Elisa introduction.ppt : C & BE : NCP

Slide 1:

CONTENTS Antigens. Antibodies Immunoassay Different Types Of Immunoassay Different Immunological Tests Introduction To Elisa INTRODUCTION TO ELISA

ANTIGEN:

ANTIGEN It is an organic compound a protein, polysaccharide (OR) glycolipid. When entered into the body it induced immune responses by production of antibodies The antibodies so produced neutralizes (OR) destroy the antigen By measuring the concentration of specific antibodies present in the individual (OR) the population it is possible to determine the level of susceptibility and resistance to the infection.

ANTIBODIES:

ANTIBODIES It is a complex globular protein produced by B-Lymphocytes in response to antigen. Every antibody is made up of heavy chain and light chain molecules HEAVY CHAIN: 450 aminoacids LIGHT CHAIN: 215 aminoacids

Slide 4:

Depending on aminoacids sequence present on heavy chain of aminoacids the antibodies are classified into Ig A(ALPHA) Ig D(DELTA) Ig E(EPISILON) Ig G(GAMMA) Ig M ( µ) Humans can produce many specific antibodies . This may be active process by healthy host in response to exposure to foreign antigen (OR) antigens transmitted by placenta (OR) maternal milk from mother to offspring (OR) artificially induced by immunization with live attenuated organisms.

HOW ANTIBODIES ARE PRODUCED?:

HOW ANTIBODIES ARE PRODUCED?

IMMUNOASSAY:

IMMUNOASSAY Immunoassay are biochemical tests used to detect (OR) quantify specific antibodies and antigens as in the analyte (blood, urine, bodyfluids). Immunoassay has been developed for number of antibodies for identification and detection of antigen and their products. Immunoassay measures the formation of antigen-antibody complex and detect them. The detection can be done by measuring turbidity, light scattering, radioactive labeling, (OR) chemiluminescent molecule.

DIFFERENT TYPES OF IMMUNOSSAY:

DIFFERENT TYPES OF IMMUNOSSAY Radio Immunoassay. Fluorescent Immunoassay. Chemiluminescent Immunoassay. Enzyme Immunoassay.

IMMUNOLOGICAL TESTS :

IMMUNOLOGICAL TESTS Agglutination tests : In this reaction between antibody and antigen occurs. Fluorescent antibody test : In this the reaction between a labelled antigen and a particular antibody occurs and can be visualised using U.V spectroscopy. ELISA : In this the reaction between enzyme labelled antibody and antigens occurs.

ENZYME LINKED IMMUNOSORBENT ASSAY(ELISA):

ENZYME LINKED IMMUNOSORBENT ASSAY(ELISA) In 1971 Peter Perlmann & Eva Engvall at Stockholm university in Sweden & Anton Schuurs, Bauke Van Weemen in Netherlands independently published papers about method to perform ELISA. Before elisa the only method to perform immunoassay is radioimmunoassay. Today fully automated instrument in medical laboratories around the world use immunoassay principle with an enzyme as reported label.

APPLICATIONS:

APPLICATIONS ELISA in diagnosis of AIDS. Screening donated blood. Measuring hormone level. Used in toxicology. Used in food industry. Identification and detection of selected proteins. Elisa test can also be used to determine the affinity of antibodies to antigens. Used to determine antibody level in faecal content