bacteria, viruses, and other inappropriate invaders that dirty dog make us sick. But when urushiol from the envenom ivy coif preservees the scrape, it instigates an immune response, called dermatitis, to what would otherwise be a harmless substance. Hay feverishness is another example of this caseful of response in the case of hay fever, the immune system overreacts to pollen, or another plant-produced substance. Heres how the acerbate ivy response occurs. Urushiol makes its way down through the skin, where it is metabolized, or lost down. Immune cells called T lymphocytes (or T-cells) recognize the urushiol derivatives as a foreign substance, or antigen. They send out inflammatory signals called cytokines, which bring in white root cells.Under orders from the cytokines, these white blood cells turn into macrophages. The macrophages eat foreign substances, unless in doing so they also damage normal weave, resulting in the skin inflammation that occurs with poison ivy. The allergic reaction to poison ivy is know as delayed hypersensitivity. Unlike immediate hypersensitivity, which causes an allergic reaction deep down minutes of exposure to an antigen, delayed hypersensitivity reactions fag outt emerge for some(prenominal) hours or even days after the exposure. Most people dont beget a reaction the first time they touch poison ivy, but develop an allergic reaction after reiterate exposure. Everyone has a different sensitivity, and in that locationfore a slightly different reaction, to poison ivy. Sensitivity usually decreases with age and with repeat exposures to the plant.*Transfusing a person of vitrine A Blood with Type B Blood- ABO blood character system The ABO system consists of A, B, AB, and O blood figures. People with figure A have antibodies in the blood against type B. People with type B have antibodies in the blood against type A. People wi th AB have no anti-A or anti-B antibodies. People with type O have both anti-A and anti-B antibodies. People with type AB blood be called world(a) recipients, because they can receive any of the ABO types. People with type O blood are called universal donors, because their blood can be granted to people with any of the ABO types. Mismatches with the ABO and Rh blood types are responsiblefor the most serious, sometimes life-threatening, transfusion reactions.So unless the person is RH- there usually isnt that big of a reaction when An Type A is given Type B blood. These reactions may be mild or severe. Most mild reactions are not life-threatening when treated quickly. hitherto mild reactions, though, can be frightening. heartbreaking transfusion reactions can be life-threatening, but this is very rare. Mild allergic reactions may involve itching, hives, wheezing, and fever. Severe reactions may cause anaphylactic shock.Exposure to a field of bitterweed- Ragweed allergy, simila r to other pollen allergies, may include symptoms of allergic rhinitis, allergic pinkeye and allergic asthma. Symptoms caused by ragweed pollen allergy would be expected to sidetrack during August and September and last until October or November, depending on the climate. So catch out of a field of Ragweed during those times a course of study if you experience allergy or hypersensitivity around ragweed.*Unsuccessful Kidney Transplant- Transplant rejection is when transplanted weave is rejected by the recipients immune system, which destroys the transplanted tissue. Transplant rejection can be lessened by determining the molecular similitude in the midst of donor and recipient and by use of immunosuppressant drugs after transplant. Hyper-acute rejection occurs a few minutes after the transplant when the antigens are completely unmatched. The tissue must be removed right away so the recipient does not die. This type of rejection is seen when a recipient is given the wrong type of blood. For example, a person given type A blood when he or she is type B.