Micro Ch 13 HW (Mastering)

Define "serum sickness." What are some of its symptoms?

- Occurs following administration of a drug, antitoxin, or antivenom. - Due to antibody-target complexes lodging in vessels or joints. - Rash, fever, fatigue, achiness in joints and muscles, headache, labored breathing (dyspnea), and abdominal pain.

What is the difference between a primary immunodeficiency and a secondary immunodeficiency?

A *primary immunodeficiency* is a 𝘤𝘰𝘯𝘨𝘦𝘯𝘪𝘵𝘢𝘭 immunodeficiency leading to decreased immunity, whereas a *secondary immunodeficiency* is an immunodeficiency that is 𝘢𝘤𝘲𝘶𝘪𝘳𝘦𝘥 later in life.

Definition of "nonautoimmune type IV hypersensitivity."

A 𝘥𝘦𝘭𝘢𝘺𝘦𝘥, T cell-mediated hypersensitivity in which T cells respond to non-self antigens, typically haptens bound to larger carrier molecules.

__________ are transplants from self. No rejection reactions will occur.

Autografts

Which of the following occurs upon a secondary exposure to an allergen such as pollen? (Assume sensitization has already occurred.) *-* Complement lyses mast cells. *-* IgE antibodies are produced by plasma cells. *-* Cytotoxic T cells lyse plasma cells. *-* Degranulation of mast cells.

Degranulation of mast cells.

Which of the following scenarios is most concerning for development of hemolytic disease of the newborn? An Rh (*+* or *-*) mother pregnant with an Rh (*+* or *-*) fetus.

Rh- mother Rh+ fetus.

Which one of these is NOT a step in Type III Hypersensitivity Reactions? *-* Leukocytes release cytokines and promote inflammation. *-* Soluble antigen-antibody complexes form. *-* Complement activates inflammation cascades. *-* Deposition of antigen-antibody complexes in tissue attracts complement.

Soluble antigen-antibody complexes form. 𝘊𝘰𝘳𝘳𝘦𝘤𝘵 𝘱𝘳𝘰𝘤𝘦𝘴𝘴 𝘰𝘧 𝘛𝘺𝘱𝘦 𝘐𝘐𝘐 𝘏𝘺𝘱𝘦𝘳𝘴𝘦𝘯𝘴𝘪𝘵𝘪𝘷𝘪𝘵𝘺 𝘙𝘦𝘢𝘤𝘵𝘪𝘰𝘯𝘴: *1.* 𝘐𝘯𝘴𝘰𝘭𝘶𝘣𝘭𝘦 antigen-antibody complexes form. *2.* Deposition of insoluble antigen-antibody complexes in tissue attracts complement. *3.* Complement activates inflammation cascades and recruits leukocytes to the tissues. *4.* Leukocytes release cytokines and promote inflammation.

Define "the hygiene hypothesis."

The hygiene hypothesis states that: the higher proportion of allergies and autoimmunity observed in developed countries may be attributed to shifts in microbiota profiles.

__________ hypersensitivity reactions are driven by IgE interacting with soluble antigens.

Type I

__________ hypersensitivity reactions are driven by IgG or IgM interacting with nonsoluble antigens on cellular surfaces or extracellular antigens (i.e., connective tissue proteins).

Type II

__________ hypersensitivity reactions are driven by IgG or IgM interacting with soluble antigens.

Type III

Which of the following hypersensitivity classes is properly listed with its description? *-* Type II, allergies *-* Type III, immune complex *-* Type I, delayed hypersensitivity *-* Type IV, cytotoxic

Type III, immune complex ~Corrected List~ Type I, allergies Type II, cytotoxic Type III, immune complex Type IV, delayed hypersensitivity

In 1984, in one of the most famous cross-species transplantations, a baboon heart was transplanted into an infant (Baby Fae). This surgery is an example of which of the following types of grafts? *-* Xenograft *-* Autograft *-* Allograft *-* Isograft

Xenograft - Transplantations can either come from human (self, identical twin, or non-identical sources) or non-human sources. - *Autograft:* transplants from self; no rejection reactions will occur. - *Isograft:* transplanted tissue from an identical twin; typically safe from immune rejection. - *Allograft:* similar to the host, but not genetically identical; the closer the MHC match to the host, the higher the chance they will be tolerated. - *Xenograft:* interspecies transplants; e.g., pig heart valves used in humans.

__________ are interspecies transplants.

Xenografts

Define *cytolytic reaction* and *noncytolytic reaction*. List examples of diseases for each.

