Week 1- Lec 1- Immunity Flashcards
What is the haptene-carrier adduct?
-immune response to smaller molecules
Haptene: small molecule that is somewhat antigenic but alone cannot elicit an immune response
Carrier: large immunogenic molecule that when coupled with haptene will elicit an immune response
What is phagocytosis?
engulf and digestion of AG; neutralize
Antigen Presenting Cells(APC)- What is it?
macrophage, dendritic cell or B lymphocytes recognize AG & present to effector cells
Antigen recognition is done by what component of the immune system?
lymphocytes which include B or T cells
What is the process of antigen processing?
AG links to appropriate Major Histocompatibility Complex(MHC) and lymphocyte receptor
Classification of antigens:
Source? Type? Example? Significance?
Exogenous - Several -Microorganisms , drug, pollen- susceptibility to infection; asthma
Endogenous- Xenoantigen -Tissue AG cross- react w/ exogen. AG - Post-strep glomerulonephritis; rhematic fever; pathogenesis of immune disease
Autologous- autoantigen- organ specific AG-autoimmune disease (SLE, RA, Diabetes)
Allogenic- Alloantigen- Blood group; HLA- transfusion reactions; transplant rejection
What are epitopes?
Antigen determinants on antigen
Innate immunity vs adaptive immunity
Innate Immunity-
-Present at birth
uses pre-existing cells, mediators and/or receptors to identify and eliminate pathogens from host.
Acquired or Adaptive Immunity
- the Host’s immune ability to develop a specific immune protection against foreign invading substance or antigen (AG).
- Cell mediated Immune response
- Humoral Immune Response
Innate leukocytes consist of?
Neutrophils, eosinophils, monocytes & dendritic cells
What are toll-like receptors?
family of pattern recognition receptors(PRR) on surface of innate Antigen-Presenting cells (APC) (neutrophils ;dendritic cell, macrophage)
Binding of AG ligand to TLR enables phagocytes to recognize & engulf pathogen.
What are pathogen associated molecular patterns?
Pattern recognition receptos recognize antigens through PAMPS
Which cell does all immune cells arise from
hematopoietic stem cell
B lymphocyes function
recognize soluble or cell surface AG and differentiate into antibody(AB) forming Plasma Cells.
T Helper Lymphocytes(CD4+ cells) function:
recognize AG on surface of Antigen Presenting Cells(APC) and secrete specific cytokines that stimulate other immune cell responses and inflammation.
Cytotoxic Lymphocytes(CTL) or CD8+ cells function:
recognize AG in invaded cells through MHC molecules and APC and destroy these cells.
Regulatory T lymphocytes function:
limit or down regulate activation of other lymphocytes and prevent autoimmunity(response to self)
Natural Killer Cells function
recognize changes on cells invaded by an antigen and destroy these cells. NK cells are part of Innate Immunity
