Reviews & Analysis

Expressing chimeric antigen receptors (CARs) in macrophages has led to promising results in preclinical and clinical work. Now, induced pluripotent stem cells have been combined with a second-generation CAR to achieve macrophage rewiring and to broaden the applicability of the approach to solid malignancies.

T cells exist in many functional states, and dynamic transitions from one state to another affect the outcome of adoptive T cell therapy. FOXP1 and KLF2 are now identified as transcriptional regulators of the stemness of CD8⁺ CAR-T cells and the bifurcation of stem-like CD8⁺ CAR-T cells into effector and exhausted subsets, respectively.

We describe a system for introducing guide RNAs (gRNAs) to Cas9-expressing hematopoietic stem cells, which are used to generate mice with gene knockouts in the immune system. By using different gRNA-containing vectors and Cas9-expressing mice, we created systems for knockout of single genes or pairs of genes constitutively or inducibly.

BCG vaccination provides protection against unrelated viral infections. The vaccine induces protective integrated organ immunity through biphasic activation of innate and adaptive immune cells.

Mouse macrophages express specialized genes particular to the organs they inhabit, but whether the same applies in humans is unclear. In human peritoneal fluid, we identified many macrophage phenotypes, including two specialized macrophage types that corresponded to distinct mouse peritoneal macrophages. However, their abundances were markedly different between species.

In this Review, Netea and colleagues summarize the latest research that contributes to our understanding of the pathophysiology of sepsis, and how this contributes to a new treatment approach through personalized immunotherapy.

In this Review, the authors describe the mechanisms that account for the generation and immune recognition of neoantigens that are not derived from DNA mutations, with a special focus on relevance to cancer and autoimmunity.

The immune response to dengue virus infection is a well-coordinated balancing act. New research shows that an imbalanced response — driven partially by the productive infection of antigen-presenting cells — is associated with progression to severe disease.

Bantug and Hess discuss the metabolic interplay between tumor-resident cells and how the effect of metabolism-targeted anticancer strategies on non-transformed or immune cells in the tumor needs to be considered.

Here the authors review CAR T cell engineering and immunotherapy for cancer and juxtapose state-of-the-art developments with CAR NK cells as part of our Cancer Immunology series of Reviews.

We are in the midst of an explosion of multiomics and spatial data along with constant innovation of the tools used to study these data. In this Review article, as part of our Cancer Immunology and Immunotherapy series, the authors discuss these innovations and their application to study the tumor microenvironment.

Interleukin-27 (IL-27) is a pleiotropic cytokine known for its diverse immune regulatory properties. Although innate immune cells are considered the major cellular sources of IL-27, we found that gut regulatory T cells (T_reg cells) secrete IL-27 under inflammatory conditions, allowing them to selectively limit intestinal helper T17 cell (T_H17 cell) responses in various disease settings.

Cancer cells often overexpress CD47, which triggers the macrophage receptor SIRPα to elude anti-tumor immunity. We found that CD47 also suppresses phagocytosis by masking a pro-phagocytic ligand, SLAMF7, on tumor cells. We generated a first-in-class SLAMF7 antibody, which dissociated the CD47–SLAMF7 cis interaction, enabling anti-tumor immunity during SIRPα blockade.

After acute injury to skeletal muscle, an ‘early responder’ subtype of stromal cells rapidly produces an array of inflammatory mediators. Disruption of this response causes abnormal accumulation of several adaptive lymphocyte populations, a prolongation of inflammation, and an effect on tissue regeneration.

Regulatory T (T_reg) cells maintain the balance between immune protection and pathology. Research has now found that intestinal T_reg cells produce IL-27 to restrain T_H17 cell-mediated immune responses, effectively restricting autoimmune inflammation and limiting T cell responses to certain gut pathogens.

Determining the immune crosstalk between macrophages and NK cells in bronchioalveolar lavage fluid during SARS-CoV-2 infection in macaques identifies immunoregulatory properties of NK cells and their implications for viral persistence.

S100A8 and S100A9 are cytosolic alarmins with autocrine functions that facilitate neutrophil recruitment. Rapid, transient gasdermin-D pore formation is now shown to mediate secretion of these proteins in response to E-selectin without driving pyroptosis.

Two new studies in which apoE expression in mice is manipulated provide insights into the roles of microglial apoE in neurodegeneration.

Severe COVID-19 is marked by excessive inflammation that can persist after infection. The commensal yeast Candida albicans is now implicated in the acute and chronic immunopathology of COVID-19.

Hogan et al. identify a co-immunodominant influenza peptide presented in mice by MHC-E, a nonclassical class I molecule. Notably, the peptide derives from a 16-residue alternative reading frame translated by leaky ribosome scanning of the M1 mRNA and is recognized by conventional CD8⁺ T cells.