Biology subjects

Leclerc, E.

Publications and source records attributed to Leclerc, E..

2 recordsLinked to original sources

bioRxiv2026

Using digital holographic microscopy (DHM) to monitor effects of extracellular matrix (ECM) glycation on cancer cell morphology and migration

The extracellular matrix (ECM) is a complex network of ubiquitously present acellular material that plays a critical role in cell proliferation, migration, invasion, and tissue morphogenesis. Non-enzymatic glycation of ECM modifies the structure and function of ECM proteins and can support a pro-inflammatory milieu in the tumor microenvironment. However, the impact of glycated ECM on cancer cell growth remains underexplored despite its importance in facilitating disease progression. Here, we investigate the effect of ECM glycation on cancer cell morphology and migration behavior. We used methylglyoxal (MG) as a glycation agent and collagen as our ECM model protein. For in vitro growth analysis, breast cancer cells were seeded on growth surfaces coated with both non-glycated and glycated collagen. Cell behavior was monitored for 24 hours using a real-time holographic imaging system. Holographic image analysis revealed significant differences between non-glycated and glycated growth substrates in cell spreading area, eccentricity, perimeter length, optical thickness, and optical volume, as well as cell migration and motility, which directly influence cell adhesion and proliferation. These changes were found to be cell line biased. Overall, our findings suggest that ECM glycation has a significant effect on cell morphology, migration and cell growth. Holographic live cell imaging was determined to be an excellent method to monitor cells without the need for any labeling and with minimal perturbations.

cell biology↗

bioRxiv2025

A biotin ligation assay reveals a complex proxiome for HLA-A2 and implicates MIA3 in cell surface expression of MHC class I molecules

Antigen presentation via MHC class I molecules (MHC-Is) is a turning point in the establishment of immune responses to endogenous threats, such as viruses. From their synthesis to their cell surface display, MHC-Is travel to many compartments, including the ER, Golgi, and endosomes. They come close to a plethora of molecules, some of which regulate directly or indirectly their folding and trafficking. While many of these proteins are well characterized, such as those found in the peptide loading complex, others remain to be discovered. The proxiome can be studied using proximity labeling assays, such as BioID, which relies on a biotin ligase fused to a bait of interest that biotinylates lysine residues on nearby proteins. These modified targets can then be purified and identified by mass spectrometry. By fusing BioID to the HLA-A2 cytoplasmic tail, we have applied this technique to the MHC-I antigen and identified 209 potential specific interactors in HEK293 cells, including PDZD8 (LYVAC) and MIA3 (Tango1). We knocked out MIA3 in HEK293 cells and measured an increase in the expression of MHC-I molecules, suggesting a role for this vesicle budding protein in the regulation of MHC-I trafficking. Notably, MHC-I crosslinking identified targets that connect reverse signalling to diverse metabolic processes. Altogether, our results underscore the promise of HLA-coupled biotin ligases as a powerful approach to dissect antigen presentation pathways.

immunology↗