Study identifies PTX-3 as a potential marker of long COVID and tissue damage

Study identifies PTX-3 as a potential marker of long COVID and tissue damage

A research team from MedUni Vienna was able to demonstrate that a specific component of the immune system (PTX-3) is still significantly elevated in the blood of patients with severe COVID-19 disease months after the acute infection has subsided. This study identified PTX-3 as a potential biomarker for existing tissue damage, long-term immune activation and also complications after COVID-19. The results were published in the top journal “Frontiers in Immunology” and make an important contribution to a better understanding of the consequences of COVID-19. Importantly, they may indicate another possible cause of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS).

As part of this study, the research groups led by Winfried Pickl and Rudolf Valenta (both from the Center for Pathophysiology, Infectiology and Immunology at MedUni Vienna) examined the levels of so-called acute phase proteins in the blood of 141 COVID-19 convalescents ten weeks and ten months after the acute infection. These were then compared with the values ​​of 98 uninfected control subjects. Acute phase proteins are components of the innate immune system that are rapidly released into the bloodstream during infections to fight off infection and control associated inflammatory and repair processes. During the acute phase of COVID-19, elevated serum levels of several such proteins from this group are associated with severe to fatal clinical consequences. As a rule, these markers return to their initial values ​​within a few days after the acute infection has subsided. However, the current study has shown for the first time that this is not the case for pentraxin 3 (PTX-3).

The research team's investigations found that PTX-3 levels were significantly higher in convalescent COVID-19 patients who had severe disease ten weeks after infection. Furthermore, ten months after the acute phase, some of these patients still had significantly higher PTX-3 levels compared to patients with mild disease or uninfected controls. “We assume that the higher PTX-3 values ​​either indicate ongoing tissue repair mechanisms or could indicate the presence of persistent SARS-CoV-2 remnants in the body,” says Winfried Pickl. “PTX-3 could therefore serve as a biomarker for long-lasting tissue damage and/or long-term immune activation resulting in possible complications after COVID-19,” adds Rudolf Valenta.

Previous studies have already described PTX-3 as a marker for severe COVID-19 in the acute stage. The current results suggest that the protein may also play a role in long-term recovery.

Scientists have already linked long-term immune activation due to ongoing repair processes and remaining virus components in the body to the development of long COVID-19. Our study provides important additional insights into these mechanisms.”

Bernhard scratch, first author of the study

Further research is needed to better understand the pathophysiology of COVID-19 and its long-term consequences and to confirm these new findings in prospective studies.

Sources: