UNIT 2.3 Double-Immunodiffusion Assay for Detecting Specific Antibodies

  1. Peter Hornbeck

Published Online: 1 MAY 2001

DOI: 10.1002/0471142735.im0203s00

Current Protocols in Immunology

Current Protocols in Immunology

How to Cite

Hornbeck, P. 2001. Double-Immunodiffusion Assay for Detecting Specific Antibodies. Current Protocols in Immunology. 00:I:2.3:2.3.1–2.3.4.

Author Information

  1. University of Maryland, Baltimore, Maryland

Publication History

  1. Published Online: 1 MAY 2001
  2. Published Print: DEC 1991

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Double immunodiffusion owes its success to the unique nature of antibody-antigen interactions. When polyvalent antibodies with moderate-to-high intrinsic affinities are mixed with antigen at the right ratio (called the zone of equivalence) lattices of antibody-antigen complexes form and precipitate out of solution. When, as described in this unit, gradients of antigen and antibody are established by diffusion from adjacent wells in a bed of agar, a line of practically insoluble precipitation forms at the equivalence zone (precipitin lines).