Your SlideShare is downloading. ×
Chap20 Immunology & Serology
Upcoming SlideShare
Loading in...5

Thanks for flagging this SlideShare!

Oops! An error has occurred.

Saving this for later? Get the SlideShare app to save on your phone or tablet. Read anywhere, anytime – even offline.
Text the download link to your phone
Standard text messaging rates apply

Chap20 Immunology & Serology


Published on

Published in: Technology, Health & Medicine
  • Be the first to comment

No Downloads
Total Views
On Slideshare
From Embeds
Number of Embeds
Embeds 0
No embeds

Report content
Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

No notes for slide


  • 1. Immunity and Serology Chapter 20
  • 2.
    • Immunity is a condition under which an individual is protected from the disease
    • Two general types of immunity
      • Innate Immunity
      • Acquired Immunity
    • Types of Acquired Immunity
        • Naturally Acquired Active Immunity
        • Artificially Acquired Active Immunity
        • Naturally Acquired Passive Immunity
        • Artificially Acquired Passive Immunity
    Immunity to Disease
  • 3. 4 Types of Acquired Immunity
  • 4.
    • Naturally acquired active immunity develops from exposure to an infectious agent
      • Active immunity occurs when the body’s immune system responds to antigens by producing antibodies and lymphocytes
      • Naturally acquired active immunity follows illness or pathogen exposure
    • Artificially acquired active immunity occurs through vaccination
      • Vaccines contain treated or altered microbes, toxins, or parts of microbes
        • a primary immune response occurs
        • memory cells are formed
        • the person does not usually become ill
    Active Immunity
  • 5.
    • Live, attenuated vaccines contain weakened microbes that multiply at only low levels, inducing a strong immune response
      • Organisms can revert to a virulent form and cause disease
      • A single-dose vaccine can combine vaccines for different diseases
      • Vaccines using attenuated bacteria are difficult and not widely used
    Types of Vaccines
  • 6.
    • Inactivated vaccines contain killed pathogens, which induce a weaker immune response
      • Booster shots are required to maintain immunity
      • They are safer than attenuated vaccines because they cannot cause disease
    • Toxoid vaccines contain inactivated toxins (toxoids)
      • Since the product is inactivated, booster shots are required
      • Prepared by incubating toxins with a chemical
    • *to avoid multiple injections, vaccines are combined into single-dose vaccine
    Types of Vaccines
  • 7.
    • Subunit vaccines contain only those parts of the antigens that stimulate a strong immune response
      • Recombinant DNA technology can be used to create recombinant subunit vaccines
      • Subunits cannot cause disease
    • Conjugate vaccines are created by attaching bacterial capsule polysaccharides to a toxoid
      • They elicit a strong immune response
    Types of Vaccines
  • 8.
    • DNA vaccines depend on the ability of some cells to:
        • take up and translate foreign DNA
        • display the resulting proteins, inducing a strong immune response
      • Naked DNA vaccines contain engineered plasmids that contain a gene from a pathogen
      • They are not infective or replicative, so cannot cause disease
    • Recombinant vector vaccines involve DNA incorporated into an attenuated pathogen
      • The pathogen:
        • takes the DNA into the cells (viral vector) or
        • incorporates the DNA and present antigens (bacterial vector)
    • *Adjuvants : increase efficacy of a vaccine or toxoid by increasing availability of the antigen in the lymphatic system. = stimulate phagocytic activity, IL 1 activation, sustained immune response
    Types of Vaccines
  • 9. Childhood and Adolescent Immunization Schedule - 2006
  • 10.
    • Passive Immunity develops when antibodies enter the body from outside source
    • Naturally acquired passive immunity (congenital immunity) occurs when antibodies pass from mother to fetus
      • Maternal IgG antibodies remain in the child 3-6 months after birth
      • Maternal antibodies also pass to the newborn through:
        • first milk (colostrum)
        • breast milk
    Passive Immunity
  • 11.
    • Artificially acquired passive immunity involves injection of antibody-rich serum into a body
      • The serum can be used to:
        • prevent disease (prophylactic)
        • treat disease (therapeutic serum)
      • Antiserum: hyperimmune serum or convalescent serum
    • The immune system may recognize foreign serum proteins as “nonself” and mount an allergic reaction
      • Immune complexes may form and serum sickness may develop
    Passive Immunity
  • 12.
