Microbial Recognition and Responses in Innate Flashcards
What is a PDC?
plasmacytoid dendritic cells. This is a sentinel tissue cell that detects viruses and will release Type 1 Interferons
What is Type 1 IFN (type 1 interferons)
these are cytokines that is released via innate signaling and will induce an anti-viral state
What happens during the antiviral state?
A virus will infect a cell and is taken up by the PDC via receptors (TLR) that are located in endosomes inside the cell. Phosphorylation of the transcription factor. This allows the Type 1 INF gene to be transcribed. the Type 1 INF cytokine is released by the PDC. These cytokines will bind to receptors of infected cells and create an “antiviral state”
what is a PAMP
molecules that are common on pathogens, but not vertebrate cells (these are recognized by TLR on dendritic cells)
What is a PRR
Pattern Recognition Receptors (receptors that recognize microbial PAMPS)
What is a TLR
Toll Like Receptor (a type of PRR). These can be located on the surface of cells or inside the endosomes of cells.
Where is the TLR located on a cell if the outcome is an immune response where pus is made?
Located on the cell surface and recognizes gram+ and gram- bacteria PAMPS
Where is the TLR located on a cell if the outcome is the anti-viral state?
The TLR is in the endosome and it recognizes ssRNA, dsRNA or dsDNA from viruses.
How does signaling happen when a tissue sentinel cells TLR recognizes a bacteria PAMP?
the TLR binds to the PAMP. NF-KB (with inhibitor) gets rid of the inhibitor. This allows the NF-KB to transcribe the gene to make TNF or IL-1 cytokines….which then are released and create immune response (neutrophils come out of blood)
What is an Aggultinin?
(Lectins) Mannose (sugar) binding antibody that will cause complement activation or clumping of microbes.
Opsonization
when an antibody or C3B fragment coat a microbe. This allows a phagocyte to recognize and ingest it.
Alternate/spontaneous pathway for C3 protein cleaving
microbe surfaces causes C3 to spontaneously cleave it C3b and C3a
Classical pathway for C3 protein cleaving
C1Q (complement protein) binds to IgM and this causes the cleaving of C3b and C3a
Lectin pathway for C3 protein cleaving
lectins bind to sugars on microbes and then this causes the cleaving of C3 into C3b and C3a
Original treatment for hepatitis C virus
Type 1 INF (to produce the antiviral state)
