When the pretreatment and postinfusion variables were jointly analyzed, postinfusion immune-modulatory serum analytes such as GM-CSF, IL-15, IL-6, IL-2, TNF-α, and MCP-1 ranked higher compared with pretreatment product phenotype covariates for association with high-grade CRS and/or NE (Supplemental Table 4). Here, TNF is linked to congenital rubella syndrome.