L2_ Intro to Immunology

Question 1

Briefly describe characteristics of the Innate Immune System (speed, variability, selectivity, dynamic)

Answer 1

Rapid Response (Hours), Fixed, Limited number of Specificities, Constant during response

Question 2

Briefly describe characteristics of the adapted immune system speed, variability, selectivity, dynamic)

Answer 2

Slow Response (days to weeks), variable, numerous highly selective specificities, improve during response

Question 3

What is one overriding similarity between Innate and Adaptive Immune responses?

Answer 3

They both have common effector mechanisms for the destruction of pathogens

Question 4

What is more important innate or adaptive immunity?

Answer 4

Innate! (without innate, we cannot even activate our adaptive)

Question 5

What is the largest organ involved in immunity?

Answer 5

Skin

Question 6

What are the 3 major mechanisms of the innate immune system?

Answer 6

Barriers, Phagocytes, Complement

Question 7

What is an Opsonin? List two types of particles that can be opsonins?

Answer 7

Something that increases the phagocytosis of an object by binding to the object. Complements and Antibodies

Question 8

List the 3 major mechanisms of Adaptive immunity

Answer 8

Antibody, T-cell Recognition, Cell Mediated Activation of the Innate Immune System.

Question 9

What is an antigen recognized by?

Answer 9

An Antibody or a T-Cell receptor

Question 10

Name the corresponding Tissue Macrophage for:

Liver, Skin, Connective Tissue, Brain, Bone, Joints, Lungs

Answer 10

Liver- Kupffer Cell, Skin-Histiocyte, Connective Tissue- Histiocyte, Brain-Microglial Cell, Bone-Osteoclasts, Joints-Synovial type A Cells, Lungs- Alveolar Macrophages

Question 11

What type of immunity is complement involved in?

Answer 11

Both Innate and Adaptive

Question 12

What is the most common opsonin of the complement system that can be recognized by many effector cell types?

Answer 12

C3

Question 13

Name the cell type, receptor, or ligand linked to the following CD groups: CD3, CD4, CD8, CD28, CD40, CD40L, CD25

Answer 13

CD3-Mature T-Cell
CD4-Helper T-Cell
CD8- Cytotoxic T-Cell
CD28- recognition of APC (B7)
CD40 - Co-stimulatory molecule
CD40L - Ligand for CD40
CD25 - IL-2 receptor (high affinity)

Question 14

What type of cell is a Neutrophil/polymorphonuclear leukocyte, What is their function, describe their life cycle.

Answer 14

They are a granulocyte and an end cell type. They phagocytize and kill microorganism. They have granules that contain the bactericidal and hydrolytic enzymes of the cell. They are short-lived once released from the bone marrow. They enter site of infection and die there and are taken up by macrophages.

Question 15

What is the most abundant leukocyte?

Answer 15

Neutrophils

Question 16

What is the main function of eosinophils, what is their abundance, how long do they remain in circulation, tissue?

Answer 16

They are granulocytes, they do not contain lysozyme but do contain eosinophilic basic protein(EBP) which is thought to be important in clearance of parasitic worms. 1-3% of leukocytes, removed from blood very quickly (T50 ~ 30min)

Question 17

What is the macrophage and dendritic cell precursor cell?

Answer 17

Monocyte

Question 18

Cytotoxic T-cells are known for mainly killing cells infected by what?

Answer 18

Virally infected cells

Question 19

Describe Natural killer Cells. What is their make up, and what are they known for doing?

Answer 19

They are large granular lymphocytes that are known to kill tumor cells and some virally infected cells without apparent specificity.

Question 20

Name the normal percentages for WBC differential: Neutrophils, Eosinophils, Basophils, Monocytes, Lymphocytes

Answer 20

Neutrophils 40-75%, Eosinophils 1-6%, Basophils <1%, Monocytes 2-10%, Lymphocytes 20-50%

Question 21

What are the three main (broad) functions of a T-Cell?

Answer 21

Help B-Cells, Stimulate phagocytes to kill better, and be directly cytotoxic to virally infected cells and tumor cells.

Question 22

What part of an antibody do effector cells bind?

Answer 22

The Fc region

Question 23

What two main targets can complement recognize?

Answer 23

Foreign microorganisms and also bound antibody molecules.

Question 24

Name the two major ways in which cells types are identified.

Answer 24

Morphological criteria- stains are used to view cells under a microscope
Antigenic- main monoclonal antibodies have been developed to recognize specific types of cells

Question 25

What types of cells do macrophages kill intracellularly and what types extracellularly?

Answer 25

Intracellular- bacteria, yeast, parasites

Extracellular- virally infected cells, larger parasites, tumor cells

Question 26

What is the function of dendritic cells?

Answer 26

Activation of T-cells and initiation of adaptive immune responses

Question 27

What are the functions of macrophages?

Answer 27

Phagocytosis and killing of microorganisms. Activation of T-Cells and initiation of immune responses

Question 28

What is the function of mast cells?

Answer 28

Expulsion of parasites from the body through release of granules containing histamine and other active agents

Question 29

What are the major targets of Cytotoxic T-Cells?

Answer 29

Virally infected cells.

Question 30

What are the primary immune organs?

Answer 30

organs where immature lymphocytes develop

Thymus and Bone Marrow

Question 31

What are the secondary immune organs?

Answer 31

tissues where antigen is localized so that it can be effectively exposed to mature lymphocytes
Lymph nodes, spleen, adenoids, peyers patches (GI tract)