Table 4: Recommended cytokines to measure in cell therapy trials.

Cytokines are listed with associated roles in immune effector-related toxicities.

Cytokine	Toxicities	Roles
CSF-1		Regulates monocyte/macrophage differentiation [99]
GM-CSF	CRS, HLH and neurotoxicity	Drives CRS and neuroinflammation [63]
IFNα		MSC production [100] and cytokine delivery, induces expression of tumor suppressor proteins [101]
IFNγ *	CRS and HLH	Contributes to immunotherapy, tumor suppression and the efficacy of immune checkpoint blockade [102]
IL-1 *	CRS	Innate immunity [103]
IL-2 *	CRS, HLH and neurotoxicity	Promotes expansion of T and NK cells
IL-4		Promotes B cell proliferation; mediates inflammation [104]
IL-5		Promotes B cell proliferation [105]
IL-6 *	CRS and HLH	Associated with CRS onset and severity
IL-8	CRS	May be predictive of resistance to ICIs [106]
IL-10	CRS
IL-12		Activation and regulation of macrophages, T and NK cells [107]
IL-13		Promotes B cell proliferation; mediates inflammation [104]
IL-15 *	CRS	Induces proliferation of CD8 memