What is immunity?
Lymphoid cells
B lymphocytes, T lymphocytes, Natural killer cells
Myeloid cells
Macrophage, Dendritic cells, Mast cells, Granulocytes (Neutrophil, Eosinophil, Basophil)
Innate defenses (natural, native)
Surface barriers(skin, mucous membranes), Internal Defenses (phags, NK cells, inflammation, fever, antimicrobe proteins)
T lymphocyte lineage starts in
Thymus
Examples of Mucosal-associated lymphatic tissue (malt)
Tonsils, peyers patches in intestine, appendix
antigen-presenting cells function
display microbial and self peptides on major histocompatibility complex (MHC) molecules
Mast cell (granulocytes)
effector cell involved in allergic rxns
naive lymphocyte are
immunologicaly inexperienced/ immunocompetent
Innate immune response triggers the
inflammatory response
Neutrophil (granulocytes)
ingest and destroy
Granulocytes
involved in inflammation and hypersensitvity
Eosinophil (granulocytes)
killing extracellular pathogens
3 adaptive immunity strategies
- Block infections and eliminate extracellular microbes (B lymphocyte) - Activate macrophages to kill phagocytosed microbes (Helper T lymohocyte) -Kill infected cells and eliminate reservoirs of infection (Cytotoxic T lymphocyte)
B cells
- CD21 - antigen recognition and presentation -involved in adaptive immunity; extracellular microbes
Natural Killer cells
-CD16 -cell-mediated killing -involved in innate immunity; infected cells
T cells
-CD4 or CD8 -antigen recognition and mediates killing -involved in adaptive immunity; intracellular microbes
Professional Anitgen presenting cells
-DC, MQ, B cells -found at the common portals of microbial entry -DC and MQ have the ability to activate naive T-cells
Innate immunity characteristics
-non-specific -first line of defense -fast (minutes) -recognition of common molecular structures -limited diversity -no memory -primitive -invertebrates
adaptive immunity characteristics
-specific -second line of defense -slow (days) -recognition of specific microbial antigens -high diversity -immunologic memory -recently evolved -vertebrates
How the inflammatory response protects the body
-triggered whenever body tissues are injured or infected -prevents the spread of damaging agents -disposes of cell debris and pathogens -sets the stage for repair
B lymphocyte lineage starts in
Bone marrow
Anatomic defect in thymus development results in
Digeroge syndrome and Nezelof syndrome
Adaptive defenses (specific, acquired)
Humoral immunity (B cells), Cellular immunity (T cells)
Basophil (granulocytes)
allergic rxns and worm infections
Dendritic cell
antigen presenting cell involved in initiating adaptive immunity
Monocyte (Blood)/ Macrophage (tissue)
phagocytic cell involved in innate and adaptive immunity
All blood cell types develop from a common
pluripotent hematopoietic stem cell
Lymphocytes mature in the
primary lymphoid organs (thymus and bone marrow)
Function of Mucosal-associated lymphatic tissue (malt)
protects the digestive and respiratory systems from foreign invasion
Immune responses are initiated in
secondary (peripheral) lymphoid organs
