Module 7 - Immunity Flashcards
Protection from infectious disease by a collective, coordinated response of the cells and molecules of the immune system
Immunology
Innate
-AKA Natural or native
-First line of defense
-Early, rapid
-Recognizes self vs. non-self, prevents establishment of infection
-Includes:
Skin, Mucous membranes, Phagocytic leukocytes, natural killer cells, plasma proteins (complements)
Adaptive
-AKA specific or acquired
-Second line of defense
-Slower, more effective
-Recognition, plan, attack
Two types of responses:
-Humoral: B lymphocytes antibodies
-Cell-mediated: T lymphocytes activate phagocytes or kill host cells
Antibodies
IgG (most abundant - crosses placenta) IgA IgM (first circulating Ig to appear in response to an antigen and it the first antibody type made by a newborn) IgD IgE
Adaptive: Humoral
- Defend in blood and mucous
- B lymphocytes produce antibodies
- B cells recognize antigen –> into plasma cells, then secrete antibodies
- Antibodies bind to microbes before they invade tissue and mark microbe for destruction
Adaptive: Cell-Mediated
- Inside the cell where antibodies can’t get to
- T lymphocytes recognize APC
- Helper T Cells: Help out B cells w/ antibody production and phagocytes destroy their contents
- Cytotoxic T Cells: Kill intracellular microbes
Factors Affecting Immune Response
- Age (Newborn/Elderly)
- Nutritional Status (Malnutrition, Excess Adipose Tissue - chronic inflam response)
- Stress
Rapid reaction to exposure to antigen, can be within minutes, range in severity from rhinitis to anaphylaxis
Immediate Hypersensitivity (IgE 0
Inflammatory response that takes 24-72 hours to develop in response to activated mononuclear lymphocytes; exemplified by the tuberculin skin test
Delayed (Type IV) Hypersensitivity
Life-threatening hypersensitivity manifested by widespread edema, bronchospasms, and vascular shock secondary to vasodilation (histamines)
Systemic Anaphylaxis
- previous exposure to antigen creates IgE
- Level of severity dependent on level of sensitization to antigen
Symptoms of Anaphylaxis
Hives, itching, difficulty breathing, vomiting, cramps, diarrhea, edema, and obstruction of the airway
Common Antigens in Systemic Anaphylaxis
Food
Insects
Drugs
Latex
_____ are potent vasodilators that respond to antigen exposure within 5-30 minutes, increasing capillary permeability and smooth muscle contraction and bronchoconstriction
Histamines
___________ block histamine release and treat symptoms such as edema, rhinitis, hives, etc.
Antihistamines
ex. Benadryl, Claritin, Zyrtec
- caution pt about drowsiness
- Breakdown in the body’s ability to differentiate b/w self and non-self antigens
- Specific cause is unknown, could be genetic and/or environmental (includes infectious agents)
Autoimmune Disorders
-can affect almost any type of cell or tissue in the body
Treatments of Autoimmune Disorders
Immunosuppressive agents
Steroids
Work by preventing DNA synthesis in immune cells, preventing replication and eventually causing cell death
Immunosuppresive Agents
- Works by suppressing inflammatory response that characterizes disorders such as rheumatoid arthritis and lupus
- Can have severe side effects depending on dosage and length of therapy
Steroids
Primary Immunodeficincies
- Congenital/inherited
- Etiology: Genetic (recessive, X-linked or autosomal mutations)
- Patho: mutations affect signaling pathways that dictate immune cell development/symptoms of A.I disorders
- Clinical consequences: early detection is critical, types of infection help diagnose, family trees are important, can be fatal in early childhood
Secondary Immunodeficincies
- Acquired (AIDS is the most common)
- Etiology: pathogen, aging, malignancies, malnutrition, drugs
- Patho: IgG loss, T cell deficit, wbc dysfunction
- Clinical consequences: no cure, immunosuppressed, congenital transmission is possible
HIV develops into Acquired Immune Deficiency Syndrome in the presence of a CD4 count below ___ and /or an ______ ______
below 200
opportunistic infection
HIV is transmitted through ____, _____, _____ ____, _____
Sexual contact is the most common method
Blood
Semen
Vaginal Fluid
Breastmilk
HIV is a _______ that infects certain cells (CD4 T Cells, macrophages, dendritic cells)
The death of these types of cells create decreased immune response even if the person is asymptomatic, creating susceptibility to many illnesses
Retrovirus
Stages of HIV
- Primary Infection
- Latency (Chronic, asymptomatic)
- AIDS (HIV, CD4 below 200 +/ opportunistic infection)
Antiretrovirals
- Decrease the amount of virus in the body
- 5 classes: each class attempts to interrupt the life cycle of the virus at different points
Combination therapy is ideal, usually at least 3 drugs called:
HAART
Highly Active AntiRetroviral Therapy
Goal is undetectable viral load and increasing CD4 count
