Exercise and Cell-Mediated Immune Function Flashcards
What happens to rates of T-cell proliferation post exercise ?
Like the numbers this follows a biphasic response, However this is likely because there is a reduction in t-cells in circulation as seen with neutrophils.
If you look at this on an induvial cell basis the significant reduction is only seen following High intensity exercise, not in moderate.
How can different training backgrounds effects resting t-reg levels ?
Compared to sedentary people, recreationally active and sprint trained athletes, endurance athletes had significantly greater T-reg levels.
Moreover they also had greater expression of IL10 produced by T-regs indicating a lower general level in inflammation, but could lead to early damping of type 1 and type 2 cells during, leading to infection and illness.
Post exercise what is happening to T-regs (Turn off) cells ?
Similar to type 1 T-cells they are reduced post exercise and increased by 24h.
Are the following true or false ?
- Lymphocyte proliferative responses to acute exercise follow a biphasic pattern
- The effect of acute exercise on lymphocyte proliferation is independent of exercise intensity
- Flu and human rhinovirus are examples of mitogens
- In the 1- 4 hour(s) after exercise, proliferation per T cell decreases
- Some cells apoptose after exercise, this may account for some of the decrease in post-exercise T cell proliferation
- T cell proliferative responses are reported to increase in response regular training
- Lymphocyte proliferative responses to acute exercise follow a biphasic pattern - TRUE
- The effect of acute exercise on lymphocyte proliferation is independent of exercise intensity - FALSE
- Flu and human rhinovirus are examples of mitogens - FALSE
- In the 1- 4 hour(s) after exercise, proliferation per T cell decreases - TRUE
- Some cells apoptose after exercise, this may account for some of the decrease in post-exercise T cell proliferation - TRUE
- T cell proliferative responses are reported to increase in response regular training - TRUE
What are the names for increases and decreases in lymphocyte number and the causes of each ?
Increase - Lymphocytosis- adrenalin, demargination - Cells enter circulation.
Decrease - Lymphocytopenia - Cortisol - Cells go into tissues.
In the Kruger et al., 2008 student what did they show about the source of T-cells and their target locations following normal exercise in mice.
Source was the spleen
Target organs lung, bone marrow and Peyer’s Patches (Gut immune tissue).
T-cells migrate towards their target cell via chemotaxis. Following exercise what is the effect of this in control groups vs HRV infected condition ?
In the control group migration decrease to an equal point in both conditions, approximately 60%.
However by 1 hour post this has began to increase in the control condition, but in the infected condition it has dropped even further.
This indicated that there is something about the infection which reduced the migration capacity.
How do T cells respond to exercise ?
Both types (CD3/CD4 + CD3/CD8) undergo lymphocytosis and subsequent lymphocytopenia
Summary ??
- Total lymphocyte counts exhibit a biphasic response to exercise (adrenaline and cortisol mediated)
- T cell subsets during exercise and during recovery
Responses depend on intensity and duration
Subset increases (mobilisation) vary with adrenoreceptor density
Decreases most likely suggest the cells have entered the tissues - Mitogen-stimulated T cell proliferation also follows this pattern
Decreased function of each cell and/or role of apoptosis? - T cell migration is impaired after intense exercise
Cells are not able to move to where they are needed
Why do CD3/CD8 (Cytotoxic) T cells respond more to exercise than CD3/CD4 ?
This is because CD3/CD4 cells have a greater density of B2 adrenoreceptors of the surface, so are more responsive to adrenalin.
This is similar to NK cells but Not to as great of an extent.
What is the effect of regular training of T-cell proliferation.
Increases this.
How do Lymphocytes follow a biphasic response to acute exercise ?
Following exercise there is often an increase proportional to the intensity. And in recovery there is a significant decrease in numbers.
Is it just the number of IL2 cells (Type 1) that are decreased following exercise that effects immune function ?
No. The expression of IL2 by these cells is also reduced. This effect is significantly greater in trained participants.
This indicates that following exercise the reduction of IL2 , which is one cytokine which stimulates the anti-viral response is reduce, meaning there is a gap in immune function post exercise.
What was found by Steensberh et al., 2001 about the effect of intensive exercise of IL2 producing T-cells (type 1 helper/ type 1 cytotoxic) vs IL4 producing Type 2 T-cells ?
Immediately upon starting exercise there is an increase in the type 1 helper cells.
There is then the significant reduction following exercise and at 2 hours post, but by 24h is is returned to normal.
In the type 2 cells there was no significant difference in IL4 producing cells.
What did The reduction in t-cell proliferation mirror ?
Increase in apoptosis.
