Biology subjects

Wang, L.-C.

Publications and source records attributed to Wang, L.-C..

2 recordsLinked to original sources

bioRxiv2022

Aeromonas hydrophila induces skin disturbance through mucosal microbiota dysbiosis in Pangasianodon hypophthalmus

Bacterial pathogens are well-equipped to adhere to and initiate infection in teleost fish. The fish skin mucus serves as the first barrier against environmental pathogens. The mucus harbors commensal microbes that form the microbiota, impacting the host physiological and immunological regulation. However, how the skin mucosal microbiota responds to the presence of pathogens remains largely unexplored. Thus, little is known about the status of skin mucus prior to the infection with noticeable symptoms. In this study, we aim to investigate the interaction between pathogen and skin mucosal microbiota, as well as the fish skin immune responses in the presence of pathogens. By challenging striped catfish (Pangasianodon hypophthalmus) with different concentrations of bacterial pathogen Aeromonas hydrophila (AH), the skin immune response and the mucosal microbiota were examined by qPCR and 16S rRNA gene sequencing analysis. We found a pathogen concentration able to stimulate the skin immune response associated with the significant mucosal microbiota change and re-confirmed with the ex vivo fish skin model. Further analysis indicated that the change was attributed to the significant increase in opportunistic pathogens over AH. We concluded that the presence and increase of AH results in dysbiosis of mucosal microbiota that can stimulate skin immune response. We believe our work can shed some light on host-pathogen-commensal microbiota interaction and therefore contribute to aquaculture infection prevention. IMPORTANCEThe fish skin mucosal microbiota is essentially the first barrier in response to the presence of pathogens. This study is the first study to elucidate the interaction between the AH, the skin mucosal microbiota, and the striped catfish skin at the initiation stage of infection. Our study provides a platform to study both the correlation and causation of the interaction between pathogen, the fish skin, and the skin mucosal microbiota. This work provides information that changes in the AH-induced mucosal microbiota result in skin disturbance with immune stimulation.

microbiology↗

bioRxiv2021

Gonococcal invasion into epithelial cells depends on both cell polarity and ezrin

Neisseria gonorrhoeae (GC) establishes symptomatic infection in women from the cervix, lined with heterogeneous epithelial cells from non-polarized stratified at the ectocervix to polarized columnar at the endocervix. We have previously shown that GC differentially colonize and transmigrate across the ecto and endocervical epithelia. However, whether and how GC invade into heterogeneous cervical epithelial cells is unknown. This study examined GC entry of epithelial cells with various properties, using human cervical tissue explant and non-polarized/polarized epithelial cell line models. While adhering to non-polarized and polarized epithelial cells at similar levels, GC invaded into non-polarized more efficiently than polarized epithelial cells. The enhanced GC invasion in non-polarized epithelial cells was associated with increased ezrin phosphorylation, F-actin and ezrin recruitment to GC adherent sites, and the elongation of GC-associated microvilli. Inhibition of ezrin phosphorylation inhibited F-actin and ezrin recruitment and microvilli elongation, leading to a reduction in GC invasion. The reduced GC invasion in polarized epithelial cells was associated with non-muscle myosin II-mediated F-actin disassembly and microvilli ablation at GC adherence sites. Surprisingly, intraepithelial GC were only detected inside epithelial cells shed from the cervix, but neither in the ectocervix nor the endocervix, by immunofluorescence microscopy. We observed similar ezrin and F-actin recruitment in exfoliated cervical epithelial cells but not in those that remained in the ectocervical epithelium, as the luminal layer of ectocervical epithelial cells expressed ten-fold lower levels of ezrin than those beneath. However, GC inoculation induced F-actin reduction and myosin recruitment in the endocervix, similar to what was seen in polarized epithelial cells. Thus, polarized expression of ezrin at the apical surface of epithelial cells inhibits GC invasion, while non-polarized expression of ezrin promotes GC invasion by driving actin accumulation and microvilli elongation.

cell biology↗