Immune Response Immunization Characteristics of Acquired Immunity Recognition

Immune Response Immunization

Characteristics of Acquired Immunity Recognition of non-self Antigenic specificity Memory

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Naturally Acquired Active Immunity The body responds to antigens that enter naturally, such as during infections.

Naturally Acquired Passive Immunity Antibodies are transferred from mother to offspring, either across the placenta (Ig. G) or in breast milk (Ig. A).

Artificially Acquired Active Immunity Healthcare workers introduce antigens in vaccines; the body responds with humoral immune responses

Artificially Acquired Passive Immunity Healthcare workers introduce preformed antibodies (obtained from immune individuals) as antisera and antitoxins into a patient.

Immune Serum Globulin (ISG), aka Gamma Globulin • • • Contains immunoglobulin extracted from the pooled blood of at least 1, 000 human donors Processing concentrates the antibodies to increase potency and eliminates potential pathogens Method of choice for preventing measles and hepatitis A and in replacing antibodies in immunodeficient patients • Injected intramuscularly • Protection lasts 2 -3 months

Antisera and Antitoxins of Animal Origin Can be used when a human immune globulin is not available Example: sera produced in horses for diphtheria, botulism, and spider and snake bites

Vaccination Vaccination: exposing a person to material that is antigenic but not pathogenic Stimulate a primary and secondary anamnestic response to prime the immune system for future exposure to a virulent pathogen Two types of Vaccines Inactivated Attenuated

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Principles of Vaccine Preparation

Genetically Engineered Vaccines • • Recombinant DNA technology Trojan horse vaccine – Genetic material from an infectious agent is inserted into a live carrier microbe that is nonpathogenic – The recombinant microbe multiplies and expresses the foreign genes – The vaccine recipient will be immunized against the microbial antigens • DNA vaccines

Route of Administration and Side Effects of Vaccines • • • Most vaccines are injected by subcutaneous, intramuscular, or intradermal routes Only a few oral vaccines available, even though they have advantages Some vaccines required the addition of an adjuvant Common side effects – Local reactions at the injection site – Fever – Allergies Some patients experience reactions to the medium rather than the antigens

To Vaccinate: Why, Whom, and When? Not only confers protection to the individual receiving the vaccine, but it also protects public heath Herd immunity ◦ Collective immunity through mass immunization confers indirect protection on the nonimmune members ◦ Important force in preventing epidemics

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