immune system overview

Question 1

name the 3 major functions of the immune system

Answer 1

1. protects against pathogens (virus, bacteria, fungi, protazoens, multicellular) and other immunogens
2. recognizes and removes abnormal self cells (cancer)
3. removes dead or damaged cells: scavenger cells (macrophages)

Question 2

recognize the innate and acquired immunity

Answer 2

broad specificity, recognizes pathogen associated molecular patterns (PAMP)
fast response
inflammation: red, warm, pain, cytokine mediated
(molecular pattern in many bacteria)

Question 3

recognize acquired (adaptive)

Answer 3

immune response directed at a specific pathogen, slow first response: takes days (very slow), memory (rapid subsequent responses), cell mediated verses humoral (antibody-mediated) immunity

Question 4

recognize the two lines of defense

Answer 4

1. physical and chemical barriers (epithelia, glandular secretions, gastric acidity
2. internal immune response- detection, cell-to-cell communication with pathogen, chemotaxis, recruitment and coordination (inflammation), destruction or suppression (tb, malaria, herpes), depend on cytokines and antibodies

Question 5

neutrophil

Answer 5

granulocyte/leucocyte, 3 lobes, 50-70% peripheral cell lymphocytes, first responder to inflammation, degranulate and releases cytokines (pyrogens and inflammatory mediators)
highly motile and phagocytic cells, short lived (only one involved in phagocytes!)

Question 6

eosinophil

Answer 6

granulocyte/leucocyte, 2 lobes

Question 7

basophil

Answer 7

granulocyte/leucocyte, 3 lobes

Question 8

monocyte

Answer 8

HUGE, agranulocyte, leukocyte

Question 9

immunogen

Answer 9

chemical compound that triggers an immune response

Question 10

epitope

Answer 10

one of the antigenic determinants of an antigen - potent immunogens have HMW - elicit the production of different specificity antibody

Question 11

haptens

Answer 11

some LMW molecules become immunogenic when linked to a carrier protein (penicillin)

Question 12

adjuvants

Answer 12

substances that enhance the immunogenicity of an antigen - capability of antigen to initiate an immune response - used in vaccine generation against antigen

Question 13

the bigger the molecule,

Answer 13

the more likely it can initiate an immune response

Question 14

dendritic cell

Answer 14

not leukocyte, Antigen presenting cells in many tissues (langerhan cells in skin)
Recognize and capture antigens, Migrate to secondary lymphoid tissues
Present antigens to lymphocytes, Antigen binding activates lymphocytes so they can proliferate and come into the bloodstream to fight that antigen

Question 15

primary lymphoid tissue

Answer 15

Thymus (produces T cells)
Bone marrow (produces other blood cells)

Question 16

secondary lympoid tissue

Answer 16

(mature immune cells interact with pathogen and initiate response)
Encapsulated:
Spleen
Macrophages encounter pathogens in the blood
Lymph node
Un-encapsulated (or diffuse lymphoid tissues)
Tonsils
Gut-associated lymphoid tissue (GALT)
Clusters of lymphoid tissues

Question 17

Name the three major classes of immune pathologies

Answer 17

Immunodeficiencies (under-reaction)
Primary immunodeficiency - more genetic
Acquired immunodeficiency (AIDS, HIV)
Allergy or hypersensitivity (over-reaction), immune system)
Autoimmune disease (mis-recognition)
E.g. type 1 diabetes, rheumatoid arthritis