One adverse effect of this treatment is cytokine release syndrome (CRS) which is attributed to higher-than-normal release of inflammatory cytokines such as interleukin-6 (IL-6), interferon gamma (IFNγ), tumor necrosis factor-a (TNF-α) and interleukin-1 (IL-1) [27]. This evidence concerns the gene IL6 and congenital rubella syndrome.