Frontiers in Immunology Publishes New Study Data from IncellDx Supporting a Model for Understanding Long COVID’s Cause

SAN CARLOS, Calif.–(BUSINESS WIRE)–IncellDx, a precision medicine company, today announced the journal Frontiers in Immunology has published a study detailing a framework for understanding the potential mechanism of, and potential treatment for, Post-Acute Sequelae of COVID-19 (PASC), also known as long COVID or long haul COVID.

“Recent analysis confirms long COVID impacts a significant number of people, and its prevalence may increase due to the emergence of the Omicron variant,” said Bruce Patterson, MD, CEO of IncellDx. “We know it’s a highly prevalent and growing problem. What physicians have been lacking is understanding of the underlying cause of long COVID, and a way to objectively diagnose and treat it. We believe this study provides additional evidence for a meaningful path forward for diagnosis and treatment.”

In the study, Persistence of SARS CoV-2 S1 Protein in CD16+ Monocytes in Post-Acute Sequelae of COVID-19 (PASC) Up to 15 Months Post-Infection, patients with previous COVID infection and lingering symptoms were found to have a distinct immunologic profile characterized by differentiated proportions of monocyte subsets. In the study, the presence of SARS-CoV-2 S1 protein was investigated in 46 people. T-cell, B-cell, and monocytic subsets were analyzed in both severe COVID-19 patients and in patients with post-acute sequelae of COVID-19 (PASC). The levels of both intermediate (CD14+, CD16+) and non-classical monocyte (CD14Lo, CD16+) were significantly increased compared with healthy controls. Neither monocyte subset was elevated in cases of severe COVID-19. Additionally, the SARS-CoV-2 protein subunit S1 was present in non-classical monocytes among patients thought to have PASC for up to 16 months following initial infection. Monocytes, a type of white blood cell, are involved in adaptive immunity and are instrumental in attacking viruses and other pathogens.

A previous paper from IncellDx in Frontiers in Immunology proposed the first model for diagnosing, indexing and monitoring long COVID. In that study, Immune-Based Prediction of COVID-19 Severity and Chronicity Decoded Using Machine Learning, 224 individuals, including healthy controls and patients spanning the COVID-19 disease continuum, were assessed using machine learning for severity and chronic symptoms following initial infection. CCL5/RANTES, IL-2, IL-4, CCL3, IL-6, IL-10, IFN-γ, and VEGF were all significantly elevated in long COVID patients compared to healthy controls (P<0.001), while GM-CSF and CCL4 were in significantly lower levels than healthy controls (P=0.01). Data were analyzed to generate objective disease scores for PASC and severe COVID patients.

“The S1 protein is believed to cause the inflammation, specifically the vascular inflammation, that contributes to symptoms characteristic of long COVID,” continued Patterson. “We at IncellDx would like to congratulate all the groups that contributed to this critical publication showing persistence of the S1 protein in white blood cells months and now almost 2 years post SARS-CoV-2 infection in patients suffering from long COVID or PASC. Critically, the data also show persistence of COVID RNA in these cells but whole genome sequencing revealed that they are fragments of RNA incapable of replication. We are also excited to be deploying Quantum Si’s single molecule protein sequencing platform so that we can identify Omicron long haulers and determine whether mutated S1 proteins contribute to a different disease course in adults and children in newer variants such as Delta and Omicron.”

Purvi Parikh, MD, allergy and immunology specialist at NYU Langone Medical Center and co-founder Chronic COVID Treatment Center, said, “We knew persistent inflammation was likely the cause of PASC and now with more evidence on the nature of inflammation, we can use targeted therapies to hopefully bring these patients relief from this relentless condition.”

About IncellDx

IncellDx is a precision medicine company advancing novel diagnostics and prognostics to better understand and treat infectious disease and cancer. The company’s innovative technology platform enables simultaneous cell classification and single cell analysis of proteomic and genomic biomarkers. The company launched the Chronic COVID Treatment Center to apply precision medicine approaches to evaluate, characterize and more effectively address chronic COVID.


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