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Biology subjects

Honke, K.

Publications and source records attributed to Honke, K..

3 recordsLinked to original sources

Pseudovirus-Mediated Proximity Labeling Identifies Candidate Host Cell Membrane Proteins Involved in Viral Attachment

Viral infections represent a significant threat to humanity, as exemplified by the COVID-19 pandemic. To mitigate the associated damage, it is essential to understand the biological characteristics of causative viruses. In this study, we report a novel method for identifying host cell molecules (including virus receptor) required for viral attachment, referred to here as "Host Cell Attachment Factors (HCAFs)". Our approach utilizes proximity labeling (PL) technology: pseudoviruses engineered to express a PL enzyme are applied to host cells, where they bind and initiate proximity labeling. Since HCAFs are expected to be localized near viral attachment sites, candidate HCAFs are specifically tagged by the PL process. Analysis of influenza HCAFs enabled the identification of multiple candidate molecules. Subsequent virus attachment experiments using CHO cells suggested that NRP1 may serve as an HCAF for influenza viruses. Given its simplicity and rapid turnaround, this method is adaptable to a wide range of enveloped viruses, including pandemic viruses that require emergency analysis.

microbiology↗

Bimolecule detection for Extracellular Vesicle Screening

Extracellular vesicle (EV) has been investigated for use in clinical testing in recent years. Specific EV surface proteins provide distinguishing characteristics, but are insufficient for more detailed classification of EVs. Here, we suggest a novel "Bimolecular surface antigen expressed in EV" (BiEV) as a potential indicator for more efficient EV screening. A BiEV can be identified using a previously developed method, enzyme-mediated activation of radical sources, to label the components proximal (within 20 nm) to a given molecule. We examined the screening of cancer cell-secreted EV (cEV) included in serum EVs from a model mouse for lung cancer. The cEV-specific BiEVs were first identified by through a comparison of serum EVs from wild-type and lung cancer mice, showing that the CHL1-SLC4A1 bimolecule was a significant candidate for cEV-specific BiEV. Enzyme-linked immunosorbent assay quantification of CHL1-SLC4A1 BiEV appeared to suggest a potential for cancer screening of these mice. Using the same protocols, we found that CHL1-caspase 14 BiEV was significantly elevated in lung cancer patients compared with healthy persons. A BiEV strategy may be able to make a contribution to more effective EV screening, resulting in novel biological and clinical applications.

biochemistry↗

Proximity proteomics identifies cancer cell membrane cis-molecular complex as a potential cancer target

Cancer-specific antigens expressed in the cell membrane have been used as targets for several molecular targeted strategies in recent years with remarkable success. To develop more effective cancer treatments, novel targets and strategies for targeted therapies are needed. Here, we examined the cancer cell membrane-resident \"cis-bimolecular complex\" as a possible cancer target (cis-bimolecular cancer target: BiCAT) using proximity proteomics, a technique that has attracted attention in recent years. BiCATs were detected using a previously developed method, termed the enzyme-mediated activation of radical source (EMARS), to label the components proximal to a given cell membrane molecule. EMARS analysis identified some BiCATs, such as close homolog of L1 (CHL1), fibroblast growth factor 3 (FGFR3) and 2 integrin, which are commonly expressed in mouse primary lung cancer cells and human lung squamous cell carcinoma cells. Analysis of cancer specimens from 55 lung cancer patients revealed that approximately half of patients were positive for these BiCATs. In vitro simulation of effective drug combinations used for multiple drug treatment strategy was performed using reagents targeted to BiCAT molecules. The combination treatment based on BiCAT information moderately suppressed cancer cell proliferation compared with single administration, suggesting that the information about BiCATs in cancer cells is profitable for the appropriate selection of the combination among molecular targeted reagents. Thus, BiCAT has the possibility to make a contribution to several molecular targeted strategies in future.

biochemistry↗