Webb, L. M. | bioRxiv Science

bioRxiv2026

Antigen accumulation in the B cell follicle is impaired in aged mice

Vaccine responses are impaired in aged mice and older people. An essential early step in mounting successful responses to vaccines is the delivery of antigens from the site of injection to the draining lymph node. This study tested the hypothesis that particle drainage to the lymph node is impaired in older mice after intramuscular injection. We observed fewer 20nm nanoparticles in the B cell follicle of the draining lymph node in aged mice after intramuscular injection. However, there was no significant difference in the abundance of larger 1000nm particles in the lymph nodes of aged mice, which are typically transported to the lymph node by antigen presenting cells. This data suggests that access of smaller antigens to the B cell follicle is impaired in ageing and may have implications for the initiation of T and B cell responses after vaccination.

immunology↗

bioRxiv2025

Neuronal recordings in head-fixed and freely-moving mole-rats

Mole-rats are subterranean rodents that have evolved remarkable sensory adaptations to life in underground tunnel systems, yet their neural mechanisms remain largely unexplored. Here, we present a protocol for in vivo electrophysiological recordings in awake, head-fixed, and freely moving African mole-rats (Fukomys anselli/micklemi), overcoming unique challenges of studying the neurobiology of subterranean species. For example, we find that mole-rat brain physiology impacts survival after surgeries, with higher carbon dioxide concentrations required for recovery compared to other rodents, likely due to a mutation in the chloride-potassium symporter KCC2. Having addressed the challenges, we used tetrodes and Neuropixels probes to record single-unit activity and local field potentials (LFP) across several cortical and subcortical regions for several weeks. We observed single units responsive to auditory and visual stimuli in the superior colliculus, and hippocampal recordings in freely moving mole-rats revealed prominent theta rhythms at frequencies lower than those observed in any other rodent species to date. Finally, we performed integrated three-dimensional and two-dimensional probe-track analysis within the same brain using tissue clearing, light sheet imaging, rehydration, and vibratome sectioning, and we present a newly developed stereotaxic brain atlas for implantation and histological alignment. The established methodology will guide future studies in comparative rodent neurobiology, providing further insights into neurobiological adaptations to subterranean environments. Given their phylogenetic and ecological similarities, we expect our protocols to be transferable to other subterranean species, including the widely studied naked mole-rat (Heterocephalus glaber). HighlightsO_LIProtocols for chronic and acute electrode implantations in mole-rats C_LIO_LIStereotaxic brain atlas for the Ansells mole-rat (https://doi.org/10.17617/3.UNDKRO) C_LIO_LINeuropixels and tetrode single-unit recordings in head-fixed and freely moving mole-rats C_LIO_LIIntegrated 3D (tissue clearing) and 2D (histology) probe-track analysis within the same brain C_LIO_LIDiscovery of low-frequency hippocampal theta rhythm in Ansells mole-rats C_LI

neuroscience↗

bioRxiv2019

PRMT5 in T helper lymphocytes is essential for cholesterol biosynthesis-mediated Th17 responses and autoimmunity

Protein Arginine Methyltransferase (PRMT) 5 catalyzes symmetric dimethylation of arginine, a post-translational modification involved in cancer and embryonic development. However, the role of PRMT5 in T helper (Th) cell polarization and Th cell-mediated disease has not yet been elucidated. Here we report that PRMT5 is necessary for Th17 differentiation and EAE, via enhancement of cholesterol biosynthesis and activation of ROR-{gamma}t. PRMT5 additionally controls thymic and peripheral homeostasis in the CD4 Th cell life cycle, as well as iNK T and CD8 T cell development or maintenance, respectively. Overall, our two conditional PRMT5 KO models that selectively delete PRMT5 in all T cells (T-PRMT5{Delta}/{Delta}) or Th cells (iCD4-PRMT5{Delta}/{Delta}) unveil a crucial role for PRMT5 in T cell proliferation, Th17 responses and disease. These results point to Th PRMT5 and its downstream cholesterol biosynthesis pathway as promising therapeutic targets in Th17-mediated diseases.

immunology↗