Question

Define Antigen and Antibody. Name any two diagnostic kits based upon them.

Answer 1

Antigen :

Antigens are foreign substances that have the ability to elicit an immune response in the body. Examples include dust, pollen grains, pathogenic bacteria etc.

Antibody Antibodies are immunoglobulins synthesized by the immune system against the antigen.

Principle behind antigen - antibody interaction :

Antibodies possess sites for binding with antigens. These interactions result in the visible clumping of antigen - antibody complexes called agglutination. This can be detected.

Diagnostic kits based on antigen - antibody reaction :

Two diagnostic kits based on antigen-antibody interactions are as follows:

1. ELISA kit - It is used for the detection of HIV/AIDS infection. This kit detects the antibodies produced in the host organism against Human Immunodeficiency Virus.

2. Pregnancy test kit -It detects the presence of human chorionic gonadotropin (HCG) hormone in the urine of a pregnant female.