*Cytolytic reaction:* the target cell is lysed either by complement or recruited leukocytes. - Hemolytic disease of the newborn - Goodpasture syndrome - Autoimmune hemolytic anemia - Rheumatic heart disease *Noncytolytic reaction:* antibody-receptor interaction leads to receptor inactivation or overactivation as opposed to cell lysis. - Grave's disease - Myasthenia gravis

Define "systemic anaphylaxis."

- Anaphylactic shock. - A system-wide, potentially life-threatening response to an allergen.

Which of the following statements best describes the hygiene hypothesis as it relates to allergies? *-* The decreased incidence of hypersensitivities seen in developed countries is attributable to the decreased number of microbial infections. *-* As a result of increased antibiotic usage and cleaner foods and beverages, our normal gut microbiota has shifted, resulting in increased hypersensitivities in developed countries. *-* As a result of increased handwashing and improved universal healthcare precautions, the incidence of allergies and autoimmune disorders has decreased in developed countries. *-* As a result of poorer, unsanitary living conditions, the number of allergies and autoimmune disorders has increased in developed countries.

As a result of increased antibiotic usage and cleaner foods and beverages, our normal gut microbiota has shifted, resulting in increased hypersensitivities in developed countries.

__________ hypersensitivity reactions are driven by T cells interacting with soluble or cell- or matrix-bound antigens.

Type IV

__________ are similar to the host, but not genetically identical. The closer the MHC match to the host, the higher the chance they will be tolerated.

Allografts

Which of the following type II hypersensitivities is noncytolytic? *-* Hemolytic disease of the newborn *-* Goodpasture syndrome *-* Autoimmune hemolytic anemia *-* Grave's disease

Grave's disease

*SATA:* Which of the following types of hypersensitivity reactions involves production of antibodies? *-* Type I hypersensitivity *-* Type II hypersensitivity *-* Type III hypersensitivity *-* Type IV hypersensitivity

*-* Type I hypersensitivity *-* Type II hypersensitivity *-* Type III hypersensitivity - Based on the Gell and Coombs classification system, there are four classes of hypersensitivity reactions. - Antibodies are key participants in the first three classes of hypersensitivities, while T cells mediate type IV reactions.

Based on the Gell and Coombs classification system, there are 4 classes of hypersensitivity reactions. Which class(es) involve the production of antibodies, and which class(es) do NOT involve the production of antibodies?

*Antibodies:* - Type I: IgE - Type II: IgG or IgM - Type III: IgG or IgM *NO Antibodies:* - Type IV: T cells

*SATA:* Which of the following is a mechanism through which a type II hypersensitivity cytotoxic reaction works? *-* After activation by an antigen-antibody complex, leukocytes are recruited to trigger target cell lysis. *-* After activation by an antigen-antibody complex, complement proteins form a membrane attack complex to lyse target cells. *-* After activation by an antigen-antibody complex, complement proteins opsonize the target cell. *-* Antibody binding to host cell receptor triggers over-activation of receptor.

*-* After activation by an antigen-antibody complex, leukocytes are recruited to trigger target cell lysis. *-* After activation by an antigen-antibody complex, complement proteins form a membrane attack complex to lyse target cells. *-* After activation by an antigen-antibody complex, complement proteins opsonize the target cell. - Type II hypersensitivities can either be cytotoxic (ending in target cell lysis) or noncytotoxic. - Cytotoxic reactions may occur either through activation of a complement cascade or through recruitment of phagocytes to destroy target cells. - In the case of the complement cascade, cell lysis is triggered via opsonization, encouraging phagocytosis, or formation of a membrane attack complex that will directly lyse target cells. - These cytotoxic pathways are initially triggered by an antibody binding to an antigen. - A third way for type II reactions to inflict damage occurs without causing cytolysis. - This route usually has an autoimmune basis, with antibodies interacting with a cell-surface receptor on self-cells. - Rather than causing cell lysis, the antibody--receptor interaction causes either a receptor inactivation or receptor over-activation.

*SATA:* Which of the following is an example of a Type I hypersensitivity reaction? *-* Atopic eczema *-* Atopic asthma after exposure to pet dander *-* Anaphylactic shock following injection of bee venom *-* Serum sickness

*-* Atopic eczema *-* Atopic asthma after exposure to pet dander *-* Anaphylactic shock following injection of bee venom - Type I hypersensitivity reactions include localized allergic reactions such as atopic asthma (allergy-based asthma) and atopic dermatitis, but they also include systemic anaphylaxis. - Serum sickness is an example of Type III.

*SATA:* Which of the following is an example of an autoimmune disorder? *-* Following an untreated case of strep throat, your patient develops rheumatic heart disease. *-* After infection with Zika Virus, your patient develops Guillain-Barré syndrome. *-* Your patient is born with X-linked agammaglobulinemia. *-* Your juvenile patient develops Type I diabetes mellitus.

