Question 1

What is the mechanism in type IV hypersensitivity reactions?

Accepted Answer

In type IV hypersensitivity reactions, cytotoxic T lymphocytes or lymphokines-producing Th1 cells attack and destroy cellular targets directly. This type of reaction does not involve antibodies.

Question 2

In a type III hypersensitivity reaction,what causes the harmful effects after the immune complexes are deposited in tissues?

Accepted Answer

In a type III hypersensitivity reaction, the immune complexes that are deposited in tissues activate the complement system, leading to the formation of the membrane attack complex (MAC) and other components that can cause tissue damage and inflammation. This complement activation is the primary cause of the harmful effects in type III hypersensitivity reactions.

Question 3

Blood transfusion reactions are an example of:

Accepted Answer

Blood transfusion reactions involve an immune response to transfused blood that is recognized as foreign (non-self) by the recipient's immune system. This is an example of alloimmunity, which is an immune response to non-self antigens from individuals of the same species. Autoimmunity occurs when the immune system attacks self-antigens, and homoimmunity, while not a commonly used term, would refer to an immune response to self-antigens within an individual.

Question 4

Which component of the immune system is deficient in people with infections caused by viruses,fungi,or yeast?

Accepted Answer

T cells are responsible for cell-mediated immune responses, which are important for fighting infections caused by viruses, fungi, and yeast. B cells are responsible for antibody-mediated immune responses, which are important for fighting infections caused by bacteria and viruses. Natural killer cells and macrophages also play a role in the immune response against these types of infections, but their deficiency alone would not necessarily result in susceptibility to viral, fungal, or yeast infections.

Question 5

When a tuberculin skin test is positive,what forms the hard center and erythema surrounding the induration?

Accepted Answer

T lymphocytes and macrophages migrate to the site of the skin test antigen and release cytokines, triggering an immune response that results in the formation of a hard center (induration) and erythema surrounding it. The other options do not play a direct role in the formation of this reaction.

Question 6

In Graves' disease (hyperthyroidism),autoantibodies bind to and activate receptors for thyroid stimulating hormone (TSH)so that excessive T₄ (thyroxine)is secreted,causing clinical manifestations of an increased metabolism.This mechanism is an example of which Type II hypersensitivity reaction?

Accepted Answer

In Graves' disease, the autoantibodies modulate the function of the TSH receptor by stimulating it, leading to increased thyroid hormone production. This is an example of modulation in Type II hypersensitivity.

Question 7

When the maternal immune system becomes sensitized against antigens expressed by the fetus,_____ disease is a result.

Accepted Answer

When the maternal immune system becomes sensitized against antigens expressed by the fetus, alloimmune disease is a result. Alloimmune disease occurs when the immune system of one individual considers the tissues of another individual to be foreign and attacks them. In the case of pregnancy, this can occur when the mother's immune system recognizes fetal antigens as foreign and mounts an immune response against them leading to pregnancy complications.

Question 8

A person with type O blood is likely to have high titers of anti-___ antibodies.

Accepted Answer

Type O blood lacks both A and B antigens, so individuals with type O blood will develop antibodies against both A and B antigens. Therefore, they will have high titers of anti-A and anti-B antibodies in their blood.

Question 9

Which blood cell carries the carbohydrate antigens for blood type?

Accepted Answer

Erythrocytes, also known as red blood cells, carry the carbohydrate antigens for blood type. The antigens are located on the surface of the cell membrane and determine an individual's blood type. Platelets, neutrophils, and lymphocytes do not carry these antigens.

Question 10

What disease involves the deposition of circulating immune complexes containing an antibody against host DNA,resulting in tissue damage?

Accepted Answer

Systemic lupus erythematosus (SLE) is an autoimmune disease where the immune system attacks the body's own tissues, resulting in the deposition of circulating immune complexes containing an antibody against host DNA, which can lead to tissue damage. Hemolytic anemia, pernicious anemia, and myasthenia gravis are other autoimmune diseases, but they do not involve these specific immune complexes.

