Biology subjects

Hanayama, R.

Publications and source records attributed to Hanayama, R..

4 recordsLinked to original sources

bioRxiv2025

mRNA-Based Designer APCs Elicit Robust CD8⁺ and CD4⁺ T Cell Responses

mRNA-based therapeutics have demonstrated notable success in SARS-CoV-2 vaccines and are emerging in cancer immunotherapy. However, conventional mRNA cancer vaccines are limited by the low immunogenicity of tumor-associated and neoantigens. We addressed this limitation by formulating a modular, liposome-based mRNA cocktail comprising three distinct mRNAs encoding tumor antigen, the co-stimulatory molecule CD80, and membrane-tethered IL-2. Administration of this mRNA mixture transforms somatic cells into designer antigen-presenting cells (APCs) in vivo, which simultaneously express the antigen, a co-stimulatory molecule, and a cytokine. These designer APCs more effectively activated tumor antigen-specific CD8 T cells than mRNA encoding the antigen alone and elicited robust anti-tumor immune responses. In addition, substituting IL-2 in the mRNA mixtures with membrane-tethered IL-12 led to the expansion and differentiation of endogenous antigen-specific Th1 helper T cells in vivo. Importantly, this platform activated NY-ESO-1-specific CD8 T cells both in human PBMCs in vitro and in HLA-A*02:01-transgenic mice, highlighting its translational potential. This modular mRNA strategy reprograms somatic cells in situ into designer APCs, providing a flexible and translatable platform for precision immunotherapy.

immunology↗

bioRxiv2024

Probing nanomechanics by direct indentation using Nanoendoscopy-AFM reveals the nuclear elasticity transition in cancer cells

The assessment of nuclear structural changes is considered a potential biomarker of metastatic cancer. However, accurately measuring nuclear elasticity remains challenging. Traditionally, nuclear elasticity has been measured by indenting the cell membrane with a bead-attached atomic force microscopy (AFM) probe or aspirating isolated nuclei with a micropipette tip. However, indentation using a bead-attached probe is influenced by the cell membrane and cytoskeleton, while measurements of isolated nuclei do not reflect their intact state. In this study, we used Nanoendoscopy-AFM, a technique in which a nanoneedle probe is inserted into a living cell to directly measure nuclear elasticity and map its distribution. Our findings show that nuclear elasticity increases under serum depletion but decreases when serum-depleted cells are treated with TGF-{beta}, which induces epithelial-mesenchymal transition (EMT). Furthermore, we found that changes in nuclear elasticity correlate positively with trimethylation levels of histone H4 at lysine 20, rather than with nuclear lamins expression levels. These findings suggest that alterations in chromatin structure underlie changes in nuclear elasticity during cancer progression.

biophysics↗

bioRxiv2024

The Rubicon-WIPI axis regulates exosome biogenesis during aging

Cells release intraluminal vesicles (ILVs) in multivesicular bodies as exosomes to communicate with other cells. Although recent studies suggest an intimate link between exosome biogenesis and autophagy, the detailed mechanism is not fully understood. Here we employed comprehensive RNAi screening for autophagy-related factors and discovered that Rubicon, a negative regulator of autophagy, is essential for exosome release. Rubicon recruits WIPI2d to endosomes to promote exosome biogenesis. Interactome analysis of WIPI2d identified the ESCRT components that are required for ILV formation. Notably, we found that Rubicon is required for an age-dependent increase of exosome release in mice. In addition, small RNA sequencing of serum exosomes revealed that Rubicon determines the fate of exosomal microRNAs associated with cellular senescence and longevity pathways. Taken together, our current results suggest that the Rubicon-WIPI axis functions as a key regulator of exosome biogenesis and is responsible for the age-dependent changes in exosome quantity and quality.

cell biology↗

bioRxiv2023

Surface-engineered extracellular vesicles to modulate antigen-specific T cell expansion for cancer immunotherapy

Extracellular vesicles (EVs), including exosomes, are emerging as novel mediators of cell-cell communications, involved in various processes such as immune activation and immunosuppression. Despite the recent development of several EVs-based cancer immunotherapies, their clinical efficacy remained limited. Here, using fusion with tetraspanin as one of the EV engineering techniques, we created antigen-presenting extracellular vesicles (AP-EVs) to reproduce the functional characteristics of professional antigen-presenting cells (APCs). AP-EVs were also equipped with surface-bound IL-2, a feature not inherent to APCs, which facilitated selective delivery of IL-2 to antigen-specific CD8+ T cells. AP-EVs were engineered to express a peptide-major histocompatibility class I (pMHCI) complex, a costimulatory CD80 molecule, and IL-2, allowing the simultaneous presentation of multiple immune modulators to antigen-specific CD8+ T cells. This promoted the clonal expansion and differentiation of antigen-specific cytotoxic T lymphocytes, leading to potent anticancer immune responses. Combination therapy with AP-EVs and anti-PD-1 demonstrated enhanced anticancer immunity against established tumors compared with anti-PD-1 monotherapy. Our engineered EVs represent a novel effective strategy for cancer immunotherapy.

bioengineering↗