Test 2: Inflammation Flashcards
What are 4 effects of inflammation?
- increase in temp= calor
- redness= rubor
- swelling= tumor
- pain= dolor
What are the mediators in response to bacterial infection?
histamine, PG, TNFa
What do mediators do in acute inflammatory response?
mediators increased capillary permeability leading to influx of plasma proteins and phagocytic cells, contributing to swelling, redness, heat and pain
How are cytokines produced and by what?
Cytokines produced by innate cells upon interaction with infectious agents and activate/mobilize other cells
What are the cytokine effects on vascular endothelium?
endothelial wall gains new adhesion proteins specific for interactions with leukocytes (ex: selecting, integrin ligands)
What activate the complement and opsonization in the liver?
TNFa, IL1, IL6
What cause decreased viral and bacterial replication in hypothalamus, fat, and muscle?
IL1, TNFa by increasing body temperature which inhibits enzyme activity involved in protein synthesis and DNA/RNA replication
What is the first step of leukocytes getting recruited to sites of infection?
I- Rolling
up regulation of adhesion molecules (selection, integrins)
- selectins roll on wall and crawl through vessel walls
What is the second step of recruitment of leukocytes?
II- integrin activation by chemokine
What is the third step of recruitment of leukocytes?
III- stable adhesion
What is the fourth step of recruitment of leukocytes?
IV- Migration through endothelium
What are the liver plasma proteins?
SAP, CRP, MBL
- all function as opsonin which target microbes for phagocytosis
What are molecules coating microbe surface to target for phagocytosis?
opsonin
What is the process of marking microbe for ingestion?
opsonization
What is the order of opsonins bind to microbe and phagocyte receptor?
opsonins simultaneously bind to microbe and phagocyte receptor which then activate complement
How does the activation of complement system work?
all paths lead to cleave of C3 by C3 convertase into C3b=opsonin and C3a=anaphylatoxin
What is C3a and C3b for?
C3b=opsonin which is for opsoninization and phagocytosis and C3a=anaphylatoxin which is for inflammation
What are the local inflammatory responses that C3a and C3b induce?
- increased vascular permeability
- increased microbicidal activity
What do phagocytes do?
- ingest microbes which then involves killing of microbes and processing of antigens
- definition: process of ingestion of opsonin-coated or receptor-bound microbes
What is the oxidative or respiratory burst?
generation of O2 and reactive oxygen species that are toxic for ingested microbes
- how microbes are killed once phagocytosed in phagolysosome
What does pus tell us in the oral cavity?
dying neutrophil
How do neutrophil extracellular traps work?
- high local concentration of antimicrobial components that kill microbes extracellulary
How do innate cells mediate inflammation identified by swelling, redness, heat, and pain upon infection?
they produce molecules that recruit cells/proteins to the site
How do cells at site of infection alert other innate cells of the immune response?
cytokines attract and activate cells or induce cellular processes
What cells are found at inflamed site?
neutrophils and monocytes
Describe the 1 step of recruitment of leukocytes (rolling step)
- macrophages responding to toll like receptor by binding to a receptor on the surface of the bacteria
- cytokines like TNF and IL-1 will be produced
- this will stimulate endothelial cells to up regulate adhesion molecules such as selection and integrin that binds with low affinity
- LFA-1 binds to ICAM-1 while VLA-4 binds to VCAM1
What is the classical pathway for activating complement?
CRP-SAP
What is the lectin pathway for activating complement?
MBL
Of the cells listed, which kills microbes and which processes antigens?
a. neutrophil
b. macrophage
c. dendritic cell
neutrophil and macrophage= kill microbes
dendritic cell= process antigen
Other than the phagocyte oxidase system, what is another free radical generating system to kill an ingested microbe?
generation of NO
- No and reactive oxygen species together can generate reactive peroxynitrate radicals that are even more toxic
