Online microbiology and biology related notes by SAGAR ARYAL
Complement Components Complement refers to a set of serum proteins that cooperates with both the innate and the adaptive immune systems to eliminate blood and tissue pathogens. Complement components can be classified into seven functional categories: Initiator complement components: These proteins initiate their respective complement cascades by binding to particular soluble or membrane-bound molecules. Once … Read moreComplement Components
Complement- Properties and Nomenclature Complement refers to a set of serum proteins that cooperates with both the innate and the adaptive immune systems to eliminate blood and tissue pathogens. Various complement components bind and opsonize bacteria, rendering them susceptible to receptor-mediated phagocytosis by macrophages, which express membrane receptors for complement proteins. Other complement proteins elicit … Read moreComplement- Properties and Nomenclature
Latex Agglutination Test When a particulate or insoluble antigen is mixed with its antibody in the presence of electrolytes at a suitable temperature and pH, the particles are clumped or agglutinated. Agglutination reactions are classified as direct, indirect (passive) and reverse passive agglutination reactions. Direct Agglutination Test refers to the assays in which the antigen directly … Read moreLatex Agglutination Test
Rapid Plasma Reagin (RPR) like the Venereal Disease Research Laboratory (VDRL) test is a screening test for syphilis which is a sexually transmitted infection caused by the spirochete bacterium Treponema pallidum. It is a rapid non-treponemal test that looks for non-specific antibodies in the blood of the patient that may indicate a syphilis infection. The test does not look for antibodies against … Read moreRapid Plasma Reagin (RPR) Test
Coomb’s test is a direct agglutination reaction, more commonly known as antiglobulin test. It was discovered by Coombs, Mourant and Race in 1945 originally for the detection of incomplete anti-Rh antibodies. In the test, incomplete antibodies do not agglutinate erythrocytes. Incomplete antibody antiglobulin coats the surface of erythrocytes but does not cause any agglutination. When … Read moreCoomb’s Test- Direct and Indirect Coomb’s Test
The Venereal Disease Research Laboratory test (VDRL) is a screening test for sexually transmitted infection – syphilis caused by the spirochete bacterium Treponema pallidum. It is a non-treponemal test, which detects antibodies IgM and IgG antibodies to lipoidal material released from damaged host cells as well as to lipoprotein-like material, and possibly cardiolipin released from the treponemes. These antibodies are … Read moreVenereal Disease Research Laboratory (VDRL) Test
Rocket Immunoelectrophoresis is an adaptation of radial immunodiffusion developed by Laurell. It is also known as electroimmunoassay or electroimmunodiffusion. It is called as “rocket electrophoresis” due to the appearance of the precipitin bands in the shape of cone-like structures (rocket appearance) at the end of the reaction. In rocket immunoelectrophoresis, antigen migrates in an electric field … Read moreRocket Immunoelectrophoresis- Objectives, Principle, Procedure, Results, Applications, Advantages and Limitations
Immunoelectrophoresis refers to precipitation in agar under an electric field. It is a process of combination of immuno-diffusion and electrophoresis. An antigen mixture is first separated into its component parts by electrophoresis and then tested by double immuno-diffusion. Antigens are placed into wells cut in a gel (without antibody) and electrophoresed. A trough is then … Read moreImmunoelectrophoresis- Principle, Procedure, Results and Applications, Advantages and Limitations
Immuno-diffusion is a technique for the detection or measurement of antibodies and antigens by their precipitation which involves diffusion through a substance such as agar or gel agarose. Simply, it denotes precipitation in gel. It refers to any of the several techniques for obtaining a precipitate between an antibody and its specific antigen. This can … Read moreRadial Immunodiffusion- Objectives, Principle, Procedure, Results, Applications, Advantages and Limitations
Interactions of antibodies and antigens, in the form of various tests, have been developed to determine the presence or absence of antibodies or antigens in a sample. A type of interaction between soluble antigens with its specific antibody in a suitable medium that results into the formation of an insoluble complex that precipitates is termed … Read moreRing Precipitation Test- Objectives, Principle, Procedure, Results and Examples