Obesity, Insulin Resistance, and PASC: Persistent SARS-CoV-2 infection and Inflammation in Human Adipose Tissue

Introduction: Long COVID is a heterogeneous condition characterized by a wide range of symptoms that persist for 90 days or more following SARS-CoV-2 infection. Now more than five years out from the onset of the SARS-CoV-2 pandemic, the mechanisms driving Long COVID are just beginning to be elucidated. Adipose tissue has been proposed as a potential reservoir for viral persistence and tissue dysfunction contributing to symptomology seen in Long COVID.

Objective: Our goal was to establish whether SARS-CoV-2 RNA or inflammatory responses in adipose tissue were more likely to be present in individuals with Long COVID.

Methods: We analyzed subcutaneous adipose tissue (SAT) from participants with Long COVID compared to those with those classified as "indeterminate" based on the RECOVER-Adult Long COVID Research Index (12-47 months post-infection. We used quantitative real-time PCR to assess viral RNA and performed bulk RNA-sequencing to assess the overall inflammatory environment.

Results: We found no evidence of persistent SARS-CoV-2 RNA in adipose tissue in any participant. We found no significant changes in gene expression profiles between Long COVID samples and samples from indeterminant participants.

Conclusion/Discussion: Thus, viral persistence and inflammation (as measured by transcriptional profile) in subcutaneous adipose tissue do not appear to play a clear role in Long COVID pathophysiology, though further research is needed.

Key Topics:

• Assay and in vitro studies to gain mechanistic insights
• Biomarker, in-depth phenotyping assays and in vitro studies using tissue and other biospecimens
• Chronic immune dysfunction
• Long COVID and other chronic conditions
• Remaining gaps in tissue-specific manifestations of Long COVID