Immunity Flashcards Preview

Principles of Medicine > Immunity > Flashcards

Flashcards in Immunity Deck (24):
1

3 things that the body can recognise for viruses

Capsid shape
Inflamed cells
Infected cells

2

3 things that the body can recognise for bacteria and fungi

Surface antigens
Metabolites
Damaged cells

3

3 things that the body can recognise for parasites

Shape
Damaged cells
Life cycle changes

4

4 types of barrier to infection

Physical e.g. skin
Microbial e.g. bacteria balance
Humoral e.g. inflammation
Cellular e.g. B and T lymphocytes

5

3 things neutrophils recognise

Common bacterial cell wall components
C3b complement component
Fc region of antibodies

6

Role of lymphatic system

Fluid from blood leaks out of capillaries into surrounding tissues via hydrostatic pressure
Tissue damage enhances fluid movement and tissue swelling
Lymphatic system collects this fluid from extracellular tissue spaces and drains it through a thin walled tree like vessel system by normal muscle activity in the body mediated by valves that direct the flow in one direction

7

Primary lymphoid organs

Red bone marrow
Thymus

8

Secondary lymphoid organs

Adenoids
Tonsils
Spleen
Peyers patches
Lymph nodes
Thoracic ducts
Lymphatic vessels
Appendix

9

Biochemical surface defence mechanisms

Lysozyme
Sebaceous gland secretions
Commensal organisms in gut and vagina
Spermine in sperm

10

Biophysical surface defence mechanisms

Mucus
Respiratory cilia
Stomach acid
Skin

11

Dendritic cells

Carry infection through lymphatics to lymph node and recruit antigen specific cells

12

Process of foreign antigens meeting the immune system

1) Antigen uptake by Langerhans cells (dendritic cells in skin and mucosa)
2) Langerhans cells elave skin and enter lymphatic system
3) Langerhans cells enter lymph node and become dendritic cells
4) Dendritic cells present antigen on surface
5) T cells in lymph node cluster around dendritic cell
6) T cells with receptors specific to antigen presented become stimulated

13

Immunological tolerance

Mechanism of the body to avoid autoimmunity

14

Effector lymphocytes

B lymphocytes
CD8 T lymphocytes
K cells
NK cells

15

Regulator lymphocytes

CD4 T lymphocytes
Helper T cells
Regulatory T cells

16

Non-specific immunity

Recognition of characteristic common to many substances

17

Specific immunity

Recognition of unique or uncommon characteristic of particular foreign substance

18

3 ways that shape recognition is accomplished

Non-specific immunity
Specific immunity
Recognition of common substance in uncommon context

19

B lymphocytes can recognise:

A wide range of antigenic substances

20

T lymphocytes can recognise:

Short peptide antigens typically between 8 and 20 amino acids long

21

Epitope

Part of antigen recognised by receptor
Can be high, medium or low affinity due to finite number of lymphocytes - not all epitopes can have high affinity because the specificity required means we wouldn't have enough lymphocytes to generate a response against many things

22

B cell differentiation

Antigen presents to surface immunoglobulin receptor on B cell
CD79 signal transduction molecule activated
Internal signal generated
B cell differentiates into antibody forming cell

23

T cell differentiated

Antigen presents to T Cell Receptor (TCR)
CD3 signal transduction molecule generates internal signal
T cell differentiates into cytotoxic or helper T cell

24

Antibody structure

Protein with 4 polypeptide chains
2 heavy and 2 light chains in covalently bonded structure
Ends of light and heavy chains (ends of the Y) are variable
Middle of the Y is constant region
Hinge region produces arms of Y
Complement binding region on tail of Y - activates complement cascade
Epitope of antigen fits into middle of Y arms
Interchain and intrachain disulphide bonds present
Fab (arms of Y) and Fc (tail of Y) regions