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Immunization---What are the 4 types of Vaccines?
- 1. Whole Cell vaccines -LIVE,
- *adv. LIFE TIME IMMUNITY
- *disadv. NOT for immune compromised patients.
- *EX --- measles, mumps, rebella.
- 2. Inactivated whole-agent
- *disadv. NEED booster
- *EX --- rabies, polio, influenza
- 3. Subunits
- *Adv. CANT produce in patients.
- 4. Conjugated vaccines --- strictly use Polysacharrides as antigen.
- *Disadv. NO MEMORY CELLS
- *can by pass this obstacle by binding to a carrier protein to produce MEMORY CELLS.
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Factors Affecting Longevity
- 1. nature of the antigen used
- *most lasting - ATTENUATED, LIVE
- 2. Vaccine Boosters, increase time
- 3. Route of administration
- *Oral, Nasal aerosol
- 4. Proper storage of vaccines
- *LIVE vaccines is most important to have proper storage.
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Hypersensitivity Reactions = allergy
TYPE I
TYPE II
TYPE III
TYPE IV
- Type I (Anaphylactic): - antigens combine with IgE antibodies - can be systemic or localized -
- *ex: shock associated with venom, hay fever, asthma
- Type II (cytotoxic): - involves IgG and IgM AND complement destruction of
- host cells -
- *ex: transfusion reactions, Rh incompatabilit
- Type III (Immune complex): - antigen-antibody complexes deposited in tissues - cause an inflammatory response -
- *ex: arthus reactions, serum sickness
- Type IV (delayed hypersensitivity):
- - antigens activate TC (cytotoxic) cells - Tc cells kill host cells -
- *ex: transplant rejections, contact dermatitis
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Mechanism of Type I: Sensitization steps and Hypersensitivity
- Sensitization: --> Dendritic Cells bind to a pollen (antigen) - present the antigen to T helper 2 cell with MHC2. - T cell then clone itself to produce MEMORY T helper 2 cell, and at the same time call for help from B cell. - B cell then clone itself for MEMORY B cell at the same time makes PLASMA cells to produce adjacent IgE antibodies. (later will bind to mast cells or basophils in order to recognize antigen)
- Hypersensitivity --> When pollen antigen is bind to adjacent antibodies of mast cell or basophil, degranualation occur, where histamine and other mediators are released.
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Localized Anaphylaxis
- Allergens associated with FOOD and POLLEN
- *Daily allergy.
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Systematic Anaphylaxis
AKA. Anaphylatic shock
*associate with venoms --- MECHANISM?
- mediators --- cause peripheral blood vessels to expand = sudden drop in blood pressure --- SHOCK
- *Treatment --- Epinepherine Pen to contrict blood vessels.
- *prevention --- Desensitization = increase IgG instead of IgE. Repeatedly expose to increasing dosage of denatured antigen. effective with animal venoms.
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Type II. CYTOTOXIC REACTION
- *Antibodies IgG & IgM
- *Complement gets activated as a result of anitbodies binding to the antigen. ---causing cell lysis and damge.
- *EX--- Immune complex, but no cytotoxic,
- Most common --- blood transfusion, HEMOLYTIC disease = Rh - mother and Rh+ fetus
- ---> can be prevented by determining the patient's blood type as well as Rh
- *5 - 10 hrs symptoms occur
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Hemolytic disease
- Mother is Rh -, when carrying a baby that is Rh +, when breaks in placenta, the antigen from Rh + baby enters the mother's body, making her body produce Anti Rh anitbodies. When the mother is pregnant the second time, the baby with a positive Rh will attract the anti Rh antibody from the mother and lead to attack of the fetus red blood cells.
- *Prevent sensitization by administering the mother with Anthi Rh first,
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TYPE III (immune complex) hypersensitivity
- antigen binds to antibodies don't get destroyed, but rather attach to host tissue, causing an intense immune response = inflammation of tissue. Tissue destruction often occur
- *Arthus Reaction --- Local, injection of antigen with a patient that has a large amount of IgG to antigen; EDEMA and HEMORRHAGING = DEAD tissue.
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Type IV (Cell mediated) Hypersensitivity Reaction
- *This reaction only deals with T helper cells only. NO ANTIBODY
- *takes about 12 hrs+
- *EX Poison IVY - dermatitis; TB, indication.
- *In this reaction, Sensitized T helper 1 bind to PRESENTING cell, secrete Cytokines to attract Macrophages and initial inflammation action tissue damage.
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Systemic Lupus Erythematosus
- *IgG, IgM, IgA antibodies are produced against patient's DNA --- during normal cellular death process. immune complexes deposited in skin, joints, CNS. etc.
- *occur more frequently in women, butterfly rash on the face.
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4 types of Transplant
- 1. Autocraft --- own tissue
- 2. isocraft --- identical twin's
- 3. Allocraft --- Other's tissue
- 4. xenocraft --- animal tissues
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