Immunology - Principles Flashcards
Which cytokines are secreted by Th2s?
IL-4 - Promotes IgG and IgE class switching
IL-5 - Promotes IgA class switching; stimulates division and differentiation of eosinophils
IL-10 - Inhibits differentiation of T cell precursors into Th1s
Which cytokines are secreted by Th1s?
IL-2 - Provides the second signal for CTL activation
IFNy - Activates macrophages; inhibits differentiation of T cell precursors into Th2s
Which 2 signals activate naive T cells?
- Binding between antigen presented on MHC Class I and TCR
2. Binding between B7 on the APC and CD28 on the naive T cell
Which 2 signals activate B cells / class switching?
- Binding between foreign antigen presented on MHCII and the TCR
- Binding between CD40L on the APC and CD40 on the B cell
Which 2 signals activate CTLs?
- Binding between CD8 on CTL and MHC1 on virus-infected cell
- Binding of IL-2 from Th1s
Which cytokines are produced by Tregs?
IL-10 - Inhibits differentiation of Th1s
TGF-B - Inhibits differentiation of Th1s
IL-1
Endogenous pyrogen secreted by macrophages; causes fever and acute inflammation, activates endothelium to express adhesion molecules
IL-6
Endogenous pyrogen secreted by macrophages; causes fever and stimulates production of acute-phase proteins
IL-2
Secreted from all T cells; stimulates growth of helper, cytotoxic, and regulatory T cells
IL-2 transcription is down-regulated by cyclosporine (immunosuppressant); conversely, IL-2 is used in the treatment of certain cancers
CD28 / B7
CD28 on naive T cells binds B7 on antigen presenting cells; this interaction represents the second signal necessary for T cell interaction
CD40 / CD40L
CD40 on B cells binds CD40L on Th cells; this interaction activates the B cell to undergo activation and class switching
What cell surface markers are expressed by NK cells?
CD16 - Binds FC of IgG
CD56 - unique marker for NK
Which bacteria are catalase positive?
Pseudomonas Listeria Aspergillus Candida E. coli Staph aureus Serratia
Which complement components trigger histamine release?
C3a
C5a
Which vaccines are live attenuated?
MMR Polio (Sabin) Influenza (intranasal) Varicella Yellow fever
