At early timepoints following an infection, examination of lymph node CD4 T cells responding to the pathogen would show a heterogeneous population of cells representing several different effector lineages. Likewise, the cytokines produced by these cells would include IFN$\gamma$, IL-4, and possibly others. However, approximately one week later at the peak of the T cell response, the pathogen-specific CD4 T cell population would be largely homogeneous in their production of a single effector subset cytokine profile. This change comes about due to:
A) Death of the CD4 T cells making the non-protective cytokines
B) Increased proliferation of CD4 T cells making protective cytokines
C) Enhanced differentiation of newly activated CD4 T cells into one effector subset
D) Inhibition of antigen-presenting cells by CD4 T cell-derived cytokines
E) Impaired proliferation of effector CD4 T cells by IFN$\gamma$

Question

Quizplus · Accepted Answer

As the T cell response progresses, newly activated CD4 T cells differentiate into one effector subset, allowing for a more focused and effective immune response to the pathogen. This is driven by the T cell receptor signaling pathways and cytokine signals received by the T cells.

At Early Timepoints Following an Infection, Examination of Lymph Node γ\gammaγ

At Early Timepoints Following an Infection, Examination of Lymph Node $\gamma$