- Tissue-resident T cells in hepatitis B: A new target for cure?
A hallmark of chronic hepatitis B virus (HBV) infection is the functional impairment and depletion of antiviral T cells. In this issue of JEM, Pallett et al. identify a reservoir of functional HBV-specific T cells among liver-resident T cells.
- IL-2high tissue-resident T cells in the human liver: Sentinels for hepatotropic infection
Pallett et al. identify tissue-resident memory CD8 T cells compartmentalized in the healthy human liver that expand in controlled hepatotropic infection and can swiftly produce antiviral cytokines. This prototype may inform the development of liver-targeted T cell immunotherapy.
- pIgR and PECAM-1 bind to pneumococcal adhesins RrgA and PspC mediating bacterial brain invasion
Pneumococci are major causes of bacterial meningitis. Iovino et al. show that pneumococci invade the brain and pass the blood–brain barrier by interacting with the endothelial receptors pIgR and PECAM-1 recognizing the pneumococcal adhesin RrgA and PspC on the bacterial surface.
- Immune checkpoints on innate lymphoid cells
In this issue of JEM, Taylor et al. describe PD-1 as a critical negative regulator of group 2 innate lymphoid cells (ILC-2s). PD-1 intrinsically controls proliferation and cytokine production of both mouse and human ILC-2s. PD-1 signaling inhibits STAT5 phosphorylation and the removal of this brake by knocking down PD-1 expression or by using anti–PD-1 blocking antibodies, translated in vivo into better clearance of helminth worm infection in mice.
- Regression of apoptosis-resistant colorectal tumors by induction of necroptosis in mice
He et al. demonstrate that SMAC mimetic is efficient to target caspase-8–deficient colorectal cancer by induction of necroptosis. This study represents an attractive strategy for overcoming apoptosis resistance in colorectal cancer for the development of more effective personalized therapy.
- Self-reactive VH4-34–expressing IgG B cells recognize commensal bacteria
The human VH4-34 gene segment encodes intrinsically self-reactive antibodies that recognize I/i carbohydrates. Schickel et al. show that these self-reactive clones may represent an innate-like B cell population specialized in the containment of commensal bacteria when gut barriers are breached.
- IL-22BP dictates characteristics of Peyer’s patch follicle-associated epithelium for antigen uptake
IL-22 binding protein inhibits IL-22 signaling, which is important for intestinal homeostasis. Jinnohara et al. report that IL-22 binding protein is strongly expressed by Peyer’s patch dendritic cells and facilitates the M cell uptake of bacterial antigens into Peyer’s patches.
- Interleukin 4 promotes the development of ex-Foxp3 Th2 cells during immunity to intestinal helminths
Pelly et al. use novel mouse reporter systems to show that a proportion of Th2 cells develop from Foxp3-expressing cells in an IL-4–dependent manner, highlighting the potential to subvert T reg cell–mediated suppression in favor of type 2 immunity.
- RNF8 mediates histone H3 ubiquitylation and promotes glycolysis and tumorigenesis
Xia et al. show that EGF receptor activation results in the binding of the RNF8 forkhead-associated domain to pyruvate kinase M2-phosphorylated histone H3-T11, leading to histone H3 polyubiquitylation and degradation and subsequent gene expression for tumor cell glycolysis and proliferation.