preview

Antibodies : Our Body 's Weaponry Essay

Better Essays

Antibodies: Our Body’s Weaponry
1: Introduction
Antibodies (Ab) or Immunoglobulins (Ig) are large diversities of ‘Y’ shaped glycoprotein molecules. The paratope which is at the tips of the ‘Y’ shaped molecule are extremely specific and exceptional to a particular epitope of an antigen (Ag) molecule. Upon binding to the antigen, antibodies can elicit an immune reaction in response to the antigen. Antibodies which are circulating in the lymph fluid or blood plasma are produced by B lymphocytes (Plasma B cells & Memory B cells). Hence, they play an important role in humoral immunity under Adaptive Immune System. There are five isotypes of antibodies namely IgA, IgD, IgE, IgG and IgM. In the following sections, the chemistry behind the structure and the physiology of antibody response will be discussed. In addition, applications of antibody molecules will be elaborated.
2: Structure of Antibody
Antibodies are made up of two identical heavy (H) chains and two identical light (L) chains as shown in Figure 1 below. Both the heavy and light chains consist of variable domains and constant domains. The variable domains (VH & VL shown in red in Figure 1) which are at the tip of ‘Y’ shaped molecules are responsible for the specificity as it is unique to a particular type of antigen. This is known as the antigen binding site (Fab). To ensure specificity, grooves present on top of Fab region must have a complementary shape with the epitope of the antigen. Constant region of the antibody

Get Access