Exercise immunology

Question 1

List some factors that may impair immune function, therefore, increasing susceptibility to illness?

Answer 1

exercise
psychological stress
poor diet
poor sleep

Question 2

What are some factors that increase pathogen exposure, therefore, increasing likelihood of illness?

Answer 2

travel (sleep disturbances)
travel (confined spaces)
crowding
improper hygiene
poor diet

Question 3

What are the 3 types of leukocyte in order of size?

Answer 3

> lymphocyte (smallest)
monocyte (mediumist)
granulocyte (largest)

Question 4

What are the 3 types of lymphocyte and how much of a reaction do they have to exercise (acute stress)?

Answer 4

B cells (small response)
T cells (medium)
NK cells (large)

Question 5

Describe how the lymphocyte cell count changes from pre-post to 10h post exercise

Answer 5

Pre - post: rises
post - 15 mins: drops to baseline
15 mins - 2hrs: falls below baseline
10hrs: returned to baseline

Question 6

Explain the process by which lymphocyte count rises and then drops post-exercise

Answer 6

> the adrenaline from exercise allows lymphocytes on vessel walls to change adhesion qualities, releasing them in to bloodstream (initial rise in lymphocyte count)
cells then leave bloodstream to travel to ‘at-risk’ tissues (fall in lymphocyte count)

Question 7

What are the two methods of sorting cells in humans?

Answer 7

1. count cells (coulter principle)

2. phenotype cells (flow cytometry)

Question 8

Describe the process of counting cells (coulter principle)

Answer 8

place whole blood in a machine which sorts leukocytes based on size

Question 9

Describe the process of phenotyping cells (flow cytometry)

Answer 9

place just the cells in a machine which can identify cells with specific proteins

Question 10

Describe the methods of Goebel & Mills’ research in 2000 into leukocyte expression following acute stress

Answer 10

observed NK cells and their gene expression through flow cytometry, both at rest and after a stressful task (exercise and public speech)

Question 11

Describe the findings of Goebel & Mills (2000)

Answer 11

> CD11a density increases w/ stress
CD62L density decreases w/ stress

so, CD62L being shed in response to stress, supported by greater conc of CD62L in blood plasma

Question 12

So CD62L are shed from NK cells in response to stress and end up in the blood plasma yeah?

Answer 12

not so fast boi,

Bosch et al (2005) found NO CHANGE in CD62L conc in blood plasma when changes in blood plasma volume was corrected for

Question 13

If CD62L density goes down with stress, but the conc in the plasma doesn’t increase,
WHAT THE SHIT is going on?

Answer 13

cytotoxic cells (lots of CD11a) increase in blood stream with stress because of the fight or flight response. they travel to tissues that are vulnerable (e.g. lungs, skin)
regulatory cells (lots of CD62L) don't have the same fight or flight response to stress.

Question 14

What are two broad confounders to immunology research?

Answer 14

1. cytomegalovirus

2. ppt fitness

Question 15

How many cytomegalovirus (CMV) affect immunology research?

Answer 15

CMV increases the immunological response, meaning that ppts with CMV may confound results if not controlled for

Question 16

How may individual fitness influence immunology research results?

Answer 16

less physically fit individuals have a MUCH greater T cell response to exercise and a slower recovery of T cell count post-exercise.
- (Hong et al, 2004)

Question 17

What is some research evidence linking psychological stress with susceptibility to inflammatory and infectious conditions?

Answer 17

Kiecolt-Glaser et al (2002)

Bosch et al (2002)

Cohen & Herbert (1996)

Question 18

The magnitude of NK cell mobilisation correlates with which other indicators of sympathetics nervous system activation?

Answer 18

> increased HR
increased BP
adrenaline secretion

therefore, NK cell mobilisation is an integrated component of fight or flight response

Question 19

How do NK cells protect against invading pathogens?

Answer 19

among the first immune cells to arrive at sites of tissue damage or infection
> have ability to immediately destroy infected cells
> release cytokines to attract other immune cells

• (Bosch et al, 2005)

Question 20

What function do regulatory NK cells perform?

Answer 20

regulatory NK cells have a immunomodulatory function through the secretion of cytokines

• (Bosch et al, 2005)

Question 21

What function do cytotoxic NK cells perform?

Answer 21

destroy infected cells

Question 22

Do immunoregulatory NK cells express high or low levels of the adhesion molecule CD62L?

Answer 22

regulatory = high CD62L

Question 23

Do cytotoxic NK cells express high or low levels of the adhesion molecule CD62L?

Answer 23

cytotoxic = low CD62L

Question 24

CD62L supports migration of lymphocytes to what location?

Answer 24

secondary lymphoid tissues
e.g. spleen, lymph nodes, tonsils

• (Bosch et al, 2005)

Question 25

CD11a supports migration of lymphocytes to what location?

Answer 25

the proximity of inflamed tissues

• (Bosch et al, 2005)

Question 26

Why is it useful for cells high in CD11a to travel to the inflamed tissue?

Answer 26

these cells (cytotoxic) can destroy the infected cells.

Question 27

Why does high cell-surface density of CD11a support the migration of lymphocytes to the inflamed tissue?

Answer 27

The ligands of CD11a (the molecules to which CD11a binds) are typically up-regulated on endothelial cells in the proximity of inflamed tissue

Question 28

Differentiate between leukocyte and lymphocyte

Answer 28

a lymphocyte is a type of leukocyte (wbc)

All lymphocytes are leukocytes but not all leukocytes are lymphocytes.