Researchers say the change in blood gene expression is associated with long COVID.
Researchers from the Mount Sinai Health System have published one of the first studies associating changes in blood gene expression during COVID-19 with long-term COVID as there are patients who carry this blood change more than a year after their hospitalization with severe COVID-19 .
Gene expression is the process by which the information contained in a gene (information consisting of DNA) is converted into a functional macromolecule (typically the synthesis of a protein). Gene expression is finely regulated by the cell. The results, published in Nature Medicine, highlight the need to pay more attention to the infection phase to better understand which and how the processes that lead to long Covid are (Long COVID is a clinical syndrome characterized by the presence of some symptoms related to SARS-CoV-2 infection (name of the virus that generates covid), which arise or persist even for weeks or months after recovery from Covid), this could help improve both prevention strategies and options for treatment for COVID-19 survivors who have persistent symptoms after infection.
Among other findings, the research team identified a number of genes that produce much less abundant antibodies in patients who later developed lung problems . In contrast, in patients with other symptoms, such as loss of smell or taste and sleep disturbances, the same antibody-producing genes were more abundant . These opposing patterns observed in the same cells, as well as other unique patterns observed in other cell types, indicate the existence of multiple independent processes leading to different long covid symptoms; these processes are already present during acute infection.
“Our results demonstrate that the molecular processes leading to long COVID are already detectable during COVID-19 infection,” said co-author Noam D. Beckmann, professor of medicine at Mount Sinai School of Medicine. “Furthermore, we see the initiation of multiple molecularly distinct pathways leading to all long COVID, providing a unique perspective on the differences between long-term symptoms.”
Using the Mount Sinai COVID-19 Biobank , researchers looked at gene expression data in blood samples from more than 500 patients hospitalized with COVID-19 between April and June 2020. More than 160 of these patients provided self-reported assessments of their symptoms still present six monthsor more after hospitalization. The team analyzed each gene expressed in blood for the association with each long-term COVID symptom, taking into account ICU admission, COVID-19 severity during hospitalization, gender, age, and other variables. The team then checked for specific associations for each of 13 different types of immune cells, including plasma cells. Finally, these associations were ranked by correspondence with changes in virus-specific antibody levels in patients.
“For long-lasting COVID symptoms, such as smell or taste disturbances, the link between gene expression of antibodies in plasma cells and actual levels of antibodies against the SARS-CoV-2 spike protein demonstrates a direct link with the body’s response to the virus,” said lead author Ryan C. Thompson. ” In contrast , the gene expression pattern for lung disease does not match SARS-CoV-2 specific antibody levels, highlighting the different immune processes that lead to long COVID and are triggered by COVID-19.”
“Our findings demonstrate that there is potential to use infection stage data to predict what might happen to the patient months later,” said co-author Alexander W. Charney, professor of genetics and genomic sciences. “We shouldn’t ignore the infection stage in long COVID research – this is clearly a critical window of time in which the body’s response to SARS-CoV-2 could set the stage for what’s to come.”
- Molecular states during acute COVID-19 reveal distinct etiologies of long-term sequelae (nature.com)
