Immunodeficiency

Question 1

What are the Pattern recognition receptors

(PRR)?

Answer 1

Toll-like receptors (TLR’s), NOD-like receptoes (NLR’s), RigI-like receptors (RLR’s) C-type lectins (CLR’s), scavenger receptors

Question 2

What are some Antimicrobial peptides?

Answer 2

defensins, cathelin, protegrin, granulsyin, histatin, secretory leukoprotease inhibitor, and probiotics

Question 3

What are the cells involved in the innate immune system?

Answer 3

Macrophages, dendritic cells, NK cells, NK-T cells, neutrophils, eosinophils, mast cells, basophils, and epithelial cells

Question 4

What are Complement components?

Answer 4

Classic and alternative complement pathway, and proteins that bind complement components

Question 5

What are Cytokines?

Answer 5

Autocrine, paracrine, endocrine cytokines that mediate host defense and inflammation, as well as recruit, direct, and regulate adaptive immune responses

Question 6

What is the function of B lymphocytes?

Answer 6

B lymphocytes develop potential to secret antibodies: humoral immunity

Question 7

What is the function of Killer or cytotoxic T lymphocytes?

Answer 7

able to kill. Cellular immunity

Question 8

What is the function of Helper T lymphocytes?

Answer 8

ecrete growth factors (cytokines) which control immune response: Help B lymphocytes and T lymphocytes (Helper T cells are target of HIV)

Question 9

What is the function of Suppressor T lymphocytes?

Answer 9

may damp down immune response

Question 10

How does the binding of antibodies to antigens inactivate the antigens?

Answer 10

enhances phagocytosis by:

• neutralisation (blocking viral sites/coating bacteria)
• agglutination of microbes
• precipitation of dissolved antigens

also activated complement system leading to cell lysis

Question 11

How do cytotoxic T cells kill infected cells?

Answer 11

Once bound to the infected cell, perforin is released which makes holes in the infected cells membrane. Enzymes that promote apoptosis enter and the infected cell is destroyed.

Question 12

What is immunodeficiency?

Answer 12

Clinical situations where the immune system is not effective enough to protect the body against infection

Can occur at any age.
Remember that children and elderly are much more sensitive to infection.

Question 13

What are some causes of secondary or acquired immunodeficiencies?

Answer 13

Many causes; transient or long-lasting; minor or major.
Stress
Surgery/burns
Malnutrition
Cancer – especially lymphoproliferative disease
Immunosuppressive effect of drugs inc. cancer therapy
- Lymphocytes
- Neutrophils

Question 14

What is primary immunodeficiency?

Answer 14

Very rare - but even very rare diseases can occur anywhere.
Extensively studied - give important clues to the working of the immune system - experiments of nature.
Often diagnosed in early childhood but can present in adult life
Recurrent infection often suggests immunological problem

Question 15

What are the symptoms of chronic granulomatous disease?

Answer 15

Osteomyelitis
Pneumonia
Swollen lymph nodes
Ginigivitis
Non-malignant granulomas
Inflammatory bowel disease

Question 16

Which cells does X-linked agammaglobulinaemia affect?

Answer 16

primary B cells

Question 17

What are the symptoms of defects in T cells?

Answer 17

Symptoms are recurrent infection with opportunistic infections, bacteria, viruses,
Fungi (candida), protozoa (pneumocystis).

Question 18

Which cells do these diseases affect?

Adenosine Deaminase Deficiency
Purine Nucleoside Phosphorylase Deficiency
MHC Class II Deficiency
Wiskott-Aldrich Syndrome

Answer 18

Primary T cells