I&d Ageing And The Immune System

Front 1

What ailments are older people typically more susceptible to?

Back 1

Respiratory tract infections
Invasive Staphylococcus aureus infections
Tetanus
Poor response to influenza vaccination

Front 2

The gradual deterioration of the immune system brought on by natural age advancement

Back 2

Immunosenescence

Front 3

Define 'immunosenescence'

Back 3

The gradual deterioration of the immune system brought on by natural age advancement

Front 4

Age-associated decline in immunity is associated with adaptive, but not innate immunity T/F

Back 4

False! It affects both

Front 5

What changes occur in the primary lymphoid organs and tissues with ageing? (2)

Back 5

Haematopoiesis
Thymus involutes (To become involute; curl up)

Front 6

There is no effect to the number of prigenitor cells produced in the bone marrow with age T/F

Back 6

F, the numbers decrease

Front 7

When does the thymus start involuting?

Back 7

After puberty

Front 8

What is the effect of thymic involution?

Back 8

There is decreasing output of mature T-cells

Front 9

PRRs are heavily affected by ageing T/F

Back 9

False. Many are not at all.

Front 10

When does adaptive immunity peak?

Back 10

Puberty

Front 11

When does innate immunity peak?

Back 11

Birth

Front 12

What are the age-associated changes of the innate immune system?

Back 12

Aged macrophages and neutrophils have an imapired respiratory birst and reactive nitrogen intermediates as a result of altered intracellular signalling

Aged neutrophils are less able to respond to rescue from apoptosis

NK cells are less cytotoxic and make less IFN-gamma

NKT (NK T-cells) increase in number and produce more IL-4 with age

Levels of complement components are altered with advancing age

Front 13

The innate immune system, with age, can contribute to alterations in acquired immunity. What are these alterations?

Back 13

DC and macrophage interaction with T and B cells becomes less effective, and they are less likely to stimulate them

Front 14

Changes with age to:
Neutrophils

Back 14

Decrease in reactive oxygen species

Increased apoptosis

Front 15

Changes with age to:
Dendritic cells

Back 15

Decreased T and B cell stimulation

Decreased number of plasmacytoid (Of or pertaining to plasma cells) DCs

Front 16

Changes with age to:
Macrophages

Back 16

Decrease in reactive oxygen species

Decrease in reactive nitrogen intermediates

Increase in prostaglandin E2

Decrease in interleukin-6

Front 17

What does prostaglandin E2 do? Why is this flashcard here?

Back 17

Important effects in labour (softens cervix and causes uterine contraction) and also stimulates osteoblasts to release factors that stimulate bone resorption by osteoclasts

Prostaglandin E2 increases in aged macrophages

Front 18

Important effects in labour (softens cervix and causes uterine contraction) and also stimulates osteoblasts to release factors that stimulate bone resorption by osteoclasts

Back 18

Prostaglandin E2

Front 19

A pro-inflammatory and anti-inflammatory cytokine. It is secreted by T cells and macrophages to stimulate immune response to trauma, especially burns or other tissue damage leading to inflammation

Back 19

Interleukin-6

Front 20

What does interleukin-6 do? Why is this flashcard here?

Back 20

a pro-inflammatory and anti-inflammatory cytokine. It is secreted by T cells and macrophages to stimulate immune response to trauma, especially burns or other tissue damage leading to inflammation

IL-6 production is decreased by aged macrophages

Front 21

Changes with age to:
NK cels

Back 21

Increase number of NK cells

Decreased cytotoxicity

Front 22

Changes with age to:
Natural killer T cells

Back 22

Increased numbers of NKT cells

Front 23

NK cells decrease with age T/F

Back 23

False, they increase

Front 24

The number of T-cells remains relatively constant throughout life, however, a type of T cell does decrease. What type?

Back 24

Naive T-cells number declines (however, counteracted to an extent by the expansion of memory T cells)

Front 25

Why are infrequent T-cell memory cells lost with age?

Back 25

There is an accumulation of T cells specific for antigens that are continuously present, which overcrowds the memory T-cell pool, and the constriction leads to loss of infrequent memory T-cell populations

Front 26

Why are elderly people likely to lose immunity to diseases they were previously immune to?

Back 26

Due to overcrowding of the T-cell pool, loss of infrequent T cell populations (e.g. influenza and VZV) can be lost

Front 27

Defects in T-cell receptor signaling

Alterations in cytokine production (decreased IL2 and IFN-gamma)

Loss of proliferative capacity

Loss of cytotoxic T helper functions

Back 27

Processes behind age-related immune dysfunction

Front 28

During ageing, the T-cell surface can become remodeled, leading to loss which co-signaling molecules?

Rich's age

Back 28

CD27 and CD28

Up-regulation of inhibitory NK and T-cell receptors

Front 29

Is the rate at which age related changes can occur more pronounced in CD4+ or CD8+ cells? Why is this?

Back 29

CD8+ (CD4+ have greater homeostatic stability)

Front 30

What is the ultimate limit for the number of divisions that a human lymphocyte can undergo?

Back 30

The telomere length

Front 31

What is the randem hexanucleotide repeat of a human chromosome's telomere?

Back 31

TTAGGG (10-15 kb long!)

Front 32

Because telomeres are essential for maintaining chromosomal integrity, cells with critically shortened telomeres...

Back 32

...cease division and are prone to apoptosis

Front 33

Which enzyme synthesises telomeres?

Back 33

Telomerase

Front 34

During ageing, T-cells display shorter telomeres but more telomerase activity T/F

Back 34

False! Shorter telomeres AND less telomerase activity

Front 35

Amount of antibody in the circulation decreases quite significantly during ageing T/F

Back 35

F

Front 36

What are the changes in the quality of antibody response due to ageing?

Back 36

Decrease in antibody affinity

Diminished ability to produce antibodies to vaccines

Change in isotype of antibody responses (e.g. young IgG1 for flue, old IgG3 for flu)

Hypermutation impaired

Increase in autoantibody ( an antibody (a type of protein) manufactured by the immune system that is directed against one or more of the individual's own proteins) production

Front 37

What is an autoantibody?

Back 37

An antibody (a type of protein) manufactured by the immune system that is directed against one or more of the individual's own proteins

Front 38

An antibody (a type of protein) manufactured by the immune system that is directed against one or more of the individual's own proteins

Back 38

Autoantibody

Front 39

Which autoantibodies are produced in higher quantities due to ageing?

Back 39

Rheumatoid factor, ant-dsDNA, antihistones and anticardiolipin antibodies.

Front 40

Which CDs can lead to dysfunctionalco-stimulation of Th-cells?

Back 40

CD28-B7 and CD40L-CD40 interactions

Front 41

There is some evidence for a decrease in IgE mediated allergies with age, and an increase in salivary igG and IgA levels. Perhaps reflecting changes in mucosal immunity

Back 41

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