How Senescence Changes Cell Function

Senescence is a cellular state involving long-term growth arrest and altered cell function. Recent studies are examining not only whether senescence occurs, but also how senescent cells affect surrounding tissues. In B-cell lymphoma, treatment-induced senescence enhanced antigen presentation, making cancer cells easier for T cells to recognize and eliminate. In human neural models, UPRmt, a response to abnormal protein accumulation in mitochondria, behaved differently. Although considered protective in simple organisms, sustained UPRmt induced a senescence-like inflammatory state in microglia and impaired neuronal communication and cellular clearance functions. Together, these studies show that senescence-associated changes can support tumor immune control or disrupt neural homeostasis. Senescence should therefore be assessed through both conventional markers and changes in cell function and cell-to-cell interactions.

Senescence-associated lineage-aberrant plasticity evokes T-cell-mediated tumor control
(Belenki et al., Nature Communications, 2025)

Summary: 
In this study, human and murine B-cell lymphoma models were used to examine how therapy-induced senescence alters cancer-cell function. Senescent lymphoma cells acquired dendritic- and macrophage-like antigen-presentation features, activated cytotoxic T cells, and became more susceptible to T-cell-mediated killing, supporting tumor control.

Highlighted technique: 
To determine whether therapy-induced senescence produced an immunogenic cell state, SA-β-gal staining and proliferation tracking were combined with flow cytometry for myeloid and antigen-presentation markers, antigen-processing assays, and T-cell co-culture followed by measurements of T-cell activation and lymphoma-cell viability.

Assessing cellular states requires methods suited to the experimental objective. For example, SA-β-gal activity can be evaluated by multiplex imaging, flow cytometry, tissue imaging, or plate reader-based assays to obtain different types of information.
Through this link, first-time users can apply for a free sample of a kit that detects SA-β-gal activity in both live and fixed cells, while supplies last. Staining takes 30 minutes, and samples can be analyzed by fluorescence microscopy or flow cytometry. 

The mitochondrial unfolded protein response in human microglia disrupts neuronal–glial communication and promotes senescence 
(Perez et al., Nature Neuroscience, 2026)

Summary: 
In this study, UPRmt was examined in human iPSC-derived neural cultures and microglia-containing brain organoids. UPRmt is considered protective in simple organisms, but here it drove microglial metabolic remodeling and a senescence-like inflammatory state, impairing neuronal-glial communication, synaptic pruning, autophagy-lysosome function, and abnormal protein clearance.

Highlighted technique: 
To evaluate senescence and organelle dysfunction after mitochondrial proteotoxic stress in human iPSC-derived microglia, SA-β-gal staining was combined with fluorescence-based assessment of mitochondrial membrane potential, autophagic flux, lysosomal function, and abnormal protein clearance using microscopy and immunoblotting.

Combining SA-β-gal activity with mitochondrial membrane potential, autophagic flux, and lysosomal function helps assess both senescence-like changes and the associated decline in cell function.