Immunology

Question 1

Which leukocytes are granulocytes?

Answer 1

(Phils)

• Basophil
• Eosinophil
• Neutrophil

Question 2

What is the lifespan of each WBC?

Answer 2

• Granulocytes (4-8hrs in circulation, then 4-5 days in lining of blood vessels)
• Monocytes (10-20 hrs in circulation, months in tissues as macrophages)
• lymphocytes (weeks/months)

Question 3

What is the function of neutrophils and monocytes?

Answer 3

• innate immunity

- kill pathogen(bacteria)

Question 4

What is the function of Eosinophil?

Answer 4

• kill Parasites

Question 5

What is the function of Basophil?

Answer 5

• allergic reaction

Question 6

What is the function of lymphocytes?

Answer 6

• adaptive immune response

- trigger and produce antibodies

Question 7

What are the functions of tissue macrophages?

Answer 7

• engulf and lyse foreign cells/bacteria
• present pieces of bacteria to adaptive immune cells (T/B cells) to make antibodies and memory cells
• produce hydrogen peroxide and superoxide that are toxic to the bacteria
• activate the intake of antigen/antibody complex
• regulate Ca levels in the blood
• release growth factors for wound healing

Question 8

What are some of the chemotactic chemicals?

Answer 8

• chemotactic chemicals are chemicals that attract neutrophils and macrophages to the site of injury/attention.
• some ex. are bacterial toxins, complement cascade, activated clotting factors, prostaglandins/interleukins

Question 9

What is the most efficient leukocyte for phagocytosis?

Answer 9

• Macrophage is the most efficient as it can engulf up to 100 bacteria at a time and don’t die. They can also digest gram negative bacteria.
• Neutrophils are not efficient at all because they can only eat 5 bacteria at a time and die right after

Question 10

What is the difference between gram positive and gram negative bacteria?

Answer 10

• gram positive have thick peptidoglycan membrane and teichoic acid
• gram negative have lipopolysaccharide on their outer membrane
• LONG PPT

Question 11

What are the steps of phagocytosis?

Answer 11

1. microbe attach to phagocyte
2. bacteria is engulfed
3. engulfed bacteria forms phagosome(vesicle with bacteria)
4. lysosome and phagosome fusion (phagolysosome)
5. digestion/lysis of the bacteria
6. remaining indigestible material in vesicle
7. exocytosis of indigestible/waste material

Question 12

What are the different types of macrophages and where are they found?

Answer 12

• histiocytes: skin/sub-q
• tissue macrophages: lymphatic sinusoids
• alveolar macrophages: respiratory tract
• Kupffer cells: liver
• spleen macrophages: found in spleen, will digest circulating bacteria in spleen and immature/defective rbcs

Question 13

What is the function of reticuloendothelial system (RES)?

Answer 13

• infection prevention
• filtering function
• activating adaptive immune response

Question 14

What are the components of RES?

Answer 14

• circulating monocytes and tissue macrophages
• bone marrow
• spleen
• lymphatics

Question 15

What are some of the polysaccharide encapsulated bacteria and how does that affect phagocytosis?

Answer 15

• polysaccharide encapsulated bacteria have a thick polysaccharide capsule that prevents the bacteria from being phagosized by the phagocytes.
• ex. pneumococcus, meningococcus, H. flu