Why does Covid have almost no effects for some patients and for others it can become lethal? A study based on two independent experiments, carried out by a Humanitas task force led by Professor Alberto Mantovani, and by the group of doctors and researchers of the Papa Giovanni XXIII health facility, coordinated by professor Alexander Rambaldi. They identified a molecule that indicates the severity of the disease, the molecule Ptx3. With this discovery, a turning point could be made in the care of patients suffering from Covid-19, it will be enough to do a simple blood test to find out the concentration of this molecule. High concentrations indicate that the patient is more at risk of suffering major consequences from the infection and therefore obliged to be hospitalized.

The study, called "Macrophage expression and prognostic significance of the long pentraxin PtxS in Covid-19“, Published in Nature Immunology, involved 96 patients in Humanitas and 54 in Pope John XXIII. Researchers investigated the mechanisms of innate immunity in the blood and lungs.

Alberto Mantovani, scientific director of Humanitas explained the discovery as follows: "The analysis revealed the role of a gene discovered by my group years ago, Ptx3: a molecule involved in immunity and inflammation, this molecule is present at high levels in the blood, lungs, cells of the former. line of defense and in the cells that line the inner surface of blood vessels. Important information since Covid patients have a very strong inflammation, which leads to thrombosis of the pulmonary microcirculation at the level of the endothelial cells ".

The two independent case studies, those of Milan and Bergamo, confirm that the measurement of Ptx3 is, to date, the most important prognosis factor associated with the worsening of patients' conditions.

"These data - explains Alessandro Rambaldi, director of the Hematology Unit and the Department of Oncology and Hematology of the Pope John XXIII hospital - confirm the centrality of endothelial damage in the most serious manifestations observed in Covid patients. The circulating levels of Ptx3, measured in the blood, will serve to guide the evaluation of the patient's response to treatments".

Covid-19 and Ptx3 molecule: With a blood test it is possible to establish the severity of the infection

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