Chapter 17: Immunization and Immune Testing

**Describe how antibodies are acquired for passive immunotherapy.

clinicians remove blood cells and clotting factors from the blood of donors(humans or large animals); the result is serum, which contains a variety of antibodies, particularly gamma globulins

**titer

in serology, a measure of the level of antibody in blood serum, determined by titration and expressed as a ratio reflecting the dilution

**Describe the three major safety concerns or problems with vaccines.

mild toxicity, risk of anaphylactic shock, and residual virulence from attenuated viruses

**variolation

"or inoculation was the method first used to immunize an individual against smallpox (Variola) with material taken from a patient or a recently variolated individual in the hope that a mild, but protective infection would result"(Wikipedia.com)

**Describe the difference between active vs passive immunity.

Active immunity is the administration of "antigens" to actively mount an immune response(vaccination or natural exposure), and passive immunity is the transfer of "antibodies" formed by an immune individual or animal where the individual acquires immunity(maternal transfer of an antibody or serum immunity).

**Describe where scientists got the term vaccination.

Cowpox was also called vaccinia and that is how Jenner came to name the technique "vaccination" and the protective inoculum a vaccine.

**Describe the difference between the four types of antibody tests.

Fluorescent-use fluorescent dyes as labels; when exposed to a specific wavelength of light the fluorescent dye glows Direct-fluorescent-used to identify the presence of antigen in a tissue; to identify small numbers of bacteria in patient tissues Indirect fluorescent-used to detect the presence of specific antibodies in an individuals serum via a 3 step process. Used to detect antibodies against many viral, protozoan, or bacterial pathogens, and used to identify and separate types of WBC's. ELISAs-used to detect the presence and quantify the abundance of antibodies in serum, where the label is an enzyme that reacts with its substrate to produce a colored product that indicates a positive test; has 5 basic steps

**Describe Edward Jenner's 1796 experiment and its key finding.

Jenner took crusts from a person infected with cowpox and proved that protection from the disease could be done through inoculation(the introduction of a pathogen or antigen into a living organism to stimulate the production of antibodies).

**Describe the three major limitations of passive immunotherapy.

Repeated injections of animal-derived antisera can trigger an allergic response called serum sickness, in which the recipient mounts an immune response against animal antigens found in the antisera The patient may degrade the antibodies relatively quickly; therefore protection is not long lasting The body does not produce memory B cells in response to passive immunotherapy, so the patient is not protected against subsequent infections

**Describe and identify the purpose of labeled antibody tests.

a different form of serological testing that involve antibody molecules that are linked to some molecular "label" that enables them to be detected easily. Labels include radioactive chemicals, fluorescent dyes, and enzymes. Used to detect either antigens or antibodies

**Identify the purpose of a Western blot test and briefly describe how it is performed.

a technique used to detect a specific protein, such as an antibody, in a complex mixture; used to confirm the presence of proteins, including antibodies against pathogens. It involves 3 steps: 1) Electrophoresis- antigen solutions are placed into wells and separated by gel electrophoresis producing invisible protein bands 2) Blotting-protein bands are transferred onto blotting paper and cut into strips 3)Antibody testing-each strip is incubated with a test solution, washed, enzyme-labeled antibody solution is added, then washed again, exposed to the enzymes substrate, color develops wherever antibodies against the proteins in the test solutions have bound to their substrates

**vaccination

active immunization; specifically against smallpox

**immunization.

administration of an antigenic inoculum to stimulate an adaptive immune response and immunological memory

**Describe passive immunotherapy.

administration of antiserum that contains preformed antibodies, it provides immediate protection against a recent infection or ongoing disease because it does not require the body to mount a response, instead, pre-formed antibodies are immediately available to bind to antigen, enabling neutralization and opsonization to proceed without delay.

**agglutination

aggregation(clumping) caused when antibodies bind to 2 antigens, perhaps hindering the activity of pathogenic microorganisms and increasing the chance that they will be phagocytized

**Identify the pros and cons and the difference between the following types of vaccines: attenuated vaccines, inactivated vaccines, toxoid vaccines, combination vaccines, and vaccines using recombinant gene technology.

attenuated vaccines: pros-use pathogens with reduced virulence, active microbes stimulate a strong immune response, can provide contact immunity; cons-can result in mild infections, modified microbes may retain enough residual virulence to cause disease in susceptible individuals inactivated vaccines: pros-safer than live vaccines, cons-often require multiple doses to achieve full immunity, chemicals added to increase effective antigenicity toxoid vaccines: pros-useful for some bacterial diseases, stimulate antibody-mediated immunity; cons-require multiple doses because toxoids possess few antigen determinants combination vaccines: pros- "minimize the number of injections children receive, reducing the cost of stocking and administering separate vaccines, facilitating the addition of new vaccines into immunization programs; cons-chemical incompatibility or immunologic interference when different antigens are combined into one vaccine could be difficult to overcome"(CDC.gov). vaccines using recombinant gene technology-"pros-can be used to improve vaccines, produce large quantities of very pure antigens for use in vaccines; cons-low levels, not as protective as live vaccine, potential for reversion"(ncfar.org).

**Describe the difference between acquired and natural immunity.

natural is not produced by immune response(The placental transfer of IgG from mother to fetus during pregnancy) Acquired immunity is gained after birth as a result of the immune response( exposure to an infectious agent or other antigens by the body. The body responds by making its own antibodies).

**hemagglutination

reaction when the particles agglutinated are RBC's

**Explain whether current research supports the claims that vaccines can trigger autism, diabetes and/or asthma.

research has not substantiated these allegations

**Be able to combine these four concepts correctly and provide examples of each.

see above

**titration

serial dilution of blood serum to test for agglutination activity

**vaccine

the inoculum used in active immunization

**Describe herd immunity and its purpose. Explain what is used in the U.S. to enable herd immunity.

the resistance of pathogens by a large portion of individuals(typically more than 75%) via means of following an immunization schedule recommended by the CDC.

**Describe and identify the purpose of agglutination tests.

these tests involve the clumping of antigenic particles by antibodies. The purpose of these tests is to determine blood types in humans and to determine the concentration of antibodies in a clinical sample.