Psychoneuroimmunology

Question 1

What does PNI stand for?

Answer 1

psychoneuroimmunology

Question 2

Give some examples of how psychological stress can affect immunity indirectly?

Answer 2

• Smoking
• Obesity
• Lack of exercise
• Poorer medication compliance
• Alcohol and drug use
• Risky sexual practices
• Poor sleep
• Caffeine

Question 3

PNI is the study of ways in which stress ________ affects immunity.

Answer 3

directly

Question 4

Stress directly affects immunity due to alterations in __________ mechanisms that contribute to disease or infection

Answer 4

homeostatic

Note: The idea that all stress is just “bad” for immunity is oversimplified… It’s more like “maladaptive under certain circumstances”

Question 5

How innate immunity works

Answer 5

Question 6

T/F The Autonomonic nervous system sends nerves into tissues that form or store the cells of the immune system and eventually enter the circulation

Answer 6

True

Question 7

T/F Immune System tissue has receptors for all the interesting hormones released by the pituitary (HPA Axis) under the control of the brain

Answer 7

True

Question 8

What is conditioned immunosuppression?

Answer 8

1. Give an animal a drug that suppresses the immune system along with an artificially flavored drink (the conditioned stimulus)
2. Immune function is suppressed
3. A few days later present the artificially flavord drink by itself
4. Immune function is suppressed!

Question 9

What is the significance of conditioned immunosuppression?

Answer 9

Conditioned immunosuppression is the paradigm which was used in the study which most solidified the link between the brain and the immune system

Question 10

What are the two kinds of immunity?

Answer 10

1. Acquired
2. Innate

Question 11

Acquired Immunity involves monocytes (macrophages) which enlist the assistance of lymphocytes (T cells and B cells) in two different types of responses to the presence of an infecious agent.

1. T-Cells bring about _____________ immunity
2. B-Cells bring about ________________ immunity

Answer 11

1. T-Cells bring about cell-mediated immunity.
2. B-Cells bring about antibody-mediated immunity.

Question 12

The cascade of cell-mediated immunity involves four steps:

1. An __________ _____ is encountered by a type of monocyte called a ___________.
2. This stimulates the __________ to present the __________ _____ to a _ ______ ____ and to release __________-_ which stimulates _ ______ ____ activity
3. The _ ______ ____, as a result, releases __________-_ which triggers _ ____ proliferation.
4. This eventually causes another type of white blood cell, _________ ______ _____, to proliferate and destroy the infectious agent.

Answer 12

1. An infectious agent** is encountered by a type of monocyte called a **macrophage.
2. This stimulates the macrophage** to present the **infectious agent to a T helper cell** and to release **interlukin-1 which stimulates T helper cell activity
3. The T helper cell**, as a result, releases **interlukin-2 which triggers T cell proliferation.
4. This eventually causes another type of white blood cell, cytotoxic killer cells, to proliferate and destroy the infectious agent.

Question 13

The cascade of antibody-mediated immunity also involves four steps:

1. An __________ _____ is encountered by a type of monocyte called a ___________.
2. This stimulates the __________ to present the __________ _____ to a _ ______ ____ and to release __________-_ which stimulates _ ______ ____ activity
3. The _ ______ ____, as a result, releases _-____ ______ ______ which triggers differentiation and proliferation of another white blood cell _-_____.
4. The _-_____ make and release specific __________ that bind to surface proteins of the __________ _____, targeting it for destruction.

Answer 13

1. An infectious agent** is encountered by a type of monocyte called a **macrophage.
2. This stimulates the macrophage** to present the **infectious agent** to a **T helper cell** and to release **interleukin-1** which stimulates **T helper cell activity
3. The T helper cell**, as a result, releases **B-cell** **growth factor** which triggers differentiation and proliferation of another white blood cell **B-cells.
4. The B-cells** make and release specific **antibodies** that bind to surface proteins of the **infectious agent, targeting it for destruction.

