Microbiology Chapter 22.txt

• Naturally Acquired Active Immunity
• Artificially Acquired Active Immunity
• Naturally Acquired Passive Immunity
• Artificially Acquired Passive Immunity

Get the disease, then you are immune

Vaccine

• From mother
• IgA in colustrum
• IgG in while in the placenta
• Lasts about 6 months

• Given antibodies usually manufactured from horse serum, usually for Hepatitis A
• Lasts about 6 months

Cannot cause disease but you usually need boosters

Weakened virus. Has the possibility of disease but there is a better immune response

• It's getting easier to make these
• Put together a DNA sequence to create an epitope. The body codes an immune response.
• Really good

• Heat - DNA & Capsid
• UV Light - DNA

• Formaldehyde - DNA
• Metals - capsid
• Phenols - capsid
• Lipid solvents - damage to envelope

The best is to damage the DNA but not the capsid so you can get a good immune response but not the disease.

• Live, attenuated vaccines
• Inactivated vaccines
• Toxoid vaccines
• Subunit Vaccines
• Conjugate vaccines
• DNA vaccines

• Weakened microbes that multiply at only low levels, inducing a strong immune response
• Organisms can revert to a virulent form and cause disease

Combine vaccines for different diseases

Difficult and not widely used

• 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.

• Inactivated toxins (toxoids).
• Since the product is inactivated, booster shots are required.

Only those parts of the antigens that stimulate a strong immune response.

• Used to create recombinant subunit vaccines.
• Subunits cannot cause disease.

• Attaching bacterial capsule polysaccharides to a toxoid.
• They elicit a strong immune response
• HiB vaccine uses the virus capsule. Cooks the carbs and hooks to a toxiod.

• Take up and translate foreign DNA.
• Display the resulting proteins, inducing a strong immune response.

• Engineered plasmids that contain a gene from a pathogen.
• They are not infective or replicative, so cannot cause disease.

• 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).

Vaccine Adverse Events Reporting System (VAERS).

Should not take flu vaccinations.

Much greater than any risk associated with vaccines

• Make vaccines thick to slow down the bodies ability to destroy the antigen
• Gives a better immune response
• Witches brew of mineral oil, aluminum sulfate, cell walls of bacteria

• Precipitation
• Lattice formation
• Fluid precipitation
• Gel precipitation
• Diffusion and double diffusion
• Immunoelectrophoresis

• Requires the formation of a lattice between soluble antigen and antibody
• Something soluble in liquid
• Forms a lattice snowflake look
• The antigen is soluble
• Need about equal amounts of antigen and antibody to get this effect

• Fluid precipitation
• Gel precipitation
• Diffusion and double diffusion

• Looking for antibodies in the blood
• Use a known amount of antigen and keep diluting
• Hopefully there is so much antibody, eventually you get a 1 to 1 precipitation

Highest dilution that gives a positive result

• Used in determining titer
• If the line is close to Antigen, there are lots of Antibodies
• If the line is close to the Antibody, not good immunity to the disease

• A gel plate is cut to form a series of holes ("wells") in the gel.
• A sample is placed in one well, and sera or purified antibodies are placed in another well and the plate left for 48 hours to develop.
• During this time the antigens in the sample extract and the antibodies each diffuse out of their respective wells.
• Where the two diffusion fronts meet, if any of the antibodies recognize any of the antigens, they will bind to the antigens and form what is known as an immune complex. This immune complex precipitates in the gel to give a thin white line, which is a visual signature of antigen recognition.

• Is a general name for biochemical methods for separation and characterization of proteins based on electrophoresis and reaction with antibodies.
• In immunoelectrophoresis, diffusion is combined with electrophoresis.
• Pulls antigen based on charge
• Can separate out lots of antigens.

• On a gel-coated slide, an antigen is placed in a central well.
• An electrical current is run thru the gel to separate antigens by their electrical charge.
• A trough is made and a known solution of antibody is added.
• As antigens and antibodies diffuse toward one another through gel, precipitation lines are seen where optimal concentrations of antigens and antibodies meet.

