Antibodies vs Immunoglobulins
(Why are Antibodies called as Immunoglobulins?)
All Antibodies are Immunoglobulins but all Immunoglobulins are NOT Antibodies.
Antibodies are the antigen binding proteins found on the B-cell membrane and secreted by the plasma cells of the immune system. Antibodies are commonly called as ‘IMMUNOGLOBULINS’. In the present post we will see, what is the exact difference between an Immunoglobulin and an Antibody, and also why antibodies are called immunoglobulins?
What are Antibodies?
Ø Antibodies are globular proteins (globulins) present in the serum and tissue fluids.
Ø They form one of the major components of the blood plasma proteins.
Ø In the blood, three types of globulin proteins are present and they are named as alpha (α), beta (β) and gamma (γ) globulins.
Ø All antibodies are gamma (γ) globulins.
Ø Antibodies confer protection against microbial pathogens and, they act as the first line defense against infections.
Ø Antibodies are highly specific and they specifically bind to foreign particles called antigens.
Ø The antibodies can protect us from the invading microbes in four different ways:
1. They can prevent the attachment of microbes to the mucosal surface of the host.
2. They reduce the virulence of the pathogen by neutralizing the toxins and viruses.
3. They facilitate phagocytosis by opsonization of microbes.
4. They can activate the complement system.