UNDERSTANDING STRESS AND DISEASE CHAPTER 6

The Immune System The system responsible for recognizing SELF from NON-SELF. The system responsible for recognizing SELF from NON-SELF. Solely responsible for killing 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) Works 24/7. You are never not bombarded with things that are NOT SELF (Sorry germ phobics)

Those That Are Not Self 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 Lymph Nodes Bean-shaped spongy tissue Largest are in the neck, arm- pit, abdomen, and groan Filters to capture antigens (foreign material) and has compartments for lymphocytes. Lymph vessels Connects to lymph nodes and carries fluid called lymph into the blood stream

Immune System Units Leukocytes White Blood Cells Macrophages Granulocyte Lymphocytes Produced by bone marrow T Cells B Cells

TYPES OF IMMUNE RESPONSES Innate Immunity invariant (generalized) early, limited specificity the first line of defense Also called Nonspecific Barriers 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 Acute inflammation in initiated by a stimulus such as injury or infection. Acute inflammation in initiated by a stimulus such as injury or infection. Inflammatory mediators are produced at the site of the stimulus. CYTOKINES Inflammatory mediators are produced at the site of the stimulus. CYTOKINES This increases pain too This increases pain too Blood vessels dilate and increase permeability Blood vessels dilate and increase permeability Attract phagocytes to the site of inflammation and activate them. Attract phagocytes to the site of inflammation and activate them. These cells then eat or destroy invaders These cells then eat or destroy invaders

Specific Response: T and B Cells

Cell-Mediated Immunity T cells recognize foreign antigens on the surface of cells, organisms, or tissues: Helper T cells – Present things Cytotoxic T cells – Kill things Suppressor T cells – Turn off T cells regulate proliferation and activity of other cells of the immune system: B cells, macrophages, etc. Defense against: Bacteria, fungi and viruses that are inside host cells and are inaccessible to antibodies. Cancer cells

Humoral Immunity 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 IMMUNE DEFICEINCY IMMUNE DEFICEINCY HIV/AIDS HIV/AIDS CANCER? – IMMUNE SURVEILLENCE THEORY CANCER? – IMMUNE SURVEILLENCE THEORY AUTOIMMUNE DISORDERS AUTOIMMUNE DISORDERS ALLERGIES ALLERGIES

Autoimmune Disorders Organ-specific Multiple Sclerosis Type I Diabetes Hashimoto’s Thyroiditis Systemic Systemic Lupus Erythematosus Rheumatoid arthritis

Gender and Immune Function Women respond to antigens more strongly than men Estrogen may affect the development or function of immune cells May explain why more women develop autoimmune diseases

PSYCHONEUROIMMUNOLOGY STRESS STRESS IMMUNE FUNCTION IMMUNE FUNCTION DISEASE DISEASE THE STUDY OF HOW THESE INTERACT

PNI: From stressor to illness We differ as to the pattern and frequency of stressors to which we are exposed 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 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) The magnitude and frequency of the stress response regulate immune competence (e.g., via glucocorticoids) Level of immune competence determines susceptibility to disease Level of immune competence determines susceptibility to disease

PSYCHONEUROIMMUNOLOGY STRESS IMPAIRS IMMUNE FUNCTION STRESS IMPAIRS IMMUNE FUNCTION DIRECT – SYMPATHETIC NS & HORMONES DIRECT – SYMPATHETIC NS & HORMONES Cohen et al. (2007) – Being unemployed reduced natural killer cell cytotoxicity. Getting a job recovers function Cohen et al. (2007) – Being unemployed reduced natural killer cell cytotoxicity. Getting a job recovers function INDIRECT – LIFESTYLE/COPING INDIRECT – LIFESTYLE/COPING IMPAIRED IMMUNE FUNCTION CAN CAUSE DISEASE IMPAIRED IMMUNE FUNCTION CAN CAUSE DISEASE

Cohen et al. (2007)

Direct and Indirect Paths EVENT RESPONSE APPRAISAL IMMUNE SUPPRESSION LIFESTYLE DISEASE

STRESS AND DISEASE HEADACHES HEADACHES INFECTIONS INFECTIONS CARDIOVASCULAR DISEASE CARDIOVASCULAR DISEASE DIABETES DIABETES RHEUMATOID ARTHRITIS RHEUMATOID ARTHRITIS

THE DISPOSITION FACTOR DIATHESIS-STRESS MODEL DIATHESIS-STRESS MODEL GENETIC FACTORS GENETIC FACTORS PHYSICAL PHYSICAL PSYCHOLOGICAL PSYCHOLOGICAL EXPOSURE EXPOSURE DEVELOPMENTAL DEVELOPMENTAL PERSONALITY PERSONALITY Hardiness Hardiness Optimism Optimism

Personality Factors: Hardiness Hardiness Hardiness Cluster of stress-buffering traits consisting of commitment, challenge, control 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 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 Hardy people are more likely to engage in positive reappraisal of stressful events

Personality: Optimism and Immune Functioning (Segerstrom et al. 1998) Examined law students over the course of the first semester of LS. Examined law students over the course of the first semester of LS. Took measures (T1 & T2) of dispositional and situational optimism & pessimism Took measures (T1 & T2) of dispositional and situational optimism & pessimism Drew blood at T1 & T2 to measure numerous immune parameters. 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