If you're not familiar with the basics of how the immune system works to be able to attack pathogens that could result in diseases within the body, then how is it possible for you to understand how the scientists exploit this system to use in the body's favor when it can't deal with undetectable pathogen, this is why we'll begin with how the immune system works and understand the basics.

Mainly the body's natural immune system is like a network of cells where their main function is the body's defense from antigens, antigens are antibody generators, that is because they're mainly foreign to the body, and through these antibodies the immune system could attach to them and allow the immune system to attack, examples of these antigens include:bacteria,viruses, fungi &allergens.

The natural immune response of the body goes about producing these antibodies to attack specific antigens that are foreign , while in the case of the autoimmune diseases , like arthritis or lupus , they occur due to the over activity of the immune responses towards the proteins within the body .

Mainly an antigen whenever it's introduced to the body through inhalation or ingestion or even direct skin contact or through the mucous membranes of the body lead to the production of antibodies or an immune response , and these antibodies are mainly the way the immune response goes about marking the perpetrator to be able to attack him at once and end the threat , an example of this treatment that is synthetic is monoclonal antibodies that are designed to act in the same way these natural antibodies work .

Now that we know that basics,let's take a look at the different types of immune cells and how they play a role in the body's immune response.

B Lymphocytes (B cells) they're responsible for allowing the antibodies to find the antigens and bind to them, they're located in the bone marrow and other parts of the lymphatic system.

T Lymphocytes (T cells) they have many uses including heling B cells produce antibodies to battle invading microbes.

Natural Killer Cells (NK cells) naturally attack cancer cells directly without having to recognize an antigen.

Phagocytes which are responsible for swallowing up and digesting microscopic bodies like bacteria or cells that are dying, examples of these cells include dendritic cells or macrophages.

And this includes our quick look at how the immune system works to help us understand how immunotherapy works.