Immune System: Human Health and Disease

A set of flashcards focusing on the nomenclature, mechanisms, and cell types involved in the human immune system, based on medical biology lecture notes.

Immunity

The overall ability of the host to fight the disease-causing organisms, conferred by the immune system, representing the resistance of the body against a pathogen or disease.

Antigen (Agglutinogen)

A substance which stimulates the production of antibodies.

Antibody (Agglutinin)

A complex glycoprotein secreted by B-lymphocytes in response to an antigen.

Agglutination

The term used to describe the antigen antibody reaction.

Serology

The study of antigen-antibody reaction.

Antiserum

Serum of any animal which contains the antibody for a specific antigen.

Venom (poison)

Toxic substances secreted by animals and some insects.

Toxoid

Inactivated toxins which are used as vaccines.

Innate Immunity

A non-specific type of defence that is present at the time of birth, accomplished by providing different types of barriers to the entry of foreign agents.

Str. corneum

The outermost dead layer of skin that prevents the growth or entry of micro-organisms into the body.

Skin pH

The acidic environment of the skin, typically recorded between $3$ and $5$, which destroys bacteria.

Mucosa

The mucus coating of epithelium lining the respiratory, gastrointestinal, and urogenital tracts that helps in trapping microbes.

Physiological Barriers

Body processes and environments such as acid in the stomach, saliva in the mouth, and tears from eyes that prevent microbial growth.

Lysozyme

An enzyme found in body secretions like tears and sebum that destroys microbes.

PMNL-neutrophils

Polymorpho-nuclear leukocytes (WBC) that can phagocytose and destroy microbes in the blood.

Macrophages

Large, irregular shaped cells in tissues that engulf microbes, virus, and cellular debris in response to an infection.

Natural Killer Cell

A large granular lymphocyte that kills virus infected cells and tumour cells by creating perforin lined pores in the plasma membrane of target cells.

Interferons

Anti-viral proteins made up to $270$ amino acids secreted by virus infected cells to protect non-infected cells from further viral infection.

T.I.P. (Translation Inhibiting Protein)

A protein produced by cells stimulated by interferons that limits the infection of a virus.

INFS-α

A substance that activates the immune system and destroys tumors, showing some success in causing regression of Kaposi sarcoma in AIDS patients.

Inflammation

A local response of living mammalian tissue to injury used to eliminate or limit the spread of infectious agents.

Rubor (Erythema)

Redness during inflammation caused by vasodilation.

Calor

Heat produced during inflammation because metabolic reactions proceed more rapidly.

Tumor (in Inflammation)

Swelling due to increased permeability of blood vessels.

Dolor

Pain resulting from injury to neurons and chemicals like prostaglandins released by damaged cells.

Acquired Immunity

Pathogen specific immunity characterized by memory of previous encounters.

Primary Response

A low intensity response produced by the immune system when it encounters a pathogen for the first time.

Secondary (Anamnestic) Response

A highly intensified and rapid immune response produced upon a subsequent encounter with a previously met pathogen.

B-lymphocytes

Special types of lymphocytes that produce an army of proteins called antibodies in response to pathogens.

T-lymphocytes

Specialized cells that do not secrete antibodies themselves but help B cells to produce them.

Active Immunity

A slow type of immunity where antibodies are produced in the host's body in response to antigens, such as during natural infection or vaccination.

Passive Immunity

Immunity provided when ready-made antibodies are directly given to protect the body against foreign agents, such as with antiserum or colostrum.

Colostrum

The yellowish fluid secreted by a mother during the initial days of lactation that has abundant antibodies (IgA) to protect the infant.