Immune system Flashcards
Antigens
Substances on the surface of agents that the body perceives as foreign
Pathogen
Dangerous foreign substances to the body
Allergies
Immuneoresponse to foreign agents that are not pathogens
Autoimmune disease
When the immune system mistakes part of the body as a pathogen
Innate immune system
The body’s first line of defense; a collection of nonspecific barriers- not defend against specific pathogens
Commensal microorginism
Normal bacterial flora
Name some antimicrobial substances in the body
Mucus, tears, saliva
What are some external (first line) aspects of the innate immune system?
Skin, hair, earwax, sweat, salt, enzymes, commensal microorganisms, mucus
What are some internal (second line) aspects of the innate immune system?
Inflammation, interferon, phagocytes, antimicrobials, NK lymphocytes
What is phagocytosis?
Ingestion of pathogens by WBC phagocytes
Macrophage
A phagocyte that uses digested antigens to alert T cells; also produces cytokines
Name 3 antigen presenting cells
Dendrite, B and macrophage
Cytokines
Molecules that signal the location of a pathogen to activate cytotoxic T cells (macrophage and helper T cells produce this)
Histamine
WBC that triggers capillary permeability and vasodilation so WB can leak to the infected tissues
Inflamation
Redness, swelling, heat, pain
Interferons
Proteins secreted by leukocytes that inhibit virus replication
Adaptive immune system
Specific responses to particular antigens
Lymphocytes
B calls and T cells
T-cells
Mature in the Thymus.
Helper T- interlukins- trigger action from other cells
Cytotoxic T- attack pathogens
Memory T- Respond quickly to re-exposed pathogen, preventing symptoms
Cell-mediated immunity
Adaptive immunity from T cells that attack parasites, cancer, transplanted tissues, etc.
B-cells
Mature in bone marrow and make antibodies in response to antigens; turn into plasma cells that release a shload of antibodies
Antibodies (immunoglobulins)
Blood proteins that fit specific antigens, marking them for destruction
Antibody-mediated immunity (humoral immunity)
Immunity by antibodies created by B-cells
Immunization
Active artificial immunity
Passive immunity
Temporary immunity gained from an outside source i.e. placenta or breast milk
Active immunity
Production of antibodies as a result in active antigens present in the body
