HEB Restrains Effector Gene Expression during Early CD8⁺ Memory Precursor T Cell Differentiation.

Area of Science:

• Immunology
• Molecular Biology
• T cell differentiation

Background:

• Memory T cells are vital for long-term adaptive immunity.
• The molecular mechanisms governing T cell lineage choice after TCR signaling remain unclear.
• The role of transcription factor HEB in peripheral T cell differentiation is poorly understood.

Purpose of the Study:

• To investigate the function of HEB in the differentiation of CD8 memory T cell precursors.
• To elucidate the molecular mechanisms by which HEB regulates early T cell differentiation and effector gene expression.

Main Methods:

• Induction of TCR signaling in CD8 T cells from HEB-deficient and wild-type mice.
• Analysis of T cell differentiation under memory-polarizing conditions or inflammation.
• Transcriptomic analysis to identify gene expression changes.
• Assessment of T cell function following acute viral infection in HEB conditional knockout (cKO) mice.

Main Results:

• HEB-deficient CD8 T cells exhibited accelerated differentiation compared to wild-type cells.
• Transcriptomic analysis revealed aberrant upregulation of immune response genes and decreased stemness-associated genes in HEB-deficient cells.
• HEB-deficient mice showed enhanced memory precursor cell formation and increased effector functionality after viral infection.

Conclusions:

• HEB is a key regulator in the gene regulatory networks controlling early CD8 memory T cell differentiation.
• Loss of HEB leads to increased TCR signal strength and a loss of stemness signatures in naïve CD8 T cells.
• HEB plays a critical role in promoting the development of immune memory.