Myor/ABF-1 mRNA [corrected] Expression Marks Follicular Helper T Cells but Is Dispensable for Tfh Cell Differentiation and Function In Vivo.

Follicular T helper cells (Tfh) are crucial for effective antibody responses and long term T cell-dependent humoral immunity. Although many studies are devoted to this novel T helper cell population, the molecular mechanisms governing Tfh cell differentiation have yet to be characterized. MyoR/ABF-1 is a basic helix-loop-helix transcription factor that plays a role in the differentiation of the skeletal muscle and Hodgkin lymphoma.

The capacity of Th2 lymphocytes to deliver B-cell help requires expression of the transcription factor STAT3.

CD4(+) T-cell help for B cells is crucial for effective Ab responses. Although follicular T helper (Tfh) cells have emerged as the main providers of T-cell help to B lymphocytes during the germinal center reaction, much less is known about the helper capacities of other effector CD4(+) T cells. The purpose of the present study was to evaluate the acquisition of B-cell help capacity of canonically derived T helper 2 (Th2) cells, a Th-cell subset originally considered responsible for B-cell help in vivo.

New role for hPar-1 kinases EMK and C-TAK1 in regulating localization and activity of class IIa histone deacetylases.

Class IIa histone deacetylases (HDACs) are found both in the cytoplasm and in the nucleus where they repress genes involved in several major developmental programs. In response to specific signals, the repressive activity of class IIa HDACs is neutralized through their phosphorylation on multiple N-terminal serine residues and 14-3-3-mediated nuclear exclusion. Here, we demonstrate that class IIa HDACs are subjected to signal-independent nuclear export that relies on their constitutive phosphorylation.