# data[].attributes.body
Antigen is defined as a foreign substance, microbes, or component of cell that stimulates immune response. Antigens are on individuals cells to help identify as "self" cells verses foreign cells. Antigens that are not "self" cells will trigger the immune response.

# data[].attributes.body
The Complement system is defined as a group of inactive proteins in the circulation that, when activated, stimulate the release of other chemical mediators, promoting inflammation, chemotaxis, and phagocytosis. It's a type of chemical mediator which is defined as an endogenous chemical agent which takes an active part in the development of the inflammatory response.

The complement system is frequently activated during an immune reaction with IgG- or IgM-class immunoglobulins. Complement involves a group of inactive proteins, numbered C1 to C9, that circulate in the blood. When an antigen-antibody complex binds to the first complement component, C1, a sequence of activating steps occurs (similar to a blood clotting cascade). Eventually this activation of the complement system results in the destruction of the antigen by lysis when the cell membrane is damaged, or some complement fragment may attach to a microorganism, marking it for phagocytosis. Complement activation also initiates an inflammatory response.

# data[].attributes.attachment_caption
T cells come from the Thymus, B Cells come from Bone Marrow. 

# data[].attributes.body
A Macrophage engulfs a pathogen and presents on the outside a foreign antigen initiating the immune system to activate. A T helper cell attaches to the Macrophage and determines to activate B or T lymphocytes. B lymphocytes mediate Humoral Immunity. So, if B cells are activated it in turns activates Humoral Immunity. After a B cell is exposed to antigens, and with the assistance of T lymphocytes, they become antibody-producing plasma cells. Depending on the type of antigen will determine which antibody the B cell will need to produce to fight the antigen. The B cell will release the antibody, and from there the antibody will attach to the antigen. Once the antibody has attached to the antigen it will make the cell unable to reproduce/cease to function. From there Complement system will activate to destroy the antigen causing phagocytosis.

B lymphocytes act primarily against bacteria and viruses that are outside body cells. B-memory cells that provide for repeated production of antibodies also form a part of the humoral immune response.

Antibodies are a specific class of proteins termed immunoglobulins and are present in different body fluids. Each has a unique sequence of amino acids (variable portion, which binds to antigen) attached to a common base (constant region, which attaches to macrophages).

# data[].attributes.body
Macrophage engulfs a pathogen and presents on the outside a foreign antigen initiating the immune system to activate. A T Helper cell attaches to the Macrophage and determines whether to activate B or T lymphocytes. T Lymphocytes mediate Cell Mediated Immunity. So, when T Helper cells activate T cells it activating Cell Mediated Immunity. T cells will directly destroy invading antigens. T cells will also reproduce an "Army" to fight the pathogens. T cells are primarily effective against virus-infected cells, fungal and protozoal infections, cancer cells, and foreign cells such as transplants.

There specific duties assigned to various T cells based on receptor molecule;  CD8-positive T-killer cells destroy the target cell by binding to the antigen and releasing damaging enzymes or chemicals, such as monokines and lymphokines, which may destroy foreign cell membranes or cause an inflammatory response, attract macrophages to the site, stimulate the proliferation of more lymphocytes, and stimulate hematopoiesis. Phagocytic cells then clean up the debris. The helper CD4-positive T cell facilitates the immune response.

# data[].attributes.body
Short video explaining the big differences between the 2 immunities.

# data[].attributes.body
Adaptive Immunity is the big umbrella Cell mediated immunity and Humoral Immunity fall under which is a specific response. The first and second defense systems are non-specific responses.

# data[].attributes.body
On the left is cellular immunity, the right is humoral Immunity.

# data[].attributes.body
Cell Mediated Immunity (CMI) or cellular immunity is an immune response that does not involve antibodies

Humoral Immunity (HI) response is mediated by antibody molecules that are secreted by plasma cells