Question 11

The class of antibody involved in type I hypersensitivity reactions is:

Accepted Answer

IgE antibodies play a key role in type I hypersensitivity reactions, such as allergies and anaphylaxis. They bind to mast cells and basophils, activating them to release histamine and other inflammatory mediators.

Question 12

How does tissue damage occur in acute rejection after an organ transplant?

Accepted Answer

In acute rejection after an organ transplant, helper T cells (Th1) release cytokines that activate infiltrating macrophages and cytotoxic T cells, which directly attack the endothelial cells of the transplanted tissue. This leads to tissue damage.

Question 13

What is the mechanism in type III hypersensitivity reactions?

Accepted Answer

In type III hypersensitivity reactions, antibodies bind to soluble antigens that were released into body fluids, forming immune complexes that can't be properly cleared by the body. These immune complexes are then deposited in the tissues, leading to an inflammatory reaction and tissue damage.

Question 14

Considering the effects of nutritional deficiencies on the immune system,severe deficits in calories and protein lead to deficiencies in the formation of which immune cells?

Accepted Answer

Severe deficits in calories and protein lead to deficiencies in the formation of T cells, which are important for cell-mediated immunity. Additionally, B cells and natural killer cells may also be affected by nutritional deficiencies, but they are not specifically mentioned as being impacted by deficits in calories and protein. Neutrophils primarily play a role in innate immunity and are not directly impacted by nutritional deficiencies in the same way that T cells are.

Question 15

By _____ months,the newborn is sufficiently protected by antibodies produced by its own B cells.

Accepted Answer

By 6 to 8 months, the newborn's own B cells have developed sufficiently to produce enough antibodies to protect them from infections on their own. Prior to this, the newborn relies on antibodies acquired from their mother during pregnancy or while breastfeeding.

Question 16

In myasthenia gravis,the acetylcholine receptor antibodies block acetylcholine from attaching to their receptors impairing the neuromuscular transmission and causing muscle weakness.This mechanism is an example of which Type II hypersensitivity reaction?

Accepted Answer

In myasthenia gravis, the antibodies modulate the function of the acetylcholine receptors by blocking acetylcholine binding, which is an example of modulation in Type II hypersensitivity.

Question 17

In a Type II hypersensitivity reaction,that is an antibody-dependent cell-mediated cytotoxicity (ADCC),what destroys the target cells?

Accepted Answer

In a Type II hypersensitivity reaction, ADCC can be mediated by natural killer cells, which attach to the target cells and destroy them through release of cytotoxic granules containing perforin and granzyme. Complement-mediated cell lysis (A) is associated with Type I hypersensitivity reactions. Phagocytosis by macrophages (B) is part of Type III hypersensitivity reactions. Neutrophil granules and toxic oxygen products (C) are involved in Type III and Type IV hypersensitivity reactions.

Question 18

Deficiencies in which element can produce depression of both B- and T-cell function?

Accepted Answer

Zinc deficiency is known to impair the function of both B- and T-cells, leading to weakened immune response. Iron deficiency primarily affects the function of red blood cells and can lead to anemia, while iodine deficiency primarily affects the thyroid gland and can lead to hypothyroidism. Magnesium deficiency can also affect immune function, but it does not have as direct of an impact on B- and T-cell function as zinc deficiency.

Question 19

Which class of immunoglobulins forms isohemagglutinins?

Accepted Answer

Immunoglobulin M (IgM) forms isohemagglutinins, which are antibodies directed against common blood group antigens.

Question 20

What mechanism occurs in Raynaud phenomenon that classify it as a type III hypersensitivity reaction?

Accepted Answer

Raynaud phenomenon is characterized by the deposition of immune complexes in capillary beds, leading to obstruction of blood flow and tissue ischemia. This is known as a type III hypersensitivity reaction, which is mediated by the formation and deposition of antigen-antibody complexes. Mast cell degranulation (B) is associated with type I hypersensitivity reactions, while cytotoxic T lymphocytes (C) and antibodies (D) are involved in type IV hypersensitivity reactions.

