Characteristics of innate immune cells

Question 1

What are the cells of the innate immune system?

Answer 1

Neutrophils
Eosinoophils
basophils

Question 2

What are characteristics of neutrophils?

Answer 2

Neutrophils phagocytose the microbes and kill them intracellularly

do not antigen present

Question 3

What do the primary or azurophilic granules of nuetrophils contain?

Answer 3

myeloperoxidase enzyme,
lysozyme
α-defensins

Question 4

What do the secondary granules of nuetrophils contain?

Answer 4

alpha lactoferrin

Question 5

What is the function of myeloperoxidase and lysosomes?

Answer 5

myeloperoxidase - catalyze the formation of hypochlorous acid and oxygen singlet

lysozyme - degrades peptidoglycan

Question 6

What are characteristics of eosinophils?

Answer 6

EosInophils have bilobed nucleus
Eosinophils have basic granules in cytoplasm
Protection against parasitic infections.
Contain basic proteins

Question 7

What are the basic proteins of eosinophils?

Answer 7

major basic protein (MBP)
eosinophil cationic protein (ECP)
eosinophilic derived neurotoxin (EDN)
eosinophil peroxidase (EPO)

Question 8

What are the characteristics of basophils?

Answer 8

found in low numbers in blood
type I hypersensitivity response
act much like mast cells (found in tissues)

Question 9

What are characteristics of monocytes?

Answer 9

Monocytes are major phagocytic cells and provide first line defense against intracellular pathogens
Monocytes are precursors of macrophages
Macrophages have a long life span ranging from months to years
Macrophages are named differently according to the organs in which they differentiate

Question 10

What are the pathways that monocytes/macrophages kill microorganism?

Answer 10

generation of reactive oxygen intermediates
reactive nitrogen intermediates, antimicrobial peptides
by fusion of phagosomes containing bacteria with lysosomes
Antimicrobial peptides
They express CD14 on their cell surface

Question 11

What are characteristics of dendritic cells?

Answer 11

Most efficient antigen presenting cells

Capable of both phagocytosis and pinocytosis

Question 12

What are characteristics of natural killer cells?

Answer 12

NK cells express activating receptors (KAR) and killer inhibitory receptors (KIR) on their cell surface
NK cells recognize abnormal cells that express low levels of MHC class I molecules
NK cells produces perforin and granulysin that can kill the target cells