Antibodies, also called immunoglobulins, are important proteins made by special cells known as B cells. They help our body fight off germs and other harmful invaders. Here’s a simple breakdown of how they work:

1. Basic Structure:

   • Antibodies are shaped like a Y. They have four chains: two heavy chains and two light chains.
   • The ends of the Y (called the variable region) grab onto specific invaders, which we call antigens. The base of the Y (called the constant region) helps determine what type of antibody it is and how it works in the immune system.

2. Classes of Immunoglobulins:

   • There are five main types of antibodies:
     • IgG (makes up 70-75% of antibodies in your blood)
     • IgA (15-20%)
     • IgM (5-10%)
     • IgD (less than 1%)
     • IgE (less than 1%)
   • IgG is the most common and helps protect us the most against germs.

3. Functions:

   • Neutralization: Antibodies can stop toxins and germs by sticking to them.
   • Opsonization: Antibodies make it easier for immune cells to recognize and eat pathogens by covering them.
   • Complement Activation: Antibodies can start a process that leads to breaking down the germs.

In summary, antibodies are essential for spotting and attacking bad invaders. They play a big role in our immune system. This is especially important when it comes to vaccines, which work by making our body produce antibodies. So, when we get vaccinated, our body learns to fight off specific germs more effectively!