Hemagglutination

Hemagglutination

Hemagglutination (also haemagglutination) is a specific form of agglutination that involves red blood cells. It has two common uses in the laboratory: blood typing and the quantification of virus dilutions.

Blood Typing

Using antibodies that bind to the A or B blood group in a sample of blood, one can determine the blood type of the individual being tested.

For example, if antibodies that bound to the A blood group were added and agglutination occurred, it could be concluded that the blood was either type A or type AB.Then if antibodies that bound the B group were added and agglutination did not occur, it could be concluded that the blood was type A.

In blood grouping the patient's serum is tested against RBCs of known blood groups and also the patient's RBCs are tested against known serum types. In this way the patient's blood group is confirmed from both RBCs and serum. A direct Coombs test is also done on the patient's blood sample in case there are any confounding antibodies.

Viral Hemagglutination Assay

Many viruses attach to molecules present on the surface of red blood cells. A consequence of this is that - at certain concentrations - a viral suspension may bind together (agglutinate) the red blood cells thus preventing them from settling out of suspension. Usefully, agglutination is rarely linked to infectivity, attenuated viruses can therefore be used in assays.

By serially diluting a virus suspension into an assay tray (a series of wells of uniform volume) and adding a standard amount of blood cells an estimation of the number of virus particles can be made. While less accurate than a plaque assay, it is cheaper and quicker (taking just 30 minutes).

This assay may be modified to include the addition of an antiserum. By using a standard amount of virus, a standard amount of blood cells and serially diluting the antiserum, one can identify the minimum inhibitory concentration of the antiserum (the greatest dilution which inhibits hemagglutination).

External links

* [http://www.healthsystem.virginia.edu/internet/hematology/HessEDD/Redbloodcelldisorders/hemagglutination.cfm Hemagglutination] : Presented by the University of Virginia
*


Wikimedia Foundation. 2010.

Игры ⚽ Нужна курсовая?

Look at other dictionaries:

  • HÉMAGGLUTINATION — Agglutination des hématies aboutissant à la formation de petits amas visibles à l’œil nu, l’hémagglutination est une méthode très employée en immunologie pour détecter les anticorps et les antigènes. Il existe trois sortes de réactions… …   Encyclopédie Universelle

  • Hémagglutination — L’hémagglutination est une variante de la réaction d’agglutination. Elle est définie comme la fixation d’anticorps spécifiques sur des structures antigéniques présentes à la surface des globules rouges. Cette réaction aboutit à la formation d’un… …   Wikipédia en Français

  • Hemagglutination assay — The Hemagglutination Assay (HA) is a quantification of viruses by hemagglutination.Some viral families have surface or envelope proteins, that are able to agglutinate (stick to) human or animal Red blood cells (RBC) and bind to its N… …   Wikipedia

  • hemagglutination inhibition test — 1. a highly sensitive procedure for the measurement of soluble antigens in biologic specimens; the specimen is first incubated with homologous antibody and then incubated with antigen coated red blood cells; the amount of hemagglutination… …   Medical dictionary

  • hemagglutination — noun Date: 1907 agglutination of red blood cells • hemagglutinate transitive verb …   New Collegiate Dictionary

  • hemagglutination — (hem ah gloo tī na shun) The agglutination of red blood cells by antibodies …   Dictionary of microbiology

  • hemagglutination — /hee meuh glooht n ay sheuhn, hem euh /, n. the clumping of red blood cells. [1905 10; HEM + AGGLUTINATION] * * * …   Universalium

  • hemagglutination — noun The agglutination of red blood cells …   Wiktionary

  • hemagglutination — The agglutination of red blood cells; may be immune as a result of specific antibody either for red blood cell antigens per se or other antigens which coat the red blood cells, or may be nonimmune as in h. caused by viruses or other microbes. SYN …   Medical dictionary

  • hemagglutination — n. clumping together of red blood cells …   English contemporary dictionary

Share the article and excerpts

Direct link
… Do a right-click on the link above
and select “Copy Link”