Volume 19 Issue 1, January 2018

Damaged mitochondria are targeted for mitophagy by the Pink–Parkin ubiquitin pathway. The mitochondrial ATPase Atad3a prevents aberrant activation of Pink and protects hematopoietic stem cells.

A new ‘alarm mechanism’ of the innate immune system that signals the presence of nuclear viruses involves the sensing of host 5S rRNA by RIG-I.

A previously unknown role is identified for a pathway that involves major histocompatibility complex class I and an inhibitory receptor, LILRB1, that regulates the phagocytosis of cancer cells by macrophages and contributes to resistance directed against the signal-regulatory protein CD47.

Single-cell sequencing identifies novel subtypes of intestinal epithelial cells and their molecular signatures, which reveals new principles for gut homeostasis and the response to infection.

Nikolich-Žugich reviews recent developments in our understanding of age-related changes affecting key components of immunity

Emerging viral diseases present a huge and increasingly important global threat to public health systems. Graham and Sullivan discuss the challenges presented by emerging viral diseases and discuss how innovations in technology and policy can address this threat.

The survival of hematopoietic stem cells requires tight regulation of mitophagy. Lin and colleagues show that Atad3a regulates mitophagy in these cells by sequestering the mitophagy initiator Pink1 and directing its import via the mitochondrial Tom40–Tim23 complex.

Cao and colleagues identify the E3 ubiquitin ligase RNF2 as an inhibitor of interferon-dependent antiviral responses that acts by promoting the K33-linked polyubiquitination of STAT1 and its disassociation from DNA.

RIG-I is a cytosolic RNA sensor. Gack and colleagues show that herpesviruses, duplex DNA viruses, also activate RIG-I by inducing cytoplasmic translocation and unmasking of an endogenous host 5S ribosomal pseudogene RNA, RNA5SP141.

Plasmacytoid dendritic cells (pDCs) are known for their copious IFN-I production. Soumelis and colleagues show that functionally and transcriptomically distinct human pDC populations can be generated from a single microbial or cytokine stimulus.

Host cells display ‘don’t eat me’ signals to protect themselves from phagocytosis. Maute and colleagues identify a novel ‘don’t eat me’ system based on recognition of MHC class I by the phagocyte-expressed inhibitory molecule LILRB1.

Vyas and colleagues show that a continuum of hemopoietic progenitor cells from human cord blood execute lymphoid and myeloid differentiation.