Immuno Q&A Flashcards
What are the three key events in the inflammatory response?
- Vasodilation and increased blood flow (calor, rubor, dolor)
- Increased vascular permeability (tumor)
- Infiltration of white blood cells (tumor)
What is the major amplification step of the complement cascade?
Formation of the C3 convertase
What is a Type I hypersensitivity disease?
Allergies and asthma
What is a Type II hypersensitivity disease?
disease caused by antibodies
e.g. immune thrombocytopenia
What is a Type III hypersensitivity disease?
disease caused by immune complexes (antigen/antibody complexes)
e.g. SLE/systemic lupus erythematosus
What is a Type IV hypersensitivity disease?
disease associated with “delayed hypersensitivity” or TMMI
e.g. PPD, nickel allergy
Give a snapshot summary of TC development
- HSC enters thymus. Notch signaling by DL-1/4 commits it to TC lineage: pre-T
- TCR , δ, β chains rearranged (requires RAG1 and RAG2)
- TCR associates with pre-Tα; first round of selection. If no recognition of self, dies: immature [CD4] single positive
- Remaining cells undergo α rearrangement (which excises region and commits TC to αβ receptor): double positive
- Positive selection: cells recognize MHC live via survival signal; don’t recognize, die
- Negative selection: in corticomedullary area; DC’s [screening for too-strong affinity] and TEC’s [screening for organ specific antigen] create central tolerance by deleting autoreactive TC’s
- Only then do cells commit to single positive lineage
Bacteroides fragilis (gut microbiota) does what?
Induces an anti-inflammatory response in the gut useful fro treating IBD
Induces anti-inflammatory Tregs in a mouse model which protect from EAE [mouse MS]
Name three challenges to xenotransplantation
(1) Preexisting anti-alpha1,3 galactosyltransferase (alpha 1,3 GT or alpha-gal) antibodies in human in response to gut microbiota
(2) insertion of DAF in alpha-gal KO pigs also only slows hyperacute rejection
(3) pig viruses
