01a cells of immune system, dwinell Flashcards
Two types of immunity
adaptive (acquired),
innate (natural) protection from birth
Define immunogen
Antigen that induces and immune response
define antigen
a molecule that binds to (is recognized by) antibody or T cells
-receiving preformed antibody
-rapid protection
-short duration (t1/2 for Ab= 3 weeks)
examples IgA in breast milk, humanized antibody (e.g. Remicade)
Passive immunity
exposure to a foreign antigen
slow protection
long duration-> memory lymphocytes
Examples: natural infection, vaccine (e.g. DTaP)
Active immunity
Specificity
Innate?
Adaptive?
Innate: Pattern-recognition receptors
- toll like receptors, nod like receptors
- limited diversity, non-clonal expression
Adaptive- Antigen receptors
- **T Cell receptor (TCR)
- **B cell receptor (BCR)
- Somatic Recombination leads to great diversity, clonal cells
Memory
Innate?
Adaptive?
innate: none
Adaptive- clones of lymphocytes remain in the body and will recognize and respond to antigen more rapidly than the first initiating exposure event
Microorganism is modified to decrease pathogenicity, limited growth after injection- What type of vaccination is this?
what type of response does it induce?
Pros and cons?
live attenuated
Cellular response (T Cells)
Pro: Strong, life-long immunity
Con: May revert to virulent form
Pathogen is inactivated (heat or chemically) but retains an immunologic epitope on surface- what type of vaccination is this?
What type of response?
Pros and cons?
Inactivated vaccine
Humoral response (B cells)
Pro: stable and safer than live
Con- weaker immunity- requires booster vaccine
Myeloid cells vs. lymphoid cells
Myeloid- erythrocytes megakaryocytes --> platelets Basophils Eosinophils Neutrophils (most abundant) Monocytes
Lymphoid (Thymus)
B Lymphocytes
T Lymphocytes
NK cells
___ circulates and enters tissue and differentiates into ___ to phagocytose foreign things
Large cell, lots of cytoplasm
Monocyte/ macrophage.
Large cell with lots of cytoplasm
most abundant circulating leukocyte, mediates earliest, most immediate phases of immunity. Lobed nucleus (3-5 lobes)
Neutrophil aka PMN (polymorphonuclear, polys)
___ arise from a hematopoietic precursor cell stimulated with the cytokine G-CSF
Neutrophils, aka pmn aka polys
motile phagocyte important in parasite infection and allergy.
granules contain heparin, hydrolytic enzymes.
stains red
Eosinophils, 1-3% of serum leukocyte population. Large granules that stain with acidic dyes.
non-phagocytic, circulate in blood, release pharmacologically active immune mediators (histamine…), release IL4 (Th2 cytokine)
acidic granules stain purple
basophils, less than 1% of circulating leukocyte population.
Granulocyte from bone marrow, emigrate/differentiate in tissue
granules contain heparin and histamine
important in allergic responses
Mast cells
Derived from the same bone marrow progenitor as monocytes, migrate and reside in tissues near site of microbe entry
primary function is Antigen Presenting Cell (transport and present microbial antigens to T lymphocytes in peripheral lymphoid tissues)
Dendritic cells
Distinguishing between T lyphocytes by:
cell surface molecules (CD##)
lots of nucleus, faint diffuse blue part = golgi.
Differentiates into plasma cell. Makes a lot of protein and secretes.
Effector B cells
Immunologic tissue primary (generative) lymphoid tissue - - secondary (peripheral) lymphoid tissue - - -
Bone marrow, thymus
lymph nodes, spleen, MALT/SALT (Peyers patch)
