Transcript Understanding Stress and Disease

UNDERSTANDING
STRESS AND DISEASE
CHAPTER 6
The Immune System
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The system responsible for recognizing SELF
from NON-SELF.
Solely responsible for killing NON-SELF
Works 24/7. You are never not bombarded
with things that are NOT SELF (Sorry germ
phobics)
Those That Are Not Self
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Antigen - any substance that
can trigger an immune
response. Some are
pathogens.
Bacterial – microorganisms
in the environment. Grow
rapidly and compete with our
cells for nutrients.
Fungi – organisms like mold
and yeast. Absorbs nutrients.
Viruses – proteins and
nucleic acid. Take over cell
and generate their own
genetic instructions.
Immune System Structure
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Lymph Nodes
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Bean-shaped spongy tissue
Largest are in the neck, armpit, abdomen, and groan
Filters to capture antigens
(foreign material) and has
compartments for
lymphocytes.
Lymph vessels
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Connects to lymph nodes and
carries fluid called lymph into
the blood stream
Immune System Units
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Leukocytes
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White Blood Cells
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Macrophages
Granulocyte
Lymphocytes
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Produced by bone
marrow
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T Cells
B Cells
TYPES OF IMMUNE RESPONSES
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Innate Immunity
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invariant (generalized)
early, limited specificity
the first line of defense
Also called Nonspecific
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Barriers
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Skin
Tears
Macrophages
Granulocytes
Mast Cells
 Adaptive Immunity
 variable (custom)
 later, highly specific
 ‘‘remembers’’ infection
 Also called Specific
 T cells – Cell mediated
 B cells - Humoral
Nonspecific Response: Inflammation
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Acute inflammation in initiated
by a stimulus such as injury or
infection.
Inflammatory mediators are
produced at the site of the
stimulus. CYTOKINES
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This increases pain too
Blood vessels dilate and increase
permeability
Attract phagocytes to the site of
inflammation and activate them.
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These cells then eat or destroy
invaders
Specific Response: T and B Cells
Cell-Mediated Immunity
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T cells recognize foreign
antigens on the surface of cells,
organisms, or tissues:
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Helper T cells – Present things
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Cytotoxic T cells – Kill things
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Suppressor T cells – Turn off
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T cells regulate proliferation and
activity of other cells of the
immune system: B cells,
macrophages, etc.
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Defense against:
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Bacteria, fungi and viruses that
are inside host cells and are
inaccessible to antibodies.
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Cancer cells
Humoral Immunity
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Antibodies are produced by
B cells.
B cells are stimulated and
actively secrete antibodies
These cells are called
plasma cells.
Antibodies are found in
extracellular fluids (blood
plasma, lymph, mucus, etc.)
and the surface of B cells.
Defense against bacteria,
bacterial toxins, and viruses
that circulate freely in body
fluids, before they enter
cells.
Immunological Memory
Overview of Immune Response
Overview of the Immune
Response
IMMUNE DISORDERS
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IMMUNE DEFICEINCY
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HIV/AIDS
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CANCER? – IMMUNE SURVEILLENCE THEORY
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AUTOIMMUNE DISORDERS
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ALLERGIES
Autoimmune Disorders
•Organ-specific
•Multiple Sclerosis
• Type I Diabetes
•Hashimoto’s Thyroiditis
•Systemic
•Systemic Lupus
Erythematosus
•Rheumatoid arthritis
Gender and Immune Function
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Women respond to antigens more
strongly than men
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Estrogen may affect the
development or function of
immune cells
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May explain why more women
develop autoimmune diseases
PSYCHONEUROIMMUNOLOGY
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STRESS
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IMMUNE FUNCTION
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DISEASE
THE STUDY OF HOW THESE INTERACT
PNI: From stressor to illness
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We differ as to the pattern and frequency of stressors to
which we are exposed
These variations determine the magnitude and
frequency with which we turn on the stress-response
The magnitude and frequency of the stress response
regulate immune competence (e.g., via glucocorticoids)
Level of immune competence determines susceptibility
to disease
PSYCHONEUROIMMUNOLOGY
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STRESS IMPAIRS IMMUNE FUNCTION
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DIRECT – SYMPATHETIC NS & HORMONES
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Cohen et al. (2007) – Being unemployed reduced natural
killer cell cytotoxicity. Getting a job recovers function
INDIRECT – LIFESTYLE/COPING
IMPAIRED IMMUNE FUNCTION CAN
CAUSE DISEASE
Cohen et al. (2007)
Direct and Indirect Paths
EVENT
DISEASE
APPRAISAL
IMMUNE
SUPPRESSION
RESPONSE
LIFESTYLE
STRESS AND DISEASE
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HEADACHES
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INFECTIONS
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CARDIOVASCULAR
DISEASE
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DIABETES
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RHEUMATOID
ARTHRITIS
THE DISPOSITION FACTOR
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DIATHESIS-STRESS MODEL
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GENETIC FACTORS
PHYSICAL
 PSYCHOLOGICAL
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EXPOSURE
 DEVELOPMENTAL
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PERSONALITY
Hardiness
 Optimism
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Personality Factors: Hardiness
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Hardiness
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Cluster of stress-buffering traits
consisting
of commitment, challenge, control
Linked to lower levels of anxiety,
adaptive coping styles, and
adjustment to cancer,
cardiovascular disease, diabetes, and
many other health problems
Hardy people are more likely to
engage in positive reappraisal of
stressful events
Personality: Optimism and Immune
Functioning (Segerstrom et al. 1998)
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Examined law students
over the course of the first
semester of LS.
Took measures (T1 & T2)
of dispositional and
situational optimism &
pessimism
Drew blood at T1 & T2 to
measure numerous immune
parameters.
PUTTING IT ALL TOGETHER
AGENT
Germ
Tobacco
HOST
Diathesis
Hardiness
Appraisal
ENVIRONMENT
Life Events
Hassles
Social Support
Exposure Risk
DISEASE