2026年 3月 Student Monthly Progress を開催しました

3月27日 (金)にStudent Monthly Progressが開催されました。3名の大学院生が研究内容について発表しました。

 

【Presenters】

  1.  Mawiini MWANDABANTU : Laboratory of Theriogenology

  <A Toll-like receptor 4-mediated regulation of EGF production in the bovine uterine cell by palmitic acid>

 

  2. Yume MIMURA : Division of Risk Analysis and Management

  <A cDNA-clone-based reverse genetics system for Yezo virus reveals a dispensable N-terminal region of the glycoprotein precursor>

 

3.  Richard OBENG-KYEREMEH : Division of Biologics Development

  <The Role of LOX-1 in the Adaptive Immune Response Against SARS-CoV-2 in a Murine Model>

 

【Chairs】

Joseph NDEBE : Division of International Research Promotion

Mizuki MARUYAMA : Laboratory of Toxicology

 

 

 

   

❖座長レポート❖

 

《A Toll-like receptor 4-mediated regulation of EGF production in the bovine uterine cell by palmitic acid》

Mawiini MWANDABANTU

 

 

 

Mawini presented on the endometrial epidermal growth factor (EGF) as a key marker of fertility in dairy cattle, and its abnormal patterns are associated with reduced fertility. This study investigated whether palmitic acid (PA), a saturated fatty acid linked to inflammatory diseases via Toll-like receptor 4 (TLR4), affects EGF production. Endometrial epithelial and stromal cells were treated with PA or lipopolysaccharide (LPS), with or without a TLR4 inhibitor (VIPER). Both PA and LPS significantly increased EGF production. However, co-treatment with the TLR4 inhibitor reduced EGF production by about 70%, indicating that the effect is largely mediated through TLR4 signaling. Interestingly, VIPER increased TLR4 gene expression, while PA and LPS had no effect on its expression. These findings suggest that metabolic and inflammatory stimuli can enhance EGF production via TLR4, providing a potential mechanism linking hyperlipidemia to impaired fertility in dairy cattle. PA also affect reproctive hormnes such as eastrogen and progestrone, its assocaition with TLR4 remains unclear and future studies may explore the assocaition.

 

《A cDNA-clone-based reverse genetics system for Yezo virus reveals a dispensable N-terminal region of the glycoprotein precursor》

Yume MIMURA

 

 

Yume presentd on the Yezo virus (YEZV) an emerging tick-borne virus whose molecular characteristics remain unclear. To investigate viral gene functions, this study aimed to establish a reverse genetics system and examine the role of the N-terminal NSm region (27–68 aa) of the glycoprotein precursor (GPC), which may not be incorporated into viral particles. cDNA and helper plasmids were transfected into Vero E6 cells to generate recombinant viruses. A mutant lacking the NSm region (ΔNSm virus) was also constructed. The rescued wild-type virus showed properties similar to the parental strain, confirming successful system establishment. The ΔNSm virus was viable and showed earlier replication peaks in mammalian cells, whereas in tick-derived cells, its replication reached a similar timing but with lower titers compared to the wild type. These results indicate that the NSm region is not essential for viral replication but influences replication dynamics in a host-dependent manner, suggesting differences in GPC maturation between mammalian and tick cells. But as to whether this difference may affect the morphological characteristics or not, further study is need such as electron microscopy to ascertain thsese changes. The reason as to why the recombinant virus showed low titer in tick cells from which the virus was isolated needs to be further assessed.

 

 

 《The Role of LOX-1 in the Adaptive Immune Response Against SARS-CoV-2 in a Murine Model》

 Richard OBENG-KYEREMEH 

 

 

Richard presentd on how the protective immunity after vaccination depends on the generation of high-affinity neutralizing antibodies in germinal centers. LOX-1, a receptor expressed on dendritic cells and B cells, has been linked to innate immunity, but its role in vaccine-induced adaptive immunity remains unclear. This study investigated the effect of LOX-1 on immune responses following COVID-19 vaccination. Wild-type (WT) and LOX-1 knockout (KO) mice were immunized with whole virus particle or mRNA vaccines, and antibody responses, protection against viral challenge, and immune cell dynamics were evaluated. LOX-1 KO mice showed significantly reduced neutralizing antibody titers and impaired protection, despite only modest reductions in total IgG. They also exhibited decreased follicular helper T cells and impaired germinal centre B cell formation. These results suggest that LOX-1 plays a critical role in vaccine-induced immunity by promoting germinal center–dependent affinity maturation, highlighting its potential as a target for improving vaccine efficacy.