This may or may not be what you had in mind, but the first line of defense is the skin, which keeps out pathogenic organisms. Then there is the immune system.
White blood cells
how do vaccines help the bodys natural defences against viruses ??
actually the body does nothing to diseases. BUT. its what diseases do to tha body. thus, the body contracts all sorts of disease and viruses. when these foreign bodies (disease and virus ) enters the body, it is destroyed by white-blood cells which is the human bodys' main defence against viruses and diseases that wants to enter the body to make u i'll.
immune system
its killer T cells
Our bodies have many natural defences. Our main internal defence would be our immune system which helps combat bacterial and viral diseases. Our main external defence would be our skin which protects our body and prevents pathogens and microbes from entering our bodies. Hope This Helps :D
yes because some of them tests your bodys defence levels
Autoimmunity
What they do is build your bodys self defence cells up so you dont catch dieseases as easily.
Neutrophils
There are perhaps hundreds of diseases that attack joints. The effect on the joints is called Arthritis.
Barriers, The Inflammation Process, and Antibodies.