II. Mechanism

  1. Enzyme-linked antibodies, specific to a another Antibody or Antigen, are embedded in specific positions on a surface
    1. Surface is typically a labeled grid of wells
  2. Test solution containing a patient's serum or other body fluid is poured over the surface (immunosorbent substrate)
  3. The surface embedded antibodies on binding Antigens, activate enzymes resulting in a color change detected by machine
    1. Enzymes include horseradish peroxidase
    2. Degree of color change is proportional to the Antigen concentration in the test solution
    3. Machine detection is by spectrophotometry

III. Types

  1. Direct ELISA
    1. Standard ELISA method with single detection phase as described above
  2. Sandwich ELISA
    1. First ELISA phase binds non-specific Antigen (e.g. antibodies such as IgE)
    2. Second ELISA use the bound Antigen with additional markers to sub-classify the Antigen types
  3. Competitive ELISA
    1. ELISA method may use enzyme-linked Antigen instead of Antibody
    2. In first phase, a solution of Antibody binds to Antigen
    3. In next phase, another Antibody solution binds competitively to unbound or less specifically bound Antigen
  4. Reverse ELISA
    1. Antibodies and Antigens are incubated together
    2. Incubated fluid is moved to a scavenger container to remove unbound Antibody
    3. Remaining Antibody and Antigen complexes are measured via flow cytometry

IV. Labs: Examples

  1. HIV ELISA
  2. H. pylori ELISA
  3. Lyme ELISA
  4. RadioAllergoSorbent Test (RAST)
    1. Test for IgE Antibody related to Type 1 Hypersensitivity Reactions
    2. Performed as ELISA or with radiolabeled anti-IgE Antibody

V. Resources

VI. References

  1. Mahmoudi (2014) Immunology Made Ridiculously Simple, MedMaster, Miami, FL

Images: Related links to external sites (from Bing)

Related Studies

Ontology: Enzyme-Linked Immunosorbent Assay (C0014441)

Definition (CHV) a test called enzyme linked immunosorbent assay
Definition (HL7V3.0) <p>ELISA</p>
Definition (NCI_NCI-GLOSS) A laboratory technique that uses antibodies linked to enzymes to detect and measure the amount of a substance in a solution, such as serum. The test is done using a solid surface to which the antibodies and other molecules stick. In the final step, an enzyme reaction takes place that causes a color change that can be read using a special machine. There are many different ways that an ELISA can be done. ELISAs may be used to help diagnose certain diseases.
Definition (NCI) A highly sensitive technique for detecting and measuring antigens or antibodies in a solution; the solution is run over a surface to which immobilized antibodies specific to the substance have been attached, and if the substance is present, it will bind to the antibody layer, and its presence is verified and visualized with an application of antibodies that have been tagged in some way. (BioTech Life Science Dictionary)
Definition (NCI_CDISC) An immunoassay for detecting and measuring antigens or antibodies in a solution; the solution is run over a surface to which immobilized antibodies specific to the substance have been attached, and if the substance is present, it will bind to the antibody layer, and its presence is verified and visualized with an application of antibodies that have been tagged in some way.
Definition (MSH) An immunoassay utilizing an antibody labeled with an enzyme marker such as horseradish peroxidase. While either the enzyme or the antibody is bound to an immunosorbent substrate, they both retain their biologic activity; the change in enzyme activity as a result of the enzyme-antibody-antigen reaction is proportional to the concentration of the antigen and can be measured spectrophotometrically or with the naked eye. Many variations of the method have been developed.
Definition (CSP) immunoassay utilizing an antibody labeled with an enzyme marker such as horseradish peroxidase; while either the enzyme or the antibody is bound to an immunosorbent substrate, they both retain their biologic activity; the change in enzyme activity as a result of the enzyme-antibody-antigen reaction is proportional to the concentration of the antigen and can be measured spectrophotometrically or with the naked eye; many variations of the method have been developed.
Concepts Laboratory Procedure (T059)
MSH D004797
SnomedCT 76978006
HL7 0070
English Assay, Enzyme-Linked Immunosorbent, Assays, Enzyme-Linked Immunosorbent, ELISA, Enzyme Linked Immunosorbent Assay, Enzyme-Linked Immunosorbent Assay, Enzyme-Linked Immunosorbent Assays, Immunosorbent Assay, Enzyme-Linked, Immunosorbent Assays, Enzyme-Linked, enzyme linked immunosorbent assay, ELISA-Enz-link immunosor assay, Enzyme-linked immunosorb assay, Enzyme-linked immunosorbant assay, enzyme-linked immunosorbent assay, ELISA assay, ELISA - Enzyme-linked immunosorbent assay, Enzyme-linked Immunosorbent Assay, Enzyme-linked immunosorbent assay, Enzyme-linked immunosorbent assay (procedure), Enzyme-linked immunosorbant assay (procedure)
Dutch enzyme-linked immunosorbent assay, Assay, Enzyme-Linked Immunosorbent, ELISA, Enzyme-Linked Immunosorbent Assay
French Test ELISA (dosage immuno-enzymatique), Dosage immunoadsorbant lié aux enzymes, Test ELISA, ELISA (Enzyme-Linked ImmunoSorbent Assay), Dosage d'immunosorption liée à enzyme, Dosage ELISA, Dosage immunoenzymatique sur support solide
German Enzyme-linked immunosorbent assay, ELISA, Enzymimmuntest (ELISA)
Italian Test di immunoadsorbimento enzima-correlato, Test di immunoassorbimento enzimatico, ELISA
Portuguese Ensaio imunoabsorvente ligado às enzimas, Ensaio de Imunoadsorção Enzimática, ELISA, Ensaio Imunoadsorvente Ligado à Enzima, Ensaio de Imunoadsorção Ligado à Enzima, Ensaio Imunoadsorvente Enzima-Associado
Spanish Prueba de inmunoadsorción enzimática, ELISA, Ensayo de Inmunoadsorción Enzimática, Ensayo Inmunoadsorbente Enzima-Ligado, Test de ELISA, Ensayo Inmunoadsorbente Enzima-Enlazado, Ensayo de Inmunoadsorción Ligado a Enzimas, Prueba ELISA, ensayo de inmunoadsorción ligado a enzimas (procedimiento), ensayo de inmunoadsorción ligado a enzimas, prueba de ELISA
Japanese 酵素結合性免疫吸着検定法, ELISA, コウソケツゴウセイメンエキキュウチャクケンテイホウ, ELISA, 酵素結合免疫吸着剤検定, エライサ, エライザ, エリサ, サンドイッチ法, 固相酵素免疫測定法, 酵素結合免疫吸着剤検定法, 酵素結合抗体免疫アッセイ, 酵素結合抗体免疫吸着アッセイ
Swedish Enzymkopplad immunadsorberande analys
Czech ELISA, enzymoimunosorpční analýza, Enzymová imunoanalýza na pevné fázi
Finnish ELISA
Russian IMMUNOFERMENTNYI TVERDOFAZNYI ANALIZ, FERMENTY SVIAZANNYE, IMMUNOSORBENTNYI ANALIZ, ELISA, ИММУНОФЕРМЕНТНЫЙ ТВЕРДОФАЗНЫЙ АНАЛИЗ, ФЕРМЕНТЫ СВЯЗАННЫЕ, ИММУНОСОРБЕНТНЫЙ АНАЛИЗ
Croatian ELISA
Polish Metoda ELISA, ELISA
Hungarian Enzimmel jelzett ellenanyag vagy antigén kimutatás, ELISA
Norwegian Not Translated[Enzyme-Linked Immunosorbent Assay]