Exam 1: Cells of the Immune System

Question 1

Define Hematopoiesis

Answer 1

Physiological mechanism to produce RBC, WBC, and platelets

Question 2

3 major lineages for hematopoiesis

Answer 2

1. Erythroid - erythrocytes and platelets
2. Myeloid - granulocytes, mast cells, monocytes, macrophages, myeloid dendritic cells
3. Lymphoid - Lymphocytes (T and B cells)

Question 3

Hematopoietic Growth Factors

Answer 3

1. Colony stimulating factors (CSF) - granulocyte-monocyte CSF, Granulocyte CSF
2. Interleukins (IL) - IL1, IL3, IL4, IL5, IL6, IL7

Question 4

Neutrophils: description and location

Answer 4

First line of defense

Polymorphic nucleus - segmented, can have different shapes

Granular cytoplasm

Location: blood

Bird neutrophil is called heterophil

Question 5

Eosinophils: Description and location

Answer 5

Eosinophilic granules - stain red with eosin

Location: blood and tissues lining gastrointestinal tract and airways

Question 6

Monocytes: description and location

Answer 6

Second line of defense against pathogens

Important role in chronic infection

Large roundish nucleus

Diffuse pale blue-grey staining cytoplasm commonly containing vacuoles

Location: blood

Question 7

Mast Cells: description and location

Answer 7

When mast cells activated - contents of granules released and induce inflammation

Round nucleus, cytoplasm densely packed with granules (purple)

Location: tissues - particularly connective tissue surrounding vasculature and nerves, lamina propria of mucosa

Question 8

NK Cells: Description and location

Answer 8

Large lymphoid cell, round nucleus, azurophilic cytoplasm granules

Location: blood, spleen

Question 9

Lymphocytes

Answer 9

Capable of specifically recognizing and distinguishing different antigens

Adaptive immune response, specificity, and memory

Question 10

B cells (6 things)

Answer 10

Recognize extracellular antigens

Produce antibodies

Differentiate in plasma cells

Main role in humoral immune response

Mature in Bone marrow

In birds mature in the Bursa of fabricius

Question 11

T cells (6 things)

Answer 11

Recognize intracellular antigens

Do not produce antibodies

Differentiate in several types of lymphocytes

Main role in cellular immune response

Mature in Thymus

Produce cytokines

Question 12

Neutrophils: classification and lineage

Answer 12

Classification: granulocyte, phagocyte

Myeloid lineage

Question 13

Neutrophils: Function

Answer 13

Antimicrobial effectors - particularly in acute bacterial infection

Question 14

Neutrophils: Mechanism of action

Answer 14

Phagocytosis, degranulation, neutrophil extracellular trap formation

Question 15

Eosinophils: Classification and lineage

Answer 15

Classification: granulocyte

Myeloid lineage

Question 16

Eosinophils: Function

Answer 16

Anti-parasitic effectors - particularly in helminthic infection, some antiviral action, roles in allergy

Question 17

Eosinophils: Mechanism of action

Answer 17

Degranulation, limited phagocytosis

Question 18

Basophils: Description and location

Answer 18

Blue-purple basophilic granules with basic dyes

Location: blood

Question 19

Basophils: Classification and lineage

Answer 19

Classification: granulocyte

Myeloid lineage

Question 20

Basophils: function

Answer 20

Mediator of inflammation

Question 21

Basophils: Mechanism of action

Answer 21

Degranulation

Question 22

Monocytes: Classification and lineage

Answer 22

Classification: mononuclear phagocytes

Myeloid lineage

Question 23

Monocytes: Function

Answer 23

Precursors of macrophages and DCs

Question 24

Monocytes: Mechanism of action

Answer 24

Limited antimicrobial function in blood

Question 25

Macrophages: Description and location

Answer 25

Round nucleus, clear-vacuolated cytoplasm, irregular cell shape Location: peripheral tissue

Question 26

Macrophages: Classification and lineage

Answer 26

Classification: mononuclear phagocyte, sentinel cell, antigen presenting cell Myeloid lineage

Question 27

Macrophages: Function

Answer 27

Immune surveillance, moderate antimicrobial capacity, limited antigen presentation

Question 28

Macrophages: Mechanism of action

Answer 28

Detection of threats and release of inflammatory mediators, phagocytosis

Question 29

Dendritic cells: Description and location

Answer 29

Professional antigen presenting cells Round nucleus, clear cytoplasm, irregular shape with long branched projections (dendrites) Location: tissues

Question 30

Dendritic cells: Classification and lineage

Answer 30

Classification: mononuclear phagocyte, sentinel cell, antigen presenting cells Myeloid lineage

Question 31

Dendritic cells: Function

Answer 31

Immune surveillance, antigen processing and presentation

Question 32

Dendritic cells: Mechanism of action

Answer 32

Detection of threats and release of inflammatory mediators, endocytosis and phagocytosis

Question 33

Mast cells: Classification and lineage

Answer 33

Classification: sentinel cells Myeloid lineage

Question 34

Mast cells: Function

Answer 34

Immune surveillance, mediator and amplifier of inflammation and allergy

Question 35

Mast cells: Mechanism of action

Answer 35

Detection of threats and release of inflammatory mediators via degranulation (vasoactive amines) or synthesis of lipid mediators and cytokines

Question 36

NK cells: Classification and lineage

Answer 36

Classification: lymphocyte Lymphoid lineage

Question 37

NK cells: Function

Answer 37

Destruction of virally infected or abnormal host cells (including tumor cells)

Question 38

NK cells: Mechanism of action

Answer 38

Recognition of virally infected cells or abnormal host cells and target release of cytotoxic granules