What do you see as the most important developments in your field in the past 15 years?

Aberrant protein aggregation has been considered, and is still increasingly recognized, as an extremely important process in biology, pathology and biotechnology. Uncontrolled protein aggregation is a relevant process in the most diffuse neurodegenerative diseases, such as Alzheimer’s, Parkinson’s, frontotemporal dementia and amyotrophic lateral sclerosis. It is also relevant in cancer, although it is probably so far underestimated there. Scientists have been highly engaged in studying the fundamentals of protein aggregation for half a century by now, in the test-tube using purified proteins, in cell cultures, in animal models and in the clinic. In spite of the many efforts expended in this direction, we have been to some extent frustrated, until recently, by the complexity of the problem, including the heterogeneity of the mechanisms of protein aggregation and of the resulting structures, and the different mechanisms through which these species cause cell dysfunction and death.

This has not resulted from the inability of the scientists themselves. I have indeed had the pleasure to meet incredible people in the past 25 years of activity in this field all over the planet. It rather resulted from the lack of technology of a high enough level to meet the challenges presented by the complexities in this field. However, in the past 15 years there has been a great deal of progress. The structures of amyloid fibrils, which are definitely the most widely diffused protein aggregates in pathology, are now being solved with solid-state nuclear magnetic resonance (ssNMR) and, in particular, by cryogenic electron microscopy (cryoEM) with the resolution typical of folded globular proteins. The advent of super-resolution microscopies has allowed the detection of very small protein aggregates that have remained invisible with conventional microscopic techniques, allowing the various species to be distinguished by size, molecular interactions with other proteins or organelles, and so on. Even in kinetics, the elaboration of complex master equations for complex fitting of multiple kinetic traces has allowed us to detect micro-steps of the protein aggregation process with amazing accuracy and to find out which of them are affected by specific chaperones, drugs, and other circumstances. Progress in immunology has led to the first disease-modifying drugs against Alzheimer’s disease approved by the US FDA and, more generally, four first-in-class drugs have been developed against protein misfolding diseases over the past 15 years, which have the avoidance of misfolding/aggregation of the proteins involved as molecular targets.

Overall, therefore, the most important developments in this field are associated with the important technological progress seen in these past 15 years, and new optimism is finally evident in our community.

What roles in the scientific community beyond your own research group have you most enjoyed?

I think that science needs to be collegial. Times have changed since great scientists with great intuition made great discoveries. Now we need to integrate our efforts for big projects and to respond to challenging unresolved questions. My feeling is that we do not work hard enough in that direction. A single lab may develop an important expertise, but this would result in a significant added value if we are able to put skills from different labs together. Of course, this is not effortless – it is indeed time-consuming, it requires a significant level of coordination, and different views have to be reconciled – but I see many outstanding papers that have resulted from placing together different skills and techniques to respond to an important biological question. To be frank, this is also what I enjoy most in the research community. In my small experience, I see that the most significant papers have been those that were not born and finished in my own lab, but those involving other people. It is a great opportunity to learn a different forma mentis (mindset), to learn new experimental approaches, and to see things from a different angle. I love these multicentric papers, both those where I was and was not involved, where different scientists provide distinct yet significant contributions. The strongest evidence is that obtained with different techniques and approaches, often involving different investigators, and I sense we have achieved a more complete piece of work when this is realized.

If you had more time for work, how would you spend it?

Definitely by reading papers and reviews. I always feel I do not do that enough. In my research field there are many investigators from different countries and many papers are being published. When I talk to my colleagues working in different areas, I see this is the rule rather than the exception. There is a great deal of information in papers published by others and I do not have the time to read even a small fraction of them. This is a great loss, I believe, because all this information is precious and we all would be more expert and skilful if we knew it. It would allow us to set up more relevant projects, design better individual experiments, interpret the data more comprehensively, and discuss findings more wisely. A dream of mine is that the artificial intelligence that is increasingly discussed nowadays will help us to do this job. Human beings cannot have the time to read all these papers, remember them, and use them appropriately, even from a single area of research.

Introduction to Fabrizio Chiti’s work

Research summary

The research of Fabrizio Chiti’s lab uses a multi angle approach, often as part of national and worldwide collaborations, to investigate the mechanisms by which soluble proteins assemble into ordered aggregates and by which the resulting aggregates cause cell dysfunction. In addition to classical molecular biology and biochemistry, the experimental work involves biophysical techniques for the characterization of the folding and aggregation processes such as turbidimetry, fluorescence, circular dichroism and Fourier-transform infra-red spectroscopies, static and dynamic light scattering, microfluidics, plate readers, stopped-flow devices, nuclear magnetic resonance, electron microscopy and atomic force microscopy, as well as infrastructures for protein engineering and the high-throughput purification of protein variants. Computational methods for the analysis and interpretation of kinetic data related to folding and aggregation are also used. Studies of the interaction of protein aggregates with cells are based on the utilization of cell cultures and specific kits for protein expression and protein internalization, as well as siRNA, inhibitors, and specific protocols to assess their viability, oxidative stress and calcium homeostasis. Confocal microscopy, Western blotting and super-resolution STED microscopy are widely used.

Lab webpage: https://www.sbsc.unifi.it/vp-209-gruppo-chiti.html

Four recent/key papers:

Errico, S. et al.(2020) Making biological membrane resistant to the toxicity of misfolded protein oligomers: a lesson from trodusquemine. Nanoscale 12, 22596–22614. https://doi.org/10.1039/D0NR05285J

Fusco, G. et al. (2017) Structural basis of membrane disruption and cellular toxicity by α-synuclein oligomers. Science 358, 1440–1443. https://doi.org/10.1126/science.aan6160

Cascella, R., Bigi, A. et al. (2022) A quantitative biology approach correlates neuronal toxicity with the largest inclusions of TDP-43. Sci. Adv. 8:eabm6376. https://doi.org/10.1126/sciadv.abm6376

Bigi. A., Fani, G. et al. Putative novel CSF biomarkers of Alzheimer’s disease based on the novel concept of generic protein misfolding and proteotoxicity: the PRAMA cohort. Transl. Neurodegener. (in press)

More information on the FEBS 60th Anniversary Lecture at the FEBS Congress

Fabrizio Chiti will deliver the FEBS 60th Anniversary Lecture at the 48th FEBS Congress in Milano, Italy, on Wednesday 3rd July 2024 on ‘Protein misfolding and aggregation: role in aging, neurodegeneration, non-neuropathic diseases and cancer’: 2024.febscongress.org/

Top image of post: by Gerd Altmann from Pixabay