Cell-mediated immune dysregulation in people recovering from COVID-19

Since the first case was reported in December 2019, the SARS-CoV-2 virus that causes COVID-19 has plunged into a pandemic, with cases and deaths still increasing. Ongoing observational clinical studies have become a priority for better understanding of how this previously unknown virus works, and the findings from this study provide better information on treatment and vaccine design. Can be given.

“Observative clinical studies of patients with COVID-19 helped clinicians better understand how the previously unknown SARS-CoV-2 virus works, and the findings from this study are It can provide better information on treatment and vaccine design. “

Researchers at the University of Alabama at Birmingham are lead author Jacob “Jake” Files and co-authors Nathan Erdmann, MD, Ph.D. And Paul Goepfert, MD, reported an observational study, “Persistent Cell-mediated Immune Dysregulation.” In individuals recovering from SARS-CoV-2 infection, “was published in the Journal of Clinical Investigation.

In a commentary on the UAB study published in the same issue, Dr. Philip Mad and Dr. Kenneth Remy of the University of Washington wrote: “The importance of these studies cannot be overemphasized, including how the immune responses generated by participants in the COVID-19 vaccine trial change over time. Information is key to potential changes to existing COVID-19 vaccines and treatments. ”

UAB researchers obtained blood samples and clinical data from 46 inpatient COVID-19 patients and 39 non-inpatients who recovered from confirmed COVID-19 infection. Both groups were compared to healthy COVID-19 negative controls.

Importantly, most individuals in the hospitalized group had the active SAR-CoV-2 virus in their blood and were hospitalized at the time of sample collection. All individuals in the non-hospitalized group were in convalescence at the time of sample collection.

From blood samples, researchers were able to isolate specific immune cell subsets and analyze cell surface markers. This complex information allows immunologists to analyze how each individual’s immune system responds during infection and during recovery.

Some of these results can reveal whether immune cells have been activated and depleted by infection.

In addition, researchers were able to analyze changes over time in two ways. The first was to observe changes in surface markers over time, defined as the number of days since the onset of symptoms in the unhospitalized sample. The second was to directly compare the frequency of these markers between the first and second visits of unhospitalized patients who collected blood samples at two consecutive time points.

The most surprising findings were about patients who were not hospitalized. UAB researchers saw up-regulated activation markers in hospitalized patients, but some activation and fatigue markers were more frequently expressed in non-hospitalized convalescent samples. I also found out that I was doing it.

Over time, these markers revealed that immunomodulatory dysfunction in unhospitalized individuals did not resolve immediately. In addition, dysregulation of T cell activation and malaise markers in the unhospitalized cohort was more pronounced in the elderly. “As far as we know, this is the first explanation for persistent immunomodulatory dysfunction due to COVID-19 in a large group of unhospitalized convalescent patients,” the researchers reported.

Detailed characterization of CD4 + T cell, CD8 + T cell activation and depletion phenotypes for a comprehensive study of in-hospital and non-hospital COVID-19 infected and post-infection immune cell subsets See studies that include. And B cells.

B cells and T cells from both patient cohorts had a phenotype consistent with activation and cell depletion throughout the first two months of infection. And in non-hospitalized individuals, activation markers and cell depletion increased over time. “These findings show the persistent nature of the adaptive immune system changes noted in COVID-19, suggesting long-term effects that may shape the maintenance of immunity to SARS-CoV-.” Said Mad and Remy in a comment. 2. ”

According to UAB researchers, the question currently under investigation is whether these observed immunological changes are associated with symptoms that have been experienced far beyond the acute infection, often referred to as “long COVID.”

Files, Erdmann, and Goepfert of the Journal of Clinical Investigation Report are co-authors of Sushma Boppana, Mildred D. Perez, Sanghita Sarkar, Kelsey E. Lowman, Kai Qin, Sarah Sterrett, Eric Carlin, Anju Bansal, Steffanie Sabbaj, Olaf Kutsch UAB School of Medicine. James Kobie from the Infectious Diseases Division. Dustin M. Long, Faculty of Public Health, Faculty of Biostatistics, UAB.

Source: Eurekalert

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