CXCL10 and myocarditis: Systemic cytokine responses are closely associated with systemic reactogenicity,12,13 and cytokine genes preferentially upregulated in the PBMCs of NHPs receiving repRNA/LNP, such as CXCL10 and IL1RA, have also been reported to be upregulated in a cohort of patients who developed myocarditis/pericarditis following mRNA/LNP vaccination.29