L1 Intro to Immunology

Question 1

The study of immunology is…

Answer 1

the functioning of immune cells and system, includes the role of homeostasis, infectious and non-infectious pathogens. To control pathogens that enter the body (viruses, bacteria and parasites and cancers)

Question 2

Types of barriers to the entry of, or colonisation by pathogens

Answer 2

1. physical barriers: mucus, tight junctions of cells
2. chemical barriers: enzymes, pH
3. biological competition: if niche is already occupied, pathogens cannot easily move, there is always competition.

Question 3

Phagocytosis

Answer 3

the engulfing and destruction of foreign pathogens by neutrophils, macrophages and DC

Question 4

PAMPs
DC
NK

Answer 4

PAMPs: pathogen-associated molecular patterns
DC: dendritic cells
NK: natural killer cells

Question 5

What are phagocytes and their role?

Answer 5

these include macrophages, neutrophils and DC, and play a major role in the early response to pathogens

Question 6

Characteristics of neutrophils

Answer 6

• 60-70% of all leukocytes in humans: heavily abundant but short-lived for 1 day.
• FIRST CELL to migrate at site of infection/tissue damage
• most die at sit of infection –> makes up pus, release neutrophil NETS made of DNA strands to trap bacteria as their last “good deed”

Question 7

What are monocytes and macrophages?

Answer 7

Monocytes are the blood precursors to macrophages.

Macrophages reside in tissues, involved in phagocytosing pathogens, wound healing.

Question 8

Monocytes, macrophages and DC all release…

Answer 8

proteins that attract chemokines cells that activate cytokines.

Question 9

What is inflammation?

Answer 9

Body’s early response to infection, injury and any tissue damage.

Question 10

Why is inflammation needed?

Answer 10

it helps to attract and activate immune cells (phagocytes, other immune cells such as mast cells, natural killer cells, basophils, eosinophils) and get a PAMPs response to prevent infection and promote wound healing.

Question 11

What initiates inflammation?

Answer 11

Innate immune system (the internal defenses; immune cells) initiates inflammation.

Question 12

Why is PAMPs important?

Answer 12

it initiates inflammation caused by tissue damage and/or specific pathogen molecules.

Question 13

What are some responses to PAMPs?

Answer 13

1. secretion of cytokines and chemokines - enhanced inflammation
2. recognition of organisms for phagocytosis
3. Enhanced killing by phagocytes
4. maturation of DC, to activate T cells.

Question 14

Order the defense against infection

Answer 14

Firstly, it involves chemical and physical barriers –> then innate and acquired immune systems

Question 15

Innate response is …… rapid or slow?

does it have memory of previous infections?

Answer 15

Innate response is rapid and does not have memory of previous infections