Clumping when antibodies and antigen are mixed

• Antigens are absorbed onto latex beads.
• Antibodies are mixed in.
• Serum antibodies can be detected rapidly by observing agglutination of the carrier particle.

Red blood cells clumping

• Determine blood type.
• Detect viruses that cause agglutination of red blood cells.

Using antibodies that bind to the A or B blood group in a sample of blood.

• Used to detect the presence of either specific antibody or specific antigen in serum
• Used to diagnose infections, particularly with microbes that are not easily detected by culture methods, and in rheumatic diseases
• Superseded by ELISA and by DNA-based methods of pathogen detection, particularly PCR.
• Test serum - Heat to destroy complement
• Add known antigen & complement
• If serum is positive
• then Ag-Ab reaction uses up the complement
• Else
• complement is not used
• Add sheep RBC & anti-sheep Ab
• If complement exists
• Then lysys of sheep RBC
• If lysis then negative
• If no lysis then posistive

• Enzyme linked immunosorbent assay
• Requires a positive and a negative control. If either is wrong, throw out and start over

• Hook antigen onto latex bead
• Add test serum
• If Ab present then
• Attach to Ag
• Add Anti-Antibody
• If positive, the Anti-Antibody hooks to latex bead
• The Anti-Antibody has an attached enzyme (horseradish peroxidase)
• Add substrate � some type of colored protein
• Enzyme acts on substrate and will change color of substrate if positive

• For diagnosing syphilis
• Only looking for antibodies
• Similar to Eliza but instead of enzymes it uses fluorescence

• Ab made by plasma cells (working B cells)
• Fused to myeloma cells from a mouse
• The fusion results in a clone of hybridoma cells which are immortal and which produce a single type of antibody, the monoclonal antibody
• Can be used to produce Hep A Ab for those exposed.

• Method to produce multiple copies of DNA
• Have to have a primer: oligonucleotide
• Need 15-30 base pairs
• 1: DNA heated to separate the 2 strands (denature)
• 2: Cooled to allow primer oligonucleotides to hydrogen bond to each complementary strand
• 3: The DNA polymerase replicates the new strand by adding the appropriate complementary nucleotide
• 4: The cycle of heating, cooling and strand replication is repeated many times to produce millions of copies of the same double stranded DNA sequence.

Actively producing antibodies to an antigen.

The body's immune system responds to antigens by producing antibodies and lymphocytes.

Illness or pathogen exposure.

Vaccination.

• 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.

• 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

Difficult and not widely used

Combine vaccines for different diseases

• 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.

• Contain inactivated toxins (toxoids).
• Since the product is inactivated, booster shots are required.

• Contain only those parts of the antigens that stimulate a strong immune response.
• Subunits cannot cause disease.

Can be used to create recombinant subunit vaccines.

• Are created by attaching bacterial capsule polysaccharides to a toxoid.
• They elicit a strong immune response.

• Take up and translate foreign DNA.
• Display the resulting proteins, inducing a strong immune response.

• Contain engineered plasmids that contain a gene from a pathogen.
• They are not infective or replicative, so cannot cause disease.

• 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).

Also result by passively receiving antibodies to an antigen.

• Ccongenital immunity
• occurs when antibodies pass from mother to fetus.

3�6 months after birth

• First milk (colostrum).
• Breast milk.

• Injection of antibody-rich serum into a body.
• The serum can be used to:
• Prevent disease (prophylactic).
• Treat disease (therapeutic serum).

• As "nonself" and mount an allergic reaction.
• Immune complexes may form and serum sickness may develop.

• Effective vaccination programs
• The majority of a population are immune
• Unvaccinated individuals are unlikely to contact an infected individual.

• Population density
• The strength of a person's immune system

• Concentration of serum antibody that reacts to its antigen.
• A rise in the titer ratio (antibody:serum) indicates disease.