Biology subjects

Catala, A.

Publications and source records attributed to Catala, A..

3 recordsLinked to original sources

bioRxiv2026

Hierarchical classification of hematologic malignancies using epigenetic and genetic information

Molecular testing in hematology requires different assays for disease subgroup identification, risk stratification and selection of appropriate treatment regimens. Yet, molecular tests are not necessarily standardized between diagnostic laboratories, resulting in varying turnaround times and potentially divergent results. To resolve this issue and enable single-assay molecular testing, we have developed a hierarchical classification framework that combines epigenetic and genetic data from whole genome nanopore sequencing (WGNS) with machine learning to determine disease entities, epigenetic subgroups (epitypes) and genetic aberrations in hematopoietic neoplasms. We curated DNA methylation data from 5,420 samples and trained a classifier allowing entity-level diagnostics featuring 21 conditions, including healthy controls, acute and chronic myeloid and lymphoid neoplasms. This classifier was subsequently combined with entity-specific epitype classifiers predicting 44 therapeutically or prognostically relevant states, followed by integration of genetic data. Benchmarking of the combined (epi-)genetic testing strategy using WGNS confirmed high accuracy in the detection of diagnostic groups and risk stratification, and identified diagnosis-defining molecular alterations that were not reported by standard-of-care work-up.

cancer biology↗

bioRxiv2025

WNK kinase regulates plasma membrane levels of the WNT inhibitor RNF43

The E3 ubiquitin ligases RNF43 and ZNRF3 are key negative regulators of canonical WNT signaling, promoting turnover of the WNT receptors FRIZZLED and LRP5/6 at the plasma membrane. While their mechanism of action is well established, how RNF43/ZNRF3 themselves are regulated remains unclear. Here, we identify WNK kinases as novel upstream regulators of RNF43 through proximity labeling proteomics. Using gain- and loss-of-function approaches, we show that WNKs control RNF43 surface localization and thereby its ability to ubiquitinate and downregulate WNT receptors. Pharmacological inhibition of WNKs increases RNF43 membrane abundance and enhances WNT suppression - an effect abolished in RNF43/ZNRF3 double knockout cells and organoids. Mechanistically, WNK inhibition alters RNF43 trafficking and ubiquitination, revealing a role for WNKs in regulating its plasma membrane distribution. These findings define a new regulatory axis linking the pro-WNT activity of WNKs to RNF43/ZNRF3-mediated feedback inhibition. Targeting WNK now offers a novel therapeutic strategy to restore WNT pathway control in cancers with RSPO fusions or RNF43 mutations.

biochemistry↗

bioRxiv2021

Phage-like particle vaccines are highly immunogenic and protect against pathogenic coronavirus infection and disease

The response by vaccine developers to the COVID-19 pandemic has been extraordinary with effective vaccines authorized for emergency use in the U.S. within one year of the appearance of the first COVID-19 cases. However, the emergence of SARS-CoV-2 variants and obstacles with the global rollout of new vaccines highlight the need for platforms that are amenable to rapid tuning and stable formulation to facilitate the logistics of vaccine delivery worldwide. We developed a "designer nanoparticle" platform using phage-like particles (PLPs) derived from bacteriophage lambda for multivalent display of antigens in rigorously defined ratios. Here, we engineered PLPs that display the receptor binding domain (RBD) protein from SARS-CoV-2 and MERS-CoV, alone (RBDSARS-PLPs, RBDMERS-PLPs) and in combination (hCoV-RBD PLPs). Functionalized particles possess physiochemical properties compatible with pharmaceutical standards and retain antigenicity. Following primary immunization, BALB/c mice immunized with RBDSARS- or RBDMERS-PLPs display serum RBD-specific IgG endpoint and live virus neutralization titers that, in the case of SARS-CoV-2, were comparable to those detected in convalescent plasma from infected patients. Further, these antibody levels remain elevated up to 6 months post-prime. In dose response studies, immunization with as little as one microgram of RBDSARS-PLPs elicited robust neutralizing antibody responses. Finally, animals immunized with RBDSARS-PLPs, RBDMERS-PLPs, and hCoV-RBD PLPs were protected against SARS-CoV-2 and/or MERS-CoV lung infection and disease. Collectively, these data suggest that the designer PLP system provides a platform for facile and rapid generation of single and multi-target vaccines.

immunology↗