*-* Following an untreated case of strep throat, your patient develops rheumatic heart disease. *-* After infection with Zika Virus, your patient develops Guillain-Barré syndrome. *-* Your juvenile patient develops Type I diabetes mellitus. - Autoimmune disorders are immune dysfunctions in which the immune system attacks healthy self-tissues, leading to chronic inflammation, joint and muscle pain, organ dysfunction, and tissue damage. - Other examples: multiple sclerosis, celiac disease, lupus, Graves' disease, rheumatoid arthritis.

*SATA:* Which of the following measures can be used to diagnose allergies? *-* A decreased heart rate of less than 50 beats per minute *-* Large wheal and flare lesion following a skin prick test *-* An elevated blood pressure reading of greater than 170 mm Hg (systolic)/100 mm Hg (diastolic) *-* Elevated IgE titers within the patient's serum to a specific allergen

*-* Large wheal and flare lesion following a skin prick test *-* Elevated IgE titers within the patient's serum to a specific allergen - Allergies are commonly measured using both skin tests and blood tests. - Blood tests look for elevated IgE antibody titers against specific allergens. - Skin tests examine the extent of the wheal and flare lesion following a skin/prick test, intradermal test, or patch test. - A larger area indicates increased sensitivity to the allergen.

*SATA:* Which of the following would be an appropriate form of treatment for a patient suffering from serum sickness following administration of botulism antitoxin? *-* Administration of more antitoxin *-* Prednisone (a corticosteroid) *-* Valproate (an anticonvulscent) *-* Ibuprofen (a non-steroidal anti-inflammatory drug)

*-* Prednisone (a corticosteroid) *-* Ibuprofen (a non-steroidal anti-inflammatory drug) - A negative side effect to using antivenoms, antitoxins, and certain other medications is that serum sickness can result. - In this condition, the patient's immune system recognizes the administered substance as foreign. - About three weeks after an initial exposure, the patient forms antibodies against the drug, antivenom, or antitoxin. - As the antibodies bind to their targets, the immune complexes become lodged in vessels or joints, producing symptoms such as rash, fever, fatigue, achiness in joints and muscles, headache, dyspnea, and abdominal pain. - 𝘚𝘦𝘳𝘶𝘮 𝘴𝘪𝘤𝘬𝘯𝘦𝘴𝘴 𝘪𝘴 𝘵𝘳𝘦𝘢𝘵𝘦𝘥 𝘸𝘪𝘵𝘩 𝘢𝘯𝘵𝘪-𝘪𝘯𝘧𝘭𝘢𝘮𝘮𝘢𝘵𝘰𝘳𝘺 𝘥𝘳𝘶𝘨𝘴 (𝘴𝘵𝘦𝘳𝘰𝘪𝘥𝘢𝘭 𝘰𝘳 𝘯𝘰𝘯𝘴𝘵𝘦𝘳𝘰𝘪𝘥𝘢𝘭) 𝘢𝘯𝘥 𝘢𝘯𝘵𝘪𝘩𝘪𝘴𝘵𝘢𝘮𝘪𝘯𝘦𝘴. - Fortunately, most patients fully recover within a week and have no further symptoms once exposure to the causative substance is stopped.

*SATA:* Which of the following is an example of a type III hypersensitivity? *-* Hemolytic disease of the newborn *-* Graft-versus-host disease *-* Scleroderma *-* Rheumatoid arthritis

*-* Scleroderma *-* Rheumatoid arthritis - A number of autoimmune diseases are characterized by type III reactions. - Examples include systemic lupus erythematosus, rheumatoid arthritis, scleroderma, Sjögren's syndrome, and poststreptococcal glomerulonephritis. - 𝘛𝘺𝘱𝘦 𝘐𝘐: Hemolytic disease of the newborn. - 𝘛𝘺𝘱𝘦 𝘐𝘝: Graft-versus-host disease.

*SATA:* Which key symptoms would you typically expect with a patient who has a severe, post-sensitizing allergic reaction to peanuts? *-* Tachycardia *-* Urticaria *-* Hypertension (increased blood pressure) *-* Dyspnea

*-* Tachycardia *-* Urticaria *-* Dyspnea - Patients with systemic anaphylaxis will often have signs and symptoms affecting several anatomical systems and sites, including: - the skin (such as urticaria, pruritus, flushing, and angioedema), - the respiratory system (such as a swollen itchy throat, dysphonia, dyspnea, and bronchospasm), - the central nervous system (such as anxiety, dizziness, syncope, confusion, and intense headache), - the cardiovascular system (such as chest pain, decreased blood pressure, tachycardia, and weak pulse), - and the gastrointestinal system (such as nausea, vomiting, cramping, and diarrhea).

