Chapter 11

Practical Applications of Immunology

Vaccine History

• Variolation: Inoculation of smallpox into skin (18th century).

• Vaccination: Inoculation of cowpox into skin.• Herd immunity results when most of a

population is immune to a disease.

Principal Vaccines Used in the United States to Prevent Bacterial Diseases in Humans

• DtaP

– Diphtheria: Purified diphtheria toxoid

– Pertussis: Acellular fragments of B. pertussis

– Tetanus: Purified tetanus toxoid

• Meningococcal meningitis: Purified polysaccharide from N.

meningitidis

• Haemophilus influenzae type b meningitis: Polysaccharides

conjugated with protein

• Pneumococcal conjugate vaccine: S. pneumoniae antigens

conjugated with protein

Principal Vaccines Used in the United States to Prevent Viral Diseases in Humans

• Smallpox: Live vaccinia virus

• Poliomyelitis: Inactivated virus

• Rabies: Inactivated virus

• Hepatitis A: Inactivated virus

• Influenza: Inactivated or attenuated virus

• Measles: Attenuated virus

• Mumps: Attenuated virus

• Rubella: Attenuated virus

• Chickenpox: Attenuated virus

• Hepatitis B: Antigenic fragments (recombinant vaccine)

Monoclonal Antibodies (Mabs)• Alemtuzumab: For leukemia• Infliximab: For Crohn’s disease• Rituximab: For non-Hodgkin’s lymphoma• Trastuzumab: Herceptin for breast cancer• Basiliximab and daclizumab: Block IL–2,

immunosuppresives for transplants• Palivizumab: Treatment of RSV

Monoclonal Antibodies

Figure 18.2

Monoclonal Antibodies• Immunotoxins: Mabs conjugated with a toxin to

target cancer cells.• Chimeric mabs: Genetically modified mice that

produce Ab with a human constant region.• Humanized mabs: Mabs that are mostly human,

except for mouse antigen-binding.• Fully human antibodies: Mabs produced from a

human gene on a mouse.

Precipitation Reactions

• Involve soluble antigens with antibodies.

Figure 18.4

Agglutination Reactions• Involve particulate

antigens and antibodies.

• Antigens may be

– On a cell (direct agglutination).

– Attached to latex spheres (indirect or passive agglutination).

Figure 18.5

Antibody Titer

• Is the concentration of antibodies against a particular antigen.

Figure 18.6

Viral Hemagglutination

• Hemagglutination involves agglutination of RBCs.

• Some viruses agglutinate RBCs in vitro.

Figure 18.8

Viral Hemagglutination-Inhibition• Hemagglutination involves agglutination of RBCs.• Some viruses agglutinate RBCs in vitro.• Antibodies prevent hemagglutination.

Figure 18.9b

Neutralization Reactions

• Eliminate the harmful effect of a virus or exotoxin.

Figure 18.9b

Complement Fixation Test

Figure 18.10 (1 of 2)

Complement Fixation Test

Figure 18.10 (2 of 2)

Fluorescent Antibody Techniques (Direct)

Figure 18.11a

Fluorescent Antibody Techniques (Indirect)

Figures 18.11b, 3.6b