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