Antibodies are included in second line of defense or in third line of defense(the complement proteins are antibodies) or not?

1 Answer
Jan 1, 2018

Antibodies are part of the third line of defense in the immune system.


The body's immune system has three lines of defense:

  1. Physical/Chemical. This is innate and non-specific and includes the skin, mucus, cilia, hair, gastric acid, urine, tears, saliva, etc.

  2. Nonspecific Resistance. This is also innate and comprises phagocytes which ingest foreign particles, inflammation and fever.

  3. Specific Resistance. This is acquired in response to antigens (reactive proteins) on the foreign particles which stimulate an antibody response through the involvement of T-cells and B-cells.