Volume 16 Issue 11, November 2015

Mitochondria can contribute to an increase in the amount of phagosomal reactive oxygen species and thereby promote the effective killing of bacteria. Study of mice deficient in Mst1 and Mst2 reveals a role for these kinases in recruiting mitochondria to phagosomes.

The T_H17 subset of helper T cells drives emphysema in smokers, but how these cells are elicited remains unknown. A study now links the microRNA miR-22 and the histone deacetylase HDAC4 to regulation of the activation of antigen-presenting cells after exposure to smoke.

The RNA endonuclease Drosha is required for myelopoiesis by its direct cleavage of stem-loop structures in mRNAs encoding Myl9 and Todr1.

While most studies of T lymphocytes have focused on peptide-MHC-reactive T cells, many other types of T cells do not fit this paradigm. Here Godfrey et al. review the immunology of such unconventional T cells.

The transcriptional control of lineage commitment to various ILC subsets is incompletely understood. Yokoyama and colleagues show that Runx3 is essential for the normal development of ILC1 and ILC3 cells but not ILC2 cells.

The enzyme Drosha is associated with the biogenesis of microRNA. Chong and colleagues identify a non- microRNA function for Drosha in dendritic cell development.

Mitochondria must be juxtaposed to phagosomes to supply reactive oxygen species for effective killing of microbes. Zhou and colleagues demonstrate that the kinases Mst1 and Mst2 are important for controlling this redistribution of mitochondria.

To date, structural analysis has demonstrated a highly consistent binding pattern of the TCR to the MHC molecule. Rossjohn and colleagues reveal the first structures of two human T_reg cell TCRs and show that they bind with a reversed polarity to the MHC.

Chatila and colleagues demonstrate a critical role for Notch canonical and non-canonical signaling in controlling peripheral T_reg cell function.

The metabolic requirements of T cells vary according to their functional state. Matarese and colleagues show that the most functionally active human regulatory T cells are highly glycolytic and that this directly controls expression of a distinct splice variant of the transcription factor Foxp3.

Smoking can lead to emphysema. Corry and colleagues show that smoke and carbon black particles induce the microRNA miR-22 as a mediator that suppresses expression of the histone deacetylase HDAC4 and thereby promotes a chronic T_H17 cell–dependent inflammatory response.

Sumoylation regulates many cellular processes, but its role in TCR signaling remains unknown. Li and colleagues show that sumoylation of the kinase PKC-θ is required for the assembly of a mature immunological synapse.