Quiz 8: Alterations in Immunity and Inflammation Including Hypersensitivies

What is the mechanism in type IV hypersensitivity reactions?

In a type III hypersensitivity reaction,what causes the harmful effects after the immune complexes are deposited in tissues?

Blood transfusion reactions are an example of:

Which component of the immune system is deficient in people with infections caused by viruses,fungi,or yeast?

When a tuberculin skin test is positive,what forms the hard center and erythema surrounding the induration?

In Graves' disease (hyperthyroidism) ,autoantibodies bind to and activate receptors for thyroid stimulating hormone (TSH) so that excessive T₄ (thyroxine) is secreted,causing clinical manifestations of an increased metabolism.This mechanism is an example of which Type II hypersensitivity reaction?

When the maternal immune system becomes sensitized against antigens expressed by the fetus,_____ disease is a result.

A person with type O blood is likely to have high titers of anti-___ antibodies.

Which blood cell carries the carbohydrate antigens for blood type?

What disease involves the deposition of circulating immune complexes containing an antibody against host DNA,resulting in tissue damage?

The class of antibody involved in type I hypersensitivity reactions is:

How does tissue damage occur in acute rejection after an organ transplant?

What is the mechanism in type III hypersensitivity reactions?

Considering the effects of nutritional deficiencies on the immune system,severe deficits in calories and protein lead to deficiencies in the formation of which immune cells?

By _____ months,the newborn is sufficiently protected by antibodies produced by its own B cells.

In myasthenia gravis,the acetylcholine receptor antibodies block acetylcholine from attaching to their receptors impairing the neuromuscular transmission and causing muscle weakness.This mechanism is an example of which Type II hypersensitivity reaction?

In a Type II hypersensitivity reaction,that is an antibody-dependent cell-mediated cytotoxicity (ADCC) ,what destroys the target cells?

Deficiencies in which element can produce depression of both B- and T-cell function?

Which class of immunoglobulins forms isohemagglutinins?

What mechanism occurs in Raynaud phenomenon that classify it as a type III hypersensitivity reaction?

Quiz 8: Alterations in Immunity and Inflammation Including Hypersensitivies

What is the mechanism in type IV hypersensitivity reactions?

In a type III hypersensitivity reaction,what causes the harmful effects after the immune complexes are deposited in tissues?

Blood transfusion reactions are an example of:

Which component of the immune system is deficient in people with infections caused by viruses,fungi,or yeast?

When a tuberculin skin test is positive,what forms the hard center and erythema surrounding the induration?

In Graves' disease (hyperthyroidism) ,autoantibodies bind to and activate receptors for thyroid stimulating hormone (TSH) so that excessive T4 (thyroxine) is secreted,causing clinical manifestations of an increased metabolism.This mechanism is an example of which Type II hypersensitivity reaction?

When the maternal immune system becomes sensitized against antigens expressed by the fetus,_____ disease is a result.

A person with type O blood is likely to have high titers of anti-___ antibodies.

Which blood cell carries the carbohydrate antigens for blood type?

What disease involves the deposition of circulating immune complexes containing an antibody against host DNA,resulting in tissue damage?

The class of antibody involved in type I hypersensitivity reactions is:

How does tissue damage occur in acute rejection after an organ transplant?

What is the mechanism in type III hypersensitivity reactions?

Considering the effects of nutritional deficiencies on the immune system,severe deficits in calories and protein lead to deficiencies in the formation of which immune cells?

By _____ months,the newborn is sufficiently protected by antibodies produced by its own B cells.

In myasthenia gravis,the acetylcholine receptor antibodies block acetylcholine from attaching to their receptors impairing the neuromuscular transmission and causing muscle weakness.This mechanism is an example of which Type II hypersensitivity reaction?

In a Type II hypersensitivity reaction,that is an antibody-dependent cell-mediated cytotoxicity (ADCC) ,what destroys the target cells?

Deficiencies in which element can produce depression of both B- and T-cell function?

Which class of immunoglobulins forms isohemagglutinins?

What mechanism occurs in Raynaud phenomenon that classify it as a type III hypersensitivity reaction?