Question 14

In order to sound immune alarms throughout this far-flung system, blood borne chemical messengers that communicate between different cell types, called _________ have evolved

Answer 14

Cytokines

Examples of cytokines include interleukin-1 and interleukin-2

Question 15

Acquired Immunity has three features:

1. The ability to specifically ______ a pathogen with antibodies and cell-mediated immunity that specifically _________ that pathogen.
2. I takes ____ to build up that immunity when you are first exposed to a pathogen.
3. ________ ________ to a pathogen will boost those defenses even further

Answer 15

1. target (imagine a bullet with pathogen-X’s name on it)
2. time (this involves finding which antibody has the best fit and generating a zillion copies of it)
3. repeated** **exposure (continues to boost targeted immunity further)

Question 16

Innate immunity is a ___________ immune response which tends to occur at the beachhead where a pathogen gets its first foodhold, like your skin, or moist mucosal tissue in your mouth or nose.

Answer 16

nonspecific

These types of antibodies generically attack any sort of microbe they encounter (i.e. saliva)

These types of antibodies are secreted and coat your mucosal surfaces like an antiseptic paint.

Question 17

One example of innate immunity is a type of response that occurs at the site of an infection causing inflammation. This happens in three stages:

1. tissue injury accompanied by bacteria triggers the release of ________ _______ such as _________
2. blood vessels respond with increased dilation and leakiness allowing cells of the innate immune response such as __________ and _____ to slip out of the circulation to infiltrate the immediate area of infection
3. __________ such as ___________ and __________ along with ______ ______ _____ consume the bacteria and cell debris, followed by healing.

Answer 17

1. tissue injury accompanied by bacteria triggers the release of chemical signals** such as **histamine
2. blood vessels respond with increased dilation and leakiness allowing cells of the innate immune response such as phagocytes** and **fluid to slip out of the circulation to infiltrate the immediate area of infection
3. Phagocytes** such as **macrophages** and **neutrophils** along with **natural killer cells consume the bacteria and cell debris, followed by healing.

Question 18

The best documented way in which stress-induced immunosuppression occurs is via _______________.

Answer 18

Glucocorticoids

Question 19

Which are affected more by the effects of glucocorticoids, B-cells or T-Cells?

As a consequence which type of immunity is more disrupted antibody-mediated immunity or cell-mediated immunity?

Answer 19

T-cells and cell-mediated immunity is most disrupted by the effects of glucocorticoids.

Question 20

T/F stress causes the active expenditure of energy in order to disasemble the preexisting immune system

Answer 20

True

Question 21

Under some circumstances the immune system will ask the body to secrete hormones that will ultimately suppress the immune system, how does this happen?

1. The immune system releases the cytokine (aka chemical messenger) __________-_
2. __________-_ stimulates the hypothalamus to release ___
3. ___ stimulates the pituitary gland to release ____
4. ____ causes the adrenal release of _____________
5. _____________ in turn suppress the immune system

Answer 21

1. The immune system releases the cytokine (aka chemical messenger) interleukin-1
2. interleukin-1** stimulates the hypothalamus to release **CRH
3. CRH** stimulates the pituitary gland to release **ACTH
4. ACTH** causes the adrenal release of **glucorticoids
5. glucorticoids in turn suppress the immune system

Question 22

T/F up to about the first thirty minutes after the onset of a stressor many aspects of immune response is enhanced?

Answer 22

True

This is true for all realms of immunity, but in particular for innate immunity.

Question 23

T/F by about an hour after the onset of a stressor sustained glucorcorticoid and sympathetic activation begins to have the opposite effect, namely, suppressing immunity

Answer 23

True

Question 24

T/F It is only with major stressors of longer duration, or with really major exposure to glucocorticorticoids, that the immune system does not just return to baseline, but plummets into a range that really does qualify as immunosuppressing

Answer 24

True

Question 25

Immune function varies across time in which ways as they relate to which three phases of stress

Answer 25

1. *Onset* of Stress - Immune function *spikes* 2. *Moderately prolonged* stress- Immune function *returns to baseline* 3. *Chronic* Stress - Immune function *plummets below baseline into the immunospuressive range*

