Imunology lecture 1_cells of the immune system Flashcards
List the three anatomic barriers to infection
Epitherlial tissue
Mucus
Cilia
List the three chemical barriers to infection
Antimicrobial enzymes (lysosomes that can digest bactiera cell wall found in tears and saliva)
Defensins (host peptides that can directly lyse bacteria cell membrane)
Acids (ie stomach acid)
List the three types of lymphocytes
B cells, T cells, NK cells,
List the four types of granulocytes
Neutrophil, Eosiniphil, Basophil, Mast cell
What cells compose the innate immune response
all four types of granulocytes, NK cells
What cells are part of both the innate and adaptive imune response?
Macrophages and dendritic cells
What cells are part of the adaptive immune response
B cells and t cells
Where do b cells mature
the bone marrow
What is the role of B cells in the immune response
to produce anti bodies
What happens to an activate B cell
to can either become a plama cell which is short lived and activly secrets anti bodies or it can become a memory cell, a long lived cell that prevents against reinfection
where do T cells mature
in the thymus
What are the three kinds of T cells and their roles
- Cytotoxic T cells (CD 8) induce cell death via direct cell contact
- Helper T cell (CD 4) produces cytokines to modulate immune response
- Regulatory T cell suppress immune response
What are activated T cells
they are effector and or memory cells
Describe how NK cells kill target cell
NK cells deposite Perforin onto the cell membrane of the target cell. The perforin polymerizes and formes a channel for granzymes to enter through. Granzymes trigger apoptosis of the target cell.
LIst three important things about the NK cell response
1) despite being lympocytes, NK cells are considered to be part of the innate immune system because the have no antigen specificity and are therefore not addaptive.
2) they are important for early viral infection before the adaptive immune system can mounta response
3) NK response is based pn the balance of activiating and inhibitory signals it receives. (I believe this means that it could attack any cell including healthy host cells.
What 4 cells are phagocytes
Macrophages, dendritic cells, neutrophils, eosinophils (eosinophils also cause degranulation)
How do phagocytes work
Phagocytes identify material to ingest by using pattern recognition receptors
What two kinds of cells do monocytes differentiate into?
Macrophages and dendritic cells
Where are monocytes found? How long do the circulate
monocytes are found in the blood and will circulate for a day before differentiating
What function does a monocyte have before differentiation
Monocyte functions include Antigen presentation, phagocytosis, and cytokine production
What is the shape of a monocyte nucleus
C or horse shoe shaped
What are macrophages functions
Primary function is phagocytosis but can include antigen presentation, inflamation, and cytokine production
What is the purpose of cytokines?
To regulate the immune response
What cells produce the majority of cytokines
Macrophages (to regulate innate immune response) and Helper T cells (to regulate the adaptive immune response)
What is the primary role of dendritic cells?
to present pathognes to activated T cells
Describe neutophils
They are the first responders in cell mediated immunity. THey can participate in phygocytosis, degranulation, and Neutrophil extra cellular traps
Describe the importance of banded, segmented, and hyper (more than 5) segmented nuclei of neutrophils
Banded - horse shoe shaped indicates immature neutrophil
Segmented- indicates matture neutorphil (more immature than mature neutorphil in blood can indicate infection)
Hypersegmented- indicates a B12/folate deficency
Describe the mechanisium of Eosinophils
Primary mechanism is degranulation (as with parasites) secondary is phagpcytosis.
What color are eosinophils with H&E stain
Granules stain red
What is the primary mechanism of Basophils
degranulation. Their granules contain histamine and heparin
What color are basophils with H&E stain
granules stain purple
Where do basophils exist in the body
They circulate through the blood
What is the mechanisium of mast cells
Degranulation. they contain the same granules as basophils
where are mast cells found?
In tissues
