"An antigen (Ag) is a molecule, moiety, foreign particulate matter, or an allergen, such as pollen, that can bind to a specific antibody or T-cell receptor."
Antigens are substances that trigger an immune response by the production of antibodies.
Immunology: The study of the immune system, including how it protects against foreign invaders such as antigens.
Antigen: A substance that triggers an immune response, often a protein or carbohydrate on the surface of a pathogen or abnormal cell.
Antibody: A protein produced by the immune system that can recognize and bind to a specific antigen, leading to its destruction.
Epitope: The specific region of an antigen that is recognized by an antibody.
Major histocompatibility complex (MHC): A set of genes that encode for proteins on the surface of cells that help the immune system recognize and respond to antigens.
T cells: A type of white blood cell that can recognize and respond to specific antigens, either by directly attacking cells presenting the antigen or by sending signals to other cells in the immune system.
B cells: A type of white blood cell that can produce antibodies against specific antigens.
Immune response: The cascade of events that occurs when the immune system detects an antigen, leading to the activation of immune cells and the production of antibodies.
Immunoglobulin: A type of protein that includes antibodies and serves various roles in the immune system, such as recognizing and neutralizing antigens.
Immunosuppression: The deliberate or unintentional suppression of the immune system, which can increase the risk of infections or allow cancer cells to grow unchecked.
Microbial antigens: Antigens derived from microorganisms such as bacteria, fungi, viruses, and parasites.
Self-antigens: Antigens derived from a person's own cells and tissues.
Environmental antigens: Antigens derived from environmental sources such as pollen, dust, and chemicals.
Food antigens: Antigens found in various types of food.
Tumor antigens: Antigens expressed by cancer cells.
Blood group antigens: Antigens found on the surface of red blood cells that determine blood type.
Hapten antigens: Small molecules that can stimulate an immune response only when they are bound to a larger carrier molecule.
Allergens: Antigens that cause allergic reactions.
Superantigens: Antigens that activate a large number of T cells and can cause a severe immune response.
Autoantigens: Antigens that are recognized by the immune system as foreign, even though they are derived from the body's own cells and tissues, and can cause autoimmune diseases.
"Antigens can be proteins, peptides (amino acid chains), polysaccharides (chains of simple sugars), lipids, or nucleic acids."
"Antigens exist on normal cells, cancer cells, parasites, viruses, fungi, and bacteria."
"Antigens are recognized by antigen receptors, including antibodies and T-cell receptors."
"Upon exposure to an antigen, only the lymphocytes that recognize that antigen are activated and expanded, a process known as clonal selection."
"In most cases, antibodies are antigen-specific, meaning that an antibody can only react to and bind one specific antigen."
"The reaction between an antigen and an antibody is called the antigen-antibody reaction."
"Antigen can originate either from within the body ('self-protein' or 'self antigens') or from the external environment ('non-self')."
"The immune system identifies and attacks 'non-self' external antigens."
"Antibodies usually do not react with self-antigens due to negative selection of T cells in the thymus and B cells in the bone marrow."
"The diseases in which antibodies react with self antigens and damage the body's own cells are called autoimmune diseases."
"Vaccines are examples of antigens in an immunogenic form, which are intentionally administered to a recipient to induce the memory function of the adaptive immune system towards antigens of the pathogen invading that recipient."
"The vaccine for seasonal influenza is a common example." Note: To complete the list of twenty study questions, you may need to develop additional questions based on the provided paragraph.