Platelet Biochemistry Laboratory
Referents: Prof. Mauro Torti, Prof. Gianni Guidetti, Prof. Ilaria Canobbio
Co-workers: Mauro Vismara (post-doc), Luca Galgano (PhD student), Silvia Trivigno (PhD student)
In our laboratory, the biochemical events involved in the activation of platelets are studied in order to clarify their control mechanisms. Platelets play a crucial role in haemostasis, thrombosis and in numerous pathophysiological phenomena, including inflammatory processes, neurodegenerative diseases and tumor metastasis. The study of the involvement of platelets in these events represents a promising area of research capable of opening new scenarios in the biomedical field.
1) Study of signal transduction mechanisms in platelets in the context of haemostasis and thrombosis.
In-depth knowledge of the signal transduction mechanisms that mediate platelet activation is essential for identifying new drug targets for thrombotic pathologies, which represent the main cause of mortality and disability in industrialized countries. In this context, our research group deals with investigating the following fundamental aspects:
- the CD93 receptor in platelet function and thrombosis;
- role of the tyrosine kinase Pyk2 in thrombosis and thromboinflammation;
- contribution of the different isoforms of the enzyme phosphatidylinositol 3-kinase (PI3K) in platelet activation;
- signal transduction processes triggered by integrin-mediated platelet adhesion, G protein-coupled receptors and receptors containing ITAM domains;
- mechanisms of platelet activation induced by nanoparticles of environmental origin or developed for industrial and biomedical applications.
2) Analysis of metabolism and function of amyloid precursor protein (APP) and amyloid peptide A in platelets: a connection between hemostasis, thrombosis and Alzheimer's disease.
Alzheimer's disease is related to the accumulation of amyloid peptides in brain and cerebral vessels. In our laboratory we deal with:
- studying the effect of the accumulation of amyloid peptides in the peripheral circulation. We have shown that amyloid peptides are able to activate platelets and promote a state of chronic inflammation. We are now investigating the role of amyloid peptides in ROS formation in platelets;
- in collaboration with prof. Pula, from the University of Exeter (UK), we are working on defining the effect of peptides on the activation of immune system cells, in particular neutrophils, and on endothelial cells;
- studying the role of the amyloid precursor protein APP in pathophysiology of platelets, haemostasis and thrombosis.
3) Study of the role of platelets and microparticles released by platelets in metastasis.
Metastasis is strongly influenced by the interactions that can take place between cancer cells and the host organism. In this context it has been shown that platelets are essential components of the metastatic process and that their depletion, in thrombocytopenic patients or in animal models, limits the spread of the tumor. This suggests that pharmacological control of platelet activation may also represent a therapeutic weapon to block or contain metastatic spread. The goal of our study is to understand the molecular aspects underlying the contribution of platelets in metastasis. Specifically, our attention is focused on the role of platelet-derived microparticles (PMPs). PMPs are vesicles released by platelets following activation and represent important carriers of biological signals capable of modulating the activity of target cells.
With this line of research we aim at:
- analyzing the ability of PMPs to alter the metastatic potential of cancer cells;
- studying the molecular mechanisms underlying the prometastatic activity of PMPs;
- carrying out a comparative analysis of the effect of different pharmacological treatments on the prometastatic activity of platelets and PMPs.
Main collaborations of the research group:
- Mitsuhiko Okigaki (Department of Cardiovascular Medicine,Kyoto Prefectural University of Medicine, Kyoto, Japan);
- Emilio Hirsch (MBC, Università di Torino);
- Maria Enrica Tira (Dipartimento di Biologia e Biotecnologie, Università degli Studi di Pavia);
- Giampaolo Minetti (Dipartimento di Biologia e Biotecnologie, Università degli Studi di Pavia);
- Carlo Balduini, Patrizia Noris, Alessandro Pecci (Clinica Medica, IRCCS Policlinico San Matteo, Pavia);
- Barbara Oliviero, Stefania Mantovani (Malattie Infettive, IRCCS Policlinico San Matteo, Pavia);
- Giordano Pula (Institute of Biomedical & Clinical Science, University of Exeter Medical School, Exeter, UK);
- Satya P. Kunapuli (Departments of Physiology and Pharmacology and Sol Sherry Thrombosis Research Center, Temple University, School of Medicine, Philadelphia, Pennsylvania);
- Federico Galvagni, Maurizio Orlandini (Dipartimento di BiotecnologiSilvia Barbieri, Marta Zarà (Istituto cardiologico Monzino, Milano)e, Chimica e Farmacia, Università di Siena);
Main techniques and methods used by the research group: purification and analysis of blood cells (platelets and neutrophils); isolation and characterization of platelet microparticles and microvesicles; biochemical methods for protein analysis (electrophoresis, western blotting, immunoblotting, chemiluminescence analysis, spectrophotometry, spectrofluorimetry, cytofluorimetry); cell adhesion assays in static and flow conditions; optical microscopy (phase contrast and fluorescence); molecular biology techniques, DNA and RNA extraction, PCR; protein purification (expression in bacterial hosts, ion exchange chromatography, affinity chromatography, gel filtration, HPLC, FPLC); cell culture manipulation, maintenance, transfection, migration analysis, proliferation, metalloprotease release; use of genetically modified animal models (Mus musculus) (Pyk2KO, APPKO, APP23, CD93 KO).