Precipitation & Electrophoresis

involves combining soluble antigen with soluble antibody to produce insoluble complexes that are visible

Precipitation

Simplest method for detection of antigen-antibody reactions

Precipitation

Either antigen or antibody remains fixed, and the other reactant moves and complexes with it

One dimensional Diffusion

Simple and specific method for identification and quantitation of a number of proteins found in human serum and other body fluids

Single radial diffusion

The area of precipitation ring is proportional to antigen concentration

Mancini/Endpoint RID

The diameter of precipitation ring is proportional to log of antigen concentration

Fahey-Mckelvey/Kinetic RID

Double immunodiffusion is also known as ____

Ouchterlony method

Antigen and antibody are allowed to diffuse in a semisolid medium such as agar. When antigen and antibody meets, a precipitate forms

Double immunodiffusion

A single smooth arc of precipitation forms between the antigen and antibodies, indicating that the antibodies are precipitating IDENTICAL antigen specificities

Identity

Two separate lines of precipitation cross each other, indicating that the antigens and antibodies are unrelated and do now precipitate together

Nonidentity

Two precipitating lines meet, forming SPUR. This indicates that the antigens share some common epitopes, but that one of the antigens has a unique epitope

Partial identity

Essentially double diffusion technique in which voltage is applied to move the antigens and antibodies together

Countercurrent immunoelectrophoresis

QUANtitative test (more for antigen). Applies an electrical charge to a RID assay, resulting in a rocket shaped line of precipitation

Rocket electrophoresis

The height of the rocket is directly proportional to the antigen concentration

True

Specimen of choice in immunoelectrophoresis

Both

Stain for IEP

Coomasie brilliant blue

Albumin marker of EIP

Bromphenol blue

Preservative of IEP

Sodium azide

Determine qualitatively the increase or decrease of specific classes of immunoglobulins.

Detect structure and concentration changes in proteins

Immunoelectrophoresis

Identifies exact type of immunoglobulins present. Two stage procedure using agarose gel protein

Immunofixation electrophoresis

Stain of IFE

Amido Black

Diagnosis of monoclonal gammopathies, MM, Bence jones

IFE