T1 Immune Dysfunction

Question 1

Define hypersensitivity

Answer 1

Immune system occurs when the normal immune mechanisims produce an exaggerated response to an antigen, or an inappropriate response to self-antigens.

Question 2

Define alloimmunity

Answer 2

Alloimmunity is a type of delayed hypersensitivity (type IV) reaction cause by a reaction of immune system to antigens on transplanted cells from the same species.

Question 3

Define autoimmune disorder

Answer 3

Disease occurrs with the loss of the immune systems ability to distinguish self from non-self.

Question 4

Define immunodeficiency

Answer 4

Is the state where the immune system is unable to response appropriately because apart of the system is defective, missing or has been compromised by disease.

Question 5

Define B and T cells

Answer 5

B cells: responsible for humoral immunity

T cells: are involved in cell-mediated immunity.

Question 6

Define Plasma cell

Answer 6

B lymphocytes which have been turned into plasma cells. Which are antibody producing factories.

Question 7

Describe the four types of hypersensitivity disorders.

Answer 7

ABCD

1. Allergic anaphylaxis and atropy
2. Cytotoxic (antiBody)
3. Complex mediated (immune Complex)
4. Cell mediated (Delayed)

Question 8

Explain the function of different types of cells involved in humoral and cell-mediated immunity

Answer 8

Macrophages: detection, phagocytosis and destruction of bacteria
NK cells: cytotoxic contain proteins such as perforin and proteases in their cytoplasm
Cytotoxic T-lymphocytes: bind infected cells and induce apoptosis

Question 9

Explain how B and T cells of the adapted immune system become activated in response to an antigen.

Answer 9

ResearchMHC Proteins?

Question 10

Compare the difference between the primary and secondary humoral response

Answer 10

Primary: several days to produce antibodies and they are rarely enough.

Secondary humoral response: Only takes several hours to evoke a response and produces massive amounts of antibodies

Question 11

Contrast the difference between natural and acquired immunity

Answer 11

Naturally acquired - Active: infection contact with a pathogen.
Passive: antibodies pass from moth to fetus via placenta or via breast milk.
Artificially acquired - Active: Vaccine; dead or attenuated pathogen. Passive: Injection of immune serum.

Question 12

Provide examples of active and passive ways of acquiring immunity. (natural and acquired immunity).

Answer 12

Naturally acquired - Active: Flu, contact with pathogen via droplet.
Passive: Placental transfer of IgG from other to fetus during pregnancy.
Artificially acquired - Active: Immunisations
Passive: Antivenom from a snake transferred to a humam

Question 13

Providing an example of each, describe the four types of hypersensitivity disorders.

Answer 13

Type I - allergic response: histamin
Type II - Hemolytic diease of a new born, allergy to anaesthetics
Type III Immune complex: Rheumatoid arthritis

Question 14

What is an auto immune disease?

Answer 14

Loss of the immune systems ability to distinguish self from non-self.

Question 15

How does adrenaline reduce the signs and symptoms in patients suffering from anaphylactic shock?

Answer 15

Epipen = epinephrine. Adrenaline decreases ↑ vascular permeability and the vasodilation that occurs during anaphylaxis.
Adrenaline activates receptors in lings whihc relax bronchial smooth muscle. thereby relieving bronchospasm, increasing vital capacity.

Question 16

Contrast between primary and secondary immunodeficiencies.

Answer 16

Primary immunodeficiencies - genetic

Secondary immunodeficiencies - acquired extrinsicly.

Question 17

Outline the pathogenesis of HIV infection to the development of AIDS. In your answer be sure to include the critical cellular changes that occur following HIV infection

Answer 17

1. Acute HIV infection
2. Chronic HIV infection
3. Acquired immunodeficiency syndrome (AIDS).

HIV is a RNA virus, AIDS is a condition cause from chronic overuse of antiviral medications. HIV targets helper T (Th) cells, Other cells
bearing CD41 receptors, such as macrophages and dendritic
cells, also become infected by HIV. Attachment to the CD41
receptor and a co-receptor of the integral membrane protein
family, called C-chemokine receptor 5 (CCR5), is the means by
which the virus infects cells.
After infection, cellular and humoral immune processes
become progressively weakened, leaving the affected person
vulnerable to opportunistic infections,