Research

 

Nowadays, our principal research focuses on understanding the mechanisms of peptide/protein self-assembly and their roles in the delicate balance between health and disease in gluten-related disorders, such as celiac disease, non-celiac gluten/wheat sensitivity, and gluten ataxia. From our investigations, it is clear that gluten peptides are not only pathogenic for celiac patients. They possess interesting molecular and supramolecular features that could be used to elucidate the mechanism of cellular uptake and translated to other pathologies, such as aggregopathies and even cancer. This translational research is complemented by other, more basic projects in the areas of protein/peptide-protein interactions and functional molecules such as photoswitchable biosystems.

Gluten related-disorders and Protein-Protein Interaction

Gluten-related disorders are a group of diseases that involve immune activation triggered by gluten ingestion. These disorders have a high prevalence in Western societies, around 5% worldwide, because gluten is present in wheat, rye, barley, and some varieties of oats.

It is accepted that the incomplete proteolysis of the gluten proteins is responsible for disease in susceptible individuals. From a chemical perspective, research efforts to date have focused on identifying, quantifying, and separating gluten components and on linking them to their pathological roles in vitro and in vivo. Interestingly, while the primary structure of the molecules involved in the disease is known, there is a lack of information about their intrinsic behavior –such as their folding and molecular organization- under physiologically relevant conditions.

Gliadin and its 33-mer fragment have a central pathogenic role in the context of gluten-related. The aim of the present project is to elucidate the molecular, structural, and supramolecular basis of 33-mer oligomerization and the role of the 33-mer nanostructures in the delicate balance between health and disease.

Oligomerization and conformational transition towards the β-parallel structure are hallmarks of Alzheimer’s disease, Parkinson’s disease, and prion disease.

Based on these similarities, the relationship between 33-mer accumulations, due to proteolytic resistance, and subsequent oligomerization can be the previously unknown trigger of disease before the onset of inflammation. This hypothesis opens new avenues for understanding and treating this common pathology.

To test this hypothesis, we moved from chemical and biophysical studies to immunological research, reporting for the first time that only large 33-mer structures induce an innate immune response in macrophages, mediated by Toll-like receptor (TLR) 4 activation. This result opens the understanding of the early stages of the disease. It connects the activation of the innate immune system, triggered by the presence of 33-mer protofilaments, for the first time.

The current project combines chemical and biological methodologies and approaches, including peptide chemistry, structural and supramolecular characterization methods, cellular biology, proteomics, and super-resolution optical microscopy. By combining my research expertise with that of my collaborators, we can quantify and understand the role of 33-mer oligomers as disease modulators.

Our findings will open new avenues for understanding gluten-related disorders, with a focus on the design of new prevention and therapeutic targets beyond the gluten-free diet.

Methods

Our research focuses on understanding the self-assembly of peptides and small molecules under physiologically relevant conditions and their function in cellular models. We employ various tools from peptide science (molecules), biophysical chemistry (systems), and cell biology (function) at different levels of complexity, with a special emphasis on characterizing biomolecules and their self-assembly properties. To investigate their cellular behavior, we use different cellular models, such as differentiated Caco-2 cells in Transwell systems, which allow us to study their uptake, transport, and effects on the gut barrier, as Caco-2 cells serve as a model for the small intestine. Another model we use is the SH-SY5Y cell line, widely employed in neuroscience research to study neurodegenerative diseases, neurotoxicity, and neuronal differentiation. Additionally, we conduct real-time wound-healing assays. Recently, we have been working on connecting different cell types as a model for small organs under dynamic conditions to investigate the gut-brain axis.

The final aim is to gain a deep understanding of the relationships among molecular structure, morphology, and function in biologically relevant environments.