Following Their Activation, Naive CD4 T Cells Differentiate into One $\gamma$

question 37

Multiple Choice

Following their activation, naive CD4 T cells differentiate into one of several subsets of effector T cells. This developmental choice is determined by which specific cytokines the T cells are exposed to during their activation; in turn, the cytokines that are produced will reflect the nature of the infecting pathogen. In order for this system to be flexible enough to produce all five effector CD4 subsets (T_H1, T_H2, T_H17, T_FH, and iT_reg) :

• A) Each naive CD4 T cell must already express one of the lineage-specific transcription factors (i.e., T-bet, GATA-3, etc.).
• B) Each naive CD4 T cell must express all of the STAT proteins.
• C) Each naive CD4 T cell must express only a single STAT protein (i.e., STAT1 or STAT6 or STAT3, etc.).
• D) Each naive CD4 T cell must already express low levels of the subset specific cytokines (i.e., IFN\(\gamma\), IL-4, IL-17, etc.).
• E) Each naive CD4 T cell must express all of the lineage-specific transcription factors (i.e., T-bet, GATA-3, etc.).

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Definitions:

Yield To Maturity

The total return anticipated on a bond if held until it matures, accounting for its current market price, interest payments, and eventual repayment of principal.

Required Rate Of Return

The minimum acceptable rate of return considering both its risk and the returns available on other investments.

Bond Yields

The amount of return an investor realizes on a bond, calculated as the percentage of the bond's annual interest payments relative to its market price.

Yield To Call

The return a bondholder gets if the bond is held until the call date, which is before the bond's actual maturity date.