immunology Flashcards
name the types of non specific immune cells
phagocytic cells, monocytes, neutrophils, macrophages, natural killer cells
difference between monocytes and macrophages?
monocytes: circulate in blood, eat invaders
macrophages: in tissues . eat everything that is not self
types of immune cells / new blood from bone marrow
RBC’s, neutrophils, monocytes etc
what do neutrophils do?
consume invaders. Die after attack. Accumulation of pus = dead neutrophils. Release fibrous traps. Kill w/ “NET’s”
what do natural killer cells do?
Kill EVERYONE. Punch holes in bad cells 2 kill. (perforin)
note that they are their own cell type
stimulated by cytokines
Interferons
proteins secreted by virally infected self. It’s a signal saying “SAVE YOURSELVES IM INFECTED!” causes other cells to alter their metabolism; reduces transcription of local cells, shorten ½ life of RNA.
pyrogens
fever inducing signal
why is a slight fever good for the body when there’s an invader?
sequester iron in liver - unavailable to microorganisms
high temp slows bacterial growth
increases activity of phagocytic cells
Complement System- how is it different from natural killer cells?
both punch holes and both are stimulated by cytokines, but the complement system is a bunch of peptides led by a peptide called C3 that assemble into MAC (membrane attack complex) versus natural killer cells which are actual cells
specific immune cells
refer to t cells and b cells only!
Mast cells and their consequence:
release histamines. Results:
• Erythema (redness), edema.
• Neutrophils rush over. Jump on the splinter, out of blood stream, : process is called “diapedesis” cells leaving circulation to enter the tissue spaces.
• Neutrophils jump on their NETS , then die, and you get pus
first line of defense
unbroken skin
All openings are protected by some mechanism:
respiratory system, macrophages
A. urogenital tract system: protect with acidity (why u drink cranberry juice)
B. digestive tract: lymphoid centers, Peyer’s Patches
C. tonsils- act as lymphoid barrier
o pharyngeal tonsils-adenoids, palatine tonsils, lingual tonsils
second line of defense
Cellular proteins and other mechanisms A. lymphatic system B. Immune Cells C. Non specific immune cells D. other (fevers, interferons etc)
third line of defense
Active/adaptive immunity
antibodies, T-cells (4 kinds!)
Antibody:
proteins with binding sites for specific targets. Binding site = antigen.
• Clusters of Differentiation aka “CD” markers
• markers on surface of immune cells
o >100 known. CD4, CD8. Most important.
o Way to tell populations of cells apart from each other
Immune Cells
Have immune receptors on them to recognize invaders
ex: lymphocytes, T cells, B-lymphocytes
T-lymphocytes- whats special about their education
“educated” in the thymus. Selected for those that do not recognize ‘self.’