Immunology Flashcards
Innate Immunity
Built in; pre-exposure not required; nonspecific; Sets off the inflammatory response; immediate
Adaptive immunity
Exposure to antigen required; specific; slower
IgM
First antibody produced against new antigen
Agglutinates (precipitates) antigen
Can activate complement
IgG
Most abundant
Only one to cross placenta
Attaches to inflammatory cells via Fcportion (found on macrophages, neutrophils, lymphocytes, and eosinophils)
Can serve as opsonin
IgA
Present in blood and mucosal secretions
Helps protect against mucosal invasion
IgE
Does not circulate in blood
Found primary in tissue bound to mast cells
Releases histamine
IgD
Function not well understood
Found on surface membranes of B lymphocytes (may work in hormonal function)
Contrast innate immunity
Quick, non-specific, “built in”
Adaptive immunity
Slower, specific, in response to an antigen
Role of Human Leukocyte Antigens
Identify self
T cells
Origin: bone marrow, programming (recognition of self vs nonself): Thymus
CD4
Helper cells that aid B cells
CD8
Suppress Bcells and CD4 T cells or kill foreign or infected cells
B-cells
Origin and programming in bone marrow
plasma Cells
Antibody (Ab or immunoglobulin) factories
Memory B-cells
Remember previous exposure to antigen, promoting quicker antibody production
NK cells
Origin: bone marrow; innately attack and kill cancer, foreign, and infected cells
Contrast cellular immunity
Ag -> activated T cells
Humoral immunity
Ag -> activated B cells -> plasma cells -> Ab
Describe structure of antibodies
Heavy chains (2) + light chains (2)
Fc (Constant region -> Ab subclass)
Fab (variable region -> specificity)
IgM
Earliest made
IgG
Made after IgM; longer lasting; crosses placenta
IgA
In mucosal secretions
IgE
On mast cells (-> histamine release seen with allergies)