    • In herd immunity, the majority of a population are immune
    • Unvaccinated individuals are unlikely to contact an infected individual
    • Herd immunity is affected by:
      • population density
      • the strength of a person’s immune system
    Herd Immunity
  • 13.
    • People with egg allergies should not take flu vaccinations
    • The risk of contracting a disease is much greater than any risk associated with vaccines
    • Thimerosal
    Do vaccines have dangerous side effects?
  • 14.
    • Serology: branch of immunology that studies serological reactions
    • Serological reactions can help diagnose microbial infections
    • Ag-Ab reactions are studied under laboratory conditions
    • Uses patient’s serum
    • Function: confirmatory test, detect organism in tissue, aid MD in following course of disease and determine immune states
    Serological Reactions
  • 15.
    • Titration is the dilution of antigen or antibody solution to the most favorable concentration
    • The titer is the most dilute concentration of serum antibody that reacts to its antigen
      • A rise in the titer ratio (antibody:serum) indicates disease
    Serological Reactions
  • 16.
    • Neutralization Involves Antigen-Antibody Reactions
      • Neutralization is used to identify toxins and antitoxins, viruses and viral antibodies
      • If a specific agent is suspected, to determine if the toxin has been neutralized, a sample can be:
        • mixed with an antitoxin
        • injected into a lab animal
        • Example: detection of botulinum toxin in food
      • The Schick test is used to determine if a person is immune to diphtheria (intradermal test)
    Serological Reactions
  • 17.
    • Precipitation reactions involve antigens and antibodies cross-linked in a huge lattice
    • In fluid, the molecules diffuse until they reach the ideal concentration (the zone of equivalence)
    • In immunodiffusion, antigens and antibodies diffuse through a gel until they reach the zone of equivalence
      • Oudin tube technique
      • Ouchterlony plate technique
    Serological Reactions
  • 18.
    • In immunoelectrophoresis, diffusion is combined with electrophoresis
    Serological Reactions
  • 19.
    • Agglutination – antibodies interact with antigens on a surface of a particular object and cause object to clump together.
    • A visible reaction requires less antibody or antigen if they are clumped together
    • In passive agglutination:
      • antigens are adsorbed onto a surface
      • antibodies are added
      • agglutination is observed
    Serological Reactions
  • 20.
    • Hemagglutination is used to:
      • determine blood type
      • Detect viruses that cause agglutination of red blood cells
    • Flocculation : precipitation and agglutination; Ag exists in a non-cellular particulate form that reacts with antibodies to yield large, visible aggregates.
    Serological Reactions
  • 21.
    • Complement Fixation Can Detect Antibodies to a Variety of Pathogens
    Serological Reactions
  • 22.
    • Labeling Methods Are Used to Detect Antigen-Antibody Binding
      • A fluorescent antibody technique can detect antigen-antibody binding by labeling antibodies with a fluorescent marker
      • Can be direct or indirect (FTA-ABS)
    Serological Reactions
  • 23.
    • The radioimmunoassay (RIA) is extremely sensitive, using radioactivity-labeled antigens; based on the competition between radioactive labeled Ag and unlabeled Ag for the reactive sites on Ab molecule
    • The radioallergosorbent test (RAST) uses radioactive antiglobulin antibodies
    Serological Reactions
  • 24.
    • The enzyme-linked immunosorbent assay (ELISA) is similar to RAST
      • It uses an enzyme system instead of radioactivity (horseradish peroxidase)
      • It is often used to detect antibodies against HIV
    Serological Reactions
  • 25.
    • Monoclonal Antibodies Are Becoming a “Magic Bullet” in Biomedicine
      • Polyclonal antibodies occur because there are multiple epitopes on a pathogen
        • They activate different B cell populations
  • 26.
    • In the lab, antibodies recognizing one epitope (monoclonal antibodies [mAb]) are produced using myelomas
    • Myeloma cells are fused to and activated B cell to form a hybridoma
    • A hybridoma producing the desired mAb can be cloned
    • MAbs can be used in:
      • disease prevention
      • immunomodulation (controlling overactive inflammatory responses)
  • 27.
    • Gene Probes Are Single-Stranded DNA segments
      • They hunt down complementary DNA fragment and emit a signal
      • The polymerase chain reaction (PCR) is used to increase the amount of DNA to be searched
      • Gene probes and PCR are use in:
        • HIV and HPV detection
        • water-quality tests