Nature

Long COVID patients show distinct immunologic, hormonal patterns

September 28, 2023

Significant biological differences were found between study participants with long COVID (LC) and matched healthy (HC) and convalescent (CC) participants.

• This cross-sectional study, which enrolled 273 individuals with or without LC, used multidimensional immune phenotyping and machine learning models to identify biological features of LC.
• Relative to matched controls, the LC cohort demonstrated marked differences in circulating myeloid and lymphocyte populations, as well as evidence of exaggerated humoral responses against SARS-CoV-2. In addition, more pronounced antibody responses directed against non-SARS-CoV-2 viral pathogens—notably Epstein-Barr virus—were also observed among LC participants.
• Concentrations of soluble immune mediators and hormones varied among groups, including lower cortisol levels among the LC cohort. The decreased cortisol levels, however, weren't associated with compensatory increases in ACTH levels, suggesting inappropriate blunting of the hypothalamic-pituitary axis response.
• The findings may help guide future research into the pathobiology of LC and aid in developing relevant biomarkers.

Source:

Klein J, et al. (2023, September 25). Nature. Distinguishing features of Long COVID identified through immune profiling. https://pubmed.ncbi.nlm.nih.gov/37748514/