Optimal temperature: 40-45°C

Above 60°C = proteins will start to deature

Agglutination - within minutes

Precipitation - Hours to days

- Initial binding of a single antibody to a single antigen

- tests are difficult, complex and expensive

- basic antigen/ antibody reactions are taken a further step, forming cross links or lattice formation to create large molecules that are easily detectable

The initial force of attraction that an antibody for a specific antigenic epitope or determinant

The sum of all attractive forces between an antigen and an antibody

involves combination of soluble antibody with soluble antigen to produce insoluble complexes

- Zone of excess of antibodies

- Instead of forming cross- link, the antibody coat the antigen vecause of little amount of antigen

- Zone of excess of antigen

- Instead of forming cross- link, they occupy the paratope

= A soluble antigen + antibody will create insoluble complexes

= more complexes are present = more turbid

= measures the turbidimetry or cloudiness of a solution by detection of light refracted by the sample

= soluble antigen + antibody = insoluble complexes

= precipitation techniques that use gel instead of a liquid as the medium

= Aragose gel usually used

= simplest immunodiffusion test

= oudin method

= If the antibody present reacts with the added antigen a precipitin band will form in the gel

= Fahey (kinetic method) and Mancini (end point method)

= Radial immunodiffusion method

= Used for quantitation of antigen

= Oakley and Fulthrope

= calther immunoelectrophoresis test

= Antibody is incorporated in a gel, above which a column of plain agar. The antigen is then layered on top of the agar medium.

If the antibody present reacts with the added antigen a precipitin band will form in the gel.

= Ouchterlony technique

= Holes are cut in the agar. One central hole will be made to be surrounded by other wells. Antibody is then added to the central well, antigens are added to the outer wells, the position of the bands formed between the antigen allows for comparison of the antigens to each other.

=  if the bands form an arc

 = Fusion of lines at their junction to form an arc(presence of common epitopes)

= if the bands fuse but there is a presence of spur.

=  Fusion of 2 lines partially (Precipitin lines do not form a complete cross)

= formation of pattern of lines which cross each other.

 = It demonstrate 2 separate reactions. (antigen shared no common epitopes)

= Laurell technique 

= One – dimensional electroimmunodiffusion, it is an adaptation of radial immunodiffusion (RID)

= A two – step double – diffusion technique which first involves the electrophoretic separation of proteins.

= Enhances the semiquantitation of antigens

= Double diffusion technique with the addition of electrophoresis to speed up the formation of a visible reaction

= Wells are made on each side of the gel and subjected to electrical field

= Similar to IEP except that after electrophoresis is performed the antiserum is applied directly to the surface of the gel 

= The best adaptation of this test is the Western Blot test - Current confirmatory method for HIV

- Agglutination of an antigen found naturally on a particle

- AKA Indirect Agglutination

- Uses carrier particles (latex, sheat RBC, charcoal) 

- Passive agglutination routinely used for detecting antibodies to viruses such as cytomegalovirus (CMV), rubella and varicella - zoster 

- Antibody is attached to carrier particle instead of the antigen

- Often use for detection of microbial antigens such as: Group A and B Streptococcus, Staphylococcus aureus, Neisseria Meningitidis, Haemophilus influenzae, Cryptococcus neoformans, Mycoplasma pneumoniae and Candida albicans

- Based on competition between particulate and soluble antigens for limited antibody combining sites.

- Reactive samples will not produce a visible result.

-  A type of agglutination wherein bacteria is used as a carrier.

- Used to identity Streptococci, Neisseria meningitidis, Neisseria gonorrhea and Haemophilus influenzae

- Staph auerus is comonly used carrier

Study of fluid components in the blood, especially antibodies

-Liquid portion of blood minus coagulation factors

- Most frequently encountered specimen in immunologic testing

- relationship between the two is expressed as ratio or fraction

- proportion of people who have a disease or condition and who have a positive test

- indicates how small an amount can be measured and still produce a positive test result

- proportion of people who do not have a disease or condition who have a negative test

- measures the substance that it is designed to measure, not interfering substances

- the probability that a person with a positive screening test actually has the disease

- the probability that a person with a negative screening test does not have the disease

- reactants are mixed together simultaneously

- the labeled antigen competes with unlabeled patient antigen for a limited number of antibody - biding sites

- should high affinity

- very specific for the antigen involve

- usually use monoclonal antibodies

- made up of known conc. of substance to be measured

- unlabeled analytes

- includes a solid-phase vehicle for separation

- specific binding takes place complexes are formed and remain attached to the solid phase

- Last step common to all immunoassays

- Limit random errors

scintillation counter

are membrane-based, single - use and disposable assays

- involved antigen or antibody coupled to the membrane

- use enzymes as labels, which react with suitable substrates to produce breakdown products may may be chromogenic, fluorogenic or luminescent

- used to determine the concentrations of therapeutic drugs and hormones

- employed to the follow antigen 0 antibody combination

- can be used for heterogenous and homogenous assays because labels can be attached to either antigen or antibody