HT17. COVID-19 vaccinated individuals may be ill…See more

When the researchers blocked the activity of CXCL10 and IFN-gamma, this infiltration was substantially reduced, and cardiac troponin levels dropped, even as the overall immun

e response to the vaccine remained largely intact. This was a critical finding: it suggested that the inflammatory damage to the heart might be separable from the vaccine’s protective immune function.

The team went further, using a cutting-edge technology developed in Wu’s laboratory. Human skin or blood cells can be transformed into blank stem-like cells and then guided to differentiate into heart muscle cells, macrophages, and the cells that line blood vessels. These cells can then be assembled into tiny spherical structures that mimic the beating, contracting behavior of actual heart tissue — what the researchers call “cardiac spheroids.”

When these cardiac spheroids were treated with cytokine-enriched fluid from vaccine-stimulated immune cells, markers of cardiac stress increased significantly and the spheroids’ ability to contract rhythmically was impaired. When cytokine inhibitors were applied, much of this damage was reversed.