Bacigaluppi and colleagues report that the accumulation of atypical mature and immature neutrophil subsets and a dysregulated emergency granulopoiesis response in aged mice and humans affect the outcome of stroke.

Bedoui and colleagues describe a sequential process of integration of innate and CD40-delivered signals in APCs, which optimizes their capacity to drive antiviral CD8⁺ T cell responses.

Linterman and colleagues examine germinal center formation in older individuals. They find that aged T_FH cells have dysregulated CXCR4 expression, which causes spatial mislocalization of these cells in germinal centers, impairing their ability to provide help to B cells and to promote antibody production.

In this Review, Künzli and Masopust provide updates on our understanding of the biology of memory CD4⁺ T cells as well as key technological advances that facilitate their characterization.

Linterman and colleagues examine germinal center formation in older individuals. They find that aged T_FH cells have dysregulated CXCR4 expression, which causes spatial mislocalization of these cells in germinal centers, impairing their ability to provide help to B cells and to promote antibody production.

De Martin, Ludewig and colleagues define the topology and molecular identity of human tonsillar stromal cells and show that PI16-expressing fibroblastic reticular cells shape subepithelial niches for efficient T cell activation and differentiation.

Pikor et al. show that a set of conserved, bidirectional cues exchanged between fibroblastic reticular cells and immune cells sustain B cell niches, which control humoral immune responses across mouse and human lymphoid organs.

Bacigaluppi and colleagues report that the accumulation of atypical mature and immature neutrophil subsets and a dysregulated emergency granulopoiesis response in aged mice and humans affect the outcome of stroke.

Bedoui and colleagues describe a sequential process of integration of innate and CD40-delivered signals in APCs, which optimizes their capacity to drive antiviral CD8⁺ T cell responses.

Single-cell and spatial analyses of conserved regulatory T (T_reg) cell-dependent transcriptional states of diverse accessory cell types in mouse and human lung cancer suggest rational T_reg cell targeting-based combination therapy for PD-1 blockade-resistant tumors.