Immunity Flashcards
Involves production of antibodies and generation of specialized lymphocytes against specific antigens
Immune response
Molecules from a pathogen or foreign organism that provokes a specific immune response molecular weight of >10,000
ANTIGEN
Small foreign molecule that is not antigenic
Must be coupled to a carrier molecule to be antigenic
Once antibodies are formed they will recognize hapten
HAPTEN
A critical aspect of an effective immune response is the ability to avoid unleashing its destructive mechanisms against the host’s own tissues
DISCRIMINATION OF “self vs nonself”
Avoidance of othe destruction of self-tissues
Failure of self-tolerance results in autoimmune diseases
Self-tolerance
The ability of the body to fight infection and/or foreign invades that tend to damage the tissues and organs by producing antibodies or killijg infected cell
IMMUNITY
Anaphylactic type
Type 1
Immediate hypersensitivity
Type 1
Reaction within minutes
May be systemic or localized
TYPE 1 (ANAPHYLACTIC TYPE; IMMEDIATE HYPERSENSITIVITY)
Ag binds to IgE on surface of sensitized mast cell and basophils
TYPE 1 (ANAPHYLACTIC TYPE; IMMEDIATE HYPERSENSITIVITY)
Present before birth
“Natural”
INNATE
Developed by exposure to pathogens or in a broader sense, antigens not recognized by the MHC
ADAPTIVE
A set of molecules displayed om cell surfaces that are responsible for lymphocyte recognition and “antigen presentation”
The MHC molecules control the immune response through recognition of “self” and “nonself” and severe as targets in transplantation rejection
MAJOR HISTOCOMPATIBILITY COMPLEX
Composed of two polypeptide chains
About 350 amino acids long
Glycosylated
Total molecular weight of about 45kDa
CLASS I MHC
Composed of two polypeptide chains
About 230 and 240 amino acids long
Glycosylated
Molecular weights of about 33 kDa and 28 kDa
CLASS II MHC
Anatomy of a lymph node
Naive lymphocytes circulate between blood and lymphoid tissues; antigen in tissue arrives at draining lymph node via lymph flow and being carried by dendritic cells
Proteins that recognize and bind to a particular antigen with very high SPECIFICITY
ANTIBODIES
One virus or microbe may have several antigenic determinant sites, to which different antibodies may bind
ANTIBODIES
Belong to a group of serum proteins called IMMUNOGLOBULINS (Igs)
ANTIBODIES
Primary immune response
IgG
Crosses the placenta
IgG
Most versatile immunoglobulin
IgG
Major Ig in serum 75%
IgG
Only class of Ig that crosses the placenta
IgG
Opsonizes bacteria for phagocytosis
IgG
FIXES COMPLEMENT enhancing bacterial killing, secondary responses
IgG
NEUTRALIZES bacteial toxins and viruses
IgG
Found on mucosal surfaces
Secretions (saliva, sweat, tears)
IgA