MCB 4207 Study Guide - Fall 2018, Comprehensive Midterm Notes - Bacteria, Pathogen, Antibiotics
MCB 4207
MIDTERM EXAM
STUDY GUIDE
Fall 2018
08/23/2018 Class #2
- Innate Immunity:
o No memory
o First response
o Happens at surface:
▪ Epithelial surface
▪ Normal flora
▪ Biochemical defenses
o More complicated/specific:
▪ Pattern recognition receptors
▪ Phagocytosis
- Epithelial surfaces have different types and arrangements of cell which work as a barrier for bacteria
(challenge for bacteria to pass through).
- Mucosal epithelial make it harder for bacteria to get through.
o Tight junction between cells help keep bacteria outside.
- Antimicrobial peptides: cationic particles that destroy bacteria (biochemical defenses).
- Skin is very effective barrier; breach is usually through a cut or scratch, or through hair follicle.
- ***Defenses of the skin slide***
- 3 L’s:
o Lysozyme: present in secretions but also in phagocytes.
▪ Degrades peptidoglycan.
o Lactoperoxidase: contributes to oxidative type damage.
▪ Lacto: milk (present in breast milk).
▪ Peroxidase: oxidative function.
o Lactoferrin: keeps iron away from pathogens (then again, resistant bacteria have ways to find
iron).
- Ad…
o Acidic pH
o Defensins: antimicrobial peptides.
- Innate Immune System:
o Immediate
o Quick
o Relatively quick response
o No memory
o No B or T cells
o Progression from innate to adaptive response
o Weird to detect pathogen cell surface (not human cell surface).
▪ PAMP’s: bacterial
▪ PRR’s: o hua ells
• Detet pathoge ia PAMP’s ad determine course of action for destruction of
pathogen.
• Can be found on other cells that are not generally associated with the immune
system (help detect pathogen invasion).
• Enhance detection and destruction of pathogen.
E. TLR’s: differet TLR’s reogize differet PAMP’s
Typical response: release of inflammatory cytokines (induce
inflammation).
TLR 3, 7/8, 9, 10 are endosomal (inside cell) and mostly bound DNA and
RNA.
find more resources at oneclass.com
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• Cytokines:
o Interferon gamma: antiviral, macrophage activation.
o IL-2
o IL-4, 5, 10, 14
• Complement System:
o 3 activation pathways
o Activation leads to series of binding and cleaving components.
o MAC attack is not helpful with Gram (+) bacteria because of their THICK
peptidoglycan layer.
▪ Only effective in Gram (-).
▪ GM-CSF
- Phagocytes:
o Monocytes:
▪ Do’t do uh.
▪ Are precursors to macrophages and dendritic cells.
• Depedig o sigalig, the’ll ature to either oe.
o Macrophages:
▪ Kill pathogens by engulfment.
▪ eat till the lo up
▪ Pseudopods to reach.
o Dedriti ells D’s:
▪ Not everywhere (unlike macrophages).
• More localized.
▪ Not as potent in killing as macrophages.
▪ Presenting antigen to T and B cells.
o Neutrophils:
▪ Most abundant WBC.
▪ Circulating in blood.
▪ Programmed to be plentiful and ready to attack.
▪ More potent than macrophages (same mechanisms but more effective).
o NK cells:
▪ Do not engulf/take up pathogens.
▪ Reogize sik ells ad kill the.
• Reogize sik ells ased o:
o Lack of MHC I in surface.
o Attach to surface and release perforins and granzymes, which trigger
apoptosis.
- Septic Shock:
o Usually associated to Gram (-) bacteria.
o Excess of LPS (release of LPS).
▪ LPS binds LBP: LPS Binding Protein.
o Ctokie stor: heti release of tokies.
▪ Some produce coagulation: out of control coagulation (amongst other things).
o 3 C’s:
▪ Coagulation
▪ Complement
▪ Cytokines
find more resources at oneclass.com
find more resources at oneclass.com
Document Summary
Innate immunity: no memory, first response, happens at surface, epithelial surface, normal flora, biochemical defenses, more complicated/specific, pattern recognition receptors, phagocytosis. Epithelial surfaces have different types and arrangements of cell which work as a barrier for bacteria (challenge for bacteria to pass through). Mucosal epithelial make it harder for bacteria to get through: tight junction between cells help keep bacteria outside. Antimicrobial peptides: cationic particles that destroy bacteria (biochemical defenses). Skin is very effective barrier; breach is usually through a cut or scratch, or through hair follicle. A(cid:374)d : acidic ph, defensins: antimicrobial peptides. Typical response: release of inflammatory cytokines (induce inflammation). Tlr 3, 7/8, 9, 10 are endosomal (inside cell) and mostly bound dna and. Population is becoming more susceptible to pathogen infection. Only 4 companies dealing with antibiotic production. Nosocomial: hospital acquired infections; are becoming a problem. Postsurgical/wound infections: soldiers, for example, encounter these frequently. Normal human microbiota: bacteria produce certain enzymes that aid us in digesting/degrading food.
