What is the Difference Between Exogenous and Endogenous Antigens

Endogenous antigens are antigens found within the cytosol of human cells such as viral proteins, proteins from intracellular bacteria, and tumor antigens. Exogenous antigens are antigens that enter from outside the body, such as bacteria, fungi, protozoa, and free viruses.

1. What are endogenous antigens?
2. What is the difference between processing of endogenous antigens and processing exogenous antigens?
3. What are 3 types of antigens?
4. How are exogenous antigens processed and presented?
5. Which is an example of endogenous antigen?
6. Are antigens good or bad?
7. What is the purpose of antigen processing?
8. What is an exogenous antigen?
9. What is MHC I and MHC II?
10. What is a good antigen?
11. Is a virus an antigen?
12. What is the largest type of antigen?

What are endogenous antigens?

Endogenous antigens are that have been generated within previously-normal cells as a result of normal cell metabolism or because of viral or intracellular bacterial infection (which both change cells from the inside in order to reproduce).

What is the difference between processing of endogenous antigens and processing exogenous antigens?

The main difference between exogenous and endogenous antigens is that the exogenous antigens enter the body from the outside whereas the endogenous antigens are generated inside the body. Exogenous and endogenous antigens are the two main types of antigens in the body. They are classified based on the origin.

What are 3 types of antigens?

The three broad ways to define antigen include exogenous (foreign to the host immune system), endogenous (produced by intracellular bacteria and virus replicating inside a host cell), and autoantigens (produced by the host).

How are exogenous antigens processed and presented?

Exogenous proteins, however, are primarily presented by MHC-II molecules. Antigens are internalized by several pathways, including phagocytosis, macropinocytosis, and endocytosis, and eventually traffic to a mature or late endosomal compartment where they are processed and loaded onto MHC-II molecules.

Which is an example of endogenous antigen?

Endogenous antigens are proteins found within the cytosol of human cells. Examples of endogenous antigens include: ... proteins that have escaped into the cytosol from the phagosome of phagocytes such as antigen-presenting cells; tumor antigens produced by cancer cells; and.

Are antigens good or bad?

Antigens are any substances that the immune system can recognize and that can thus stimulate an immune response. If antigens are perceived as dangerous (for example, if they can cause disease), they can stimulate an immune response in the body.

What is the purpose of antigen processing?

Antigen processing, or the cytosolic pathway, is an immunological process that prepares antigens for presentation to special cells of the immune system called T lymphocytes. It is considered to be a stage of antigen presentation pathways.

What is an exogenous antigen?

Exogenous antigens are antigens that have entered the body from the outside, for example, by inhalation, ingestion or injection. ... By endocytosis or phagocytosis, exogenous antigens are taken into the antigen-presenting cells (APCs) and processed into fragments.

What is MHC I and MHC II?

MHC I molecules are expressed on all nucleated cells and are essential for presentation of normal “self” antigens. ... MHC II molecules are expressed only on the surface of antigen-presenting cells (macrophages, dendritic cells, and B cells). Antigen presentation with MHC II is essential for the activation of T cells.

What is a good antigen?

Characteristics of a good antigen include:

A minimal molecular weight of 8,000–10,000 Da, although haptens with molecular weights as low as 200 Da have been used in the presence of a carrier protein. The ability to be processed by the immune system.

Is a virus an antigen?

“Antigens” are molecular structures on the surface of viruses that are recognized by the immune system and are capable of triggering an immune response (antibody production). On influenza viruses, the major antigens are found on the virus' surface proteins (see Figure 1).

What is the largest type of antigen?

The largest type of antigen is called a hapten.