Question 26

When a persons immune system remains on heightened alert and fails to return to baseline after moderately prolonged stress immune function can rise into the __________ \_\_\_\_\_\_\_ \_\_\_\_\_

Answer 26

**autoimmune disease range**

Question 27

T/F glucocorticoids prevent immune system response to stress from spiraling into the autoimmune range

Answer 27

**True**

Question 28

While glucocorticoids are know to suppress immune function in massive doses, they can *subtly enhance immune function* in which two ways? 1. A subtle rise in glucocorticoid levels for a short time (like in phase B) and the hormones only kill _____ \_\_\_\_\_\_\_\_\_\_\_ which don't work as well, thereby _________ the immune response. 2. Glucorcorticoids and epipinephrine divert ___________ from circulation and ________ them to the front lines.

Answer 28

1. A subtle rise in glucocorticoid levels for a short time (like in phase B) and the hormones only kill **_older_ _lymphocytes_** which don't work as well, thereby **_sculpting_** the immune response. 2. Glucorcorticoids and epipinephrine divert **_lymphocytes**_ from circulation and _**reassign_** them to the front lines.

Question 29

Sapolsky describes two paradoxical facts about autoimmunity, glucocorticoids and stress: 1. large doses of glucocorticoids make autoimmune diseases ____ \_\_\_\_\_\_\_\_ 2. at the same time stress can ______ autoimmune diseases

Answer 29

1. large doses of glucocorticoids make autoimmune diseases **_less_ _damaging_** 2. at the same time stress can **_worsen_** autoimmune diseases

Question 30

Links between stress and disease can follow two routes _________________ and \_\_\_\_\_\_\_\_\_

Answer 30

**psychoneuroimmune** and **lifestyle**

Question 31

The psychoneuroimmune route between stress and disease follows four stages defined by changes in

Answer 31

1. **level of stress** 2. **glucorcorticoid levels** 3. **immune function** 4. **disease resistance**

Question 32

The lifestyle route between stress and disease follows twp stages defined by changes in

Answer 32

1. **stress level** 2. **treatment compliance, rates of protective and risk factors**

Question 33

Sapolsky tests the four step psychoneuroimmune route model attempting to explain the known relationship between social support (or alternatively isolation) and it's impact on various diseases. what does he find for each stage?

Answer 33

1. social isolation is a stressor 2. little evidence for or against chronically over-reactive stress response 3. social isolation dampens some aspect of immune function 4. mixed results instudies attempting to prove increase in socially isolated stress caused the disease Overall pretty good case can be made that soical isolation can impact health through the effects of stress on immunity

Question 34

Sapolsky tests the four step psychoneuroimmune route model attempting to explain the known relationship between stress and the common cold. what does he find?

Answer 34

More stress equaled about three times the likelihood of succumbing to a cold after being exposed to the rhinovirus (common cold). Prolonged stressors more than a month long that were social in nature provided the greatest risk.

Question 35

Sapolsky tests the four step psychoneuroimmune route model attempting to exploring the relationsip between stress and worsening aspects of AIDS. what does he find?

Answer 35

psychoneuroimmune aspects could contribute to a link between stress and worsening aspects of AIDS more research is needed to examine how much stress influences whether people comply with their treatment regimes vs. how well their treatment regimes work.

Question 36

T/F Herpes DNA contains a strand of DNA that is sensitive to glucocorticoid levels, and when levels are up, that DNA sensor activates the genes involved in coming out of latency.

Answer 36

**True**

Question 37

T/F Herpes can trigger neurosystem response further imparing and exploiting your immune system after coming out of latency

Answer 37

**True** ## Footnote Herpes can cause your hypothalamus to release CRH which releases ACTH which raises glucocorticoid levels which suppress the immune system further while impairing your immune defenses against activated herpes.

Question 38

T/F Stress increases the risk of cancer

Answer 38

**False**

Question 39

T/F Stress increases risk of relapse out of remission from cancer

Answer 39

**False**