Which of the following statements concerning desensitization therapy is true? *-* Desensitization therapy involves exposing patients to decreasing concentrations of an allergen over time (beginning with a concentrated dose of the allergen) in hopes of decreasing the allergic response. *-* Desensitization therapy provokes a TH2 cell response. *-* Desensitization therapy is most effective for food allergies. *-* Desensitization therapy encourages plasma cells to produce IgG antibodies against the allergen.

Desensitization therapy encourages plasma cells to produce IgG antibodies against the allergen. - Desensitization involves exposing the patient to 𝘨𝘳𝘦𝘢𝘵𝘦𝘳 𝘢𝘯𝘥 𝘨𝘳𝘦𝘢𝘵𝘦𝘳 𝘢𝘮𝘰𝘶𝘯𝘵𝘴 of the allergen over time until the patient's immune response is altered. - T-reg cells 𝘥𝘪𝘴𝘤𝘰𝘶𝘳𝘢𝘨𝘦 TH2 cell activity. - Most food allergies are only 𝘸𝘦𝘢𝘬𝘭𝘺 𝘳𝘦𝘴𝘱𝘰𝘯𝘴𝘪𝘷𝘦.

Which of the following is an example of a non-autoimmune type IV hypersensitivity? *-* Hashimoto thyroiditis *-* Guillain-Barré syndrome *-* Celiac disease *-* Graft-versus-host disease

Graft-versus-host disease - Other examples of non-autoimmune type IV hypersensitivity include: - Tuberculin skin test (PDD test). - Contact dermatitis. - Transplant rejection.

Which of the following mechanisms occurs in a patient suffering from systemic lupus erythematosus? *-* Insoluble antigen-antibody complexes form and deposit in tissues, attracting complement, which in turn activates inflammation cascades and recruits inflammation-promoting leukocytes. *-* Cytotoxic T cells lyse target host cells after activation by TH1 helper cells. *-* Complement is recruited by antigen-antibody complexes and ultimately lyses host cells. *-* IgE antibodies with antigen bound will trigger degranulation of mast cells.

Insoluble antigen-antibody complexes form and deposit in tissues, attracting complement, which in turn activates inflammation cascades and recruits inflammation-promoting leukocytes. - Type III Hypersensitivity Reaction

__________ are transplanted tissue from an identical twin. These are typically safe from immune rejection.

Isografts

Which of the following statements regarding type IV hypersensitivities is true? *-* An example of a nonautoimmune type IV hypersensitivity is serum sickness. *-* Type IV hypersensitivities are delayed and typically manifest slowly over 12-72 hours after the stimulating antigen is encountered. *-* Type IV hypersensitivities consist of only nonautoimmune hypersensitivities, as autoimmune hypersensitivities are exclusively classified as type III hypersensitivities. *-* Type IV hypersensitivities are antibody-mediated.

Type IV hypersensitivities are delayed and typically manifest slowly over 12-72 hours after the stimulating antigen is encountered. - 𝘚𝘦𝘳𝘶𝘮 𝘴𝘪𝘤𝘬𝘯𝘦𝘴𝘴 is an example of 𝘛𝘺𝘱𝘦 𝘐𝘐𝘐. - Type IV are often called delayed hypersensitivity reactions. - Type IV 𝘮𝘢𝘺 𝘣𝘦 𝘢𝘶𝘵𝘰𝘪𝘮𝘮𝘶𝘯𝘦 𝘰𝘳 𝘯𝘰𝘯𝘢𝘶𝘵𝘰𝘪𝘮𝘮𝘶𝘯𝘦. - Autoimmune examples: MS, Hashimoto thyroiditis, Guillain-Barre syndrome, T1DM, celiac disease. - Nonautoimmune examples: tuberculin skin (PPD) test, contact dermatitis, transplant rejection, graft-versus-host disease (GVHD). - Type IV are 𝘮𝘦𝘥𝘪𝘢𝘵𝘦𝘥 𝘣𝘺 𝘛 𝘤𝘦𝘭𝘭𝘴 (out of the 4 types, Type IV is the only one NOT antibody-mediated).

Which of the following scenarios is an example of a primary immunodeficiency? *-* Your patient acquires HIV-AIDS later in life and has a resulting low CD4 T cell count. *-* Your patient is born with agammaglobulinemia, a genetic condition that leads to decreased antibody production. *-* An individual is given cyclosporine to prevent host-versus-graft disease during a kidney transplantation. *-* A patient has an atopic response to penicillin and is given hydrocortisone cream to relieve inflammation.

Your patient is born with agammaglobulinemia, a genetic condition that leads to decreased antibody production.