The very basic structure of an immunoglobulin (antibody) molecule can be demonstrated under following points: Polypeptide chains: Antibody molecules have a common structure of four polypeptide chains, having two different sizes. These are a pair of identical high molecular weight chains called Heavy chains (H-chains) and a pair of identical low molecular weight chains called Light chains (L-chains). Each light [...]
In this article we will discuss about the characteristics of epitopes. 1. An antibody that is specific for an antigen binds non-covalently to a region of the molecule surface known as epitope. 2. Naturally occurring epitopes are relatively small (either amino-acids or sugar residues). 3. Specific epitope should fit with the specific site present on antibody (antibody-binding site). 4. The [...]
The following points highlight the two main types of organs present in immune system of humans. The types are: 1. Primary Lymphoid Organs 2. Secondary Lymphoid Organs. Type # 1. Primary Lymphoid Organs: Primary lymphoid organs (PLO) are the major sites of lymphocyte development i.e. lymphopoiesis. Lymphocytes differentiate from lymphoid stem cells, proliferate and mature into functional cells called immuno-competent [...]