HTHSCI 1H06 Lecture 1: Immunology_Cram
2 May 2018
School
Department
Course
Professor
Immunology
• 3 stages = intrinsic, innate and adaptive
Intrinsic: already existing within body
• Mechanical – sneezing, coughing, urination, skin
• Chemical – low pH to kill bacteria, lysozyme
• Microbiological – commensal flora, bacteria already on surface to block
binding sites!
• Physiological – high temperature ie. Fever
Innate: difference between immediate/resident and early induced?
• Immediate (0-4 hours) = already residing in the cells ie. The
macrophages, the complements vs. Early Induced (4-96 hours) = need
to be induced (not already there), so the blood borne stuff like
neutrophils + more macrophages
1. Complements: precursor (C3) proteins floating in body, waiting to be
activated (C3a,b)
a. Activated by lectin mannose, as bacteria have a different type;
antibody-pathogen binding; pathogens themselves whom have
surface enzymes that cleave the complements
b. Functions:
i. Opsonization (works as second line of defense with TLRs)
ii. MAC – membrane attack complex, forms transmembrane
channels which disrupt the pathogenic cell and kills it
iii. Inflammation
• 4 signs – redness (rubor), swelling (tumor), pain (dolor) and
heat (calor)
2. Resident phagocytes
a. Macrophages and dendritic are within the tissue already –
phagocytosis, where they engulf the bacteria and fuse with the
lysosome = phagolysosome
i. Macrophages differentiate from precursor monocytes
(dendritic cells differentiate from them too), and are long-
living
b. Neutrophils are in the blood, and are recruited later on by cytokines
i. Specific cytokine is IL-8 or CXCL8 – also note, cytokines are
produced by macrophages
ii. Neutrophils are most present in the blood and contain toxic
granules
3. Inflammation activation
a. PRR (pathogen recognizing receptors, like TLRs) recognize PAMPs
(pathogen associating molecular patterns)
i. TLR 1/2/6 recognize gram + bacteria
find more resources at oneclass.com
find more resources at oneclass.com
Document Summary
Immunology: 3 stages = intrinsic, innate and adaptive. Intrinsic: already existing within body: mechanical sneezing, coughing, urination, skin, chemical low ph to kill bacteria, lysozyme, microbiological commensal flora, bacteria already on surface to block, physiological high temperature ie. fever. Innate: difference between immediate/resident and early induced? binding sites! Immediate (0-4 hours) = already residing in the cells ie. the macrophages, the complements vs. Adaptive: when apcs (antigen-presenting cells) interact with our t-cells. Apcs: antigen-presenting cells: tlr 3 recognize double stranded rna, like viruses. T-cells: 2 types: cd8 and cd4 interact with b-cells, t1 helper turns on macrophages, t1/2 helper turns on b-cells, divides rapidly + differentiates into effector t-cells. B-cells: from cd4 t-cells, activated, and then become plasma (shorter duration, they make antibodies) + memory (help with the secondary response being faster: rapidly divides (through help of t-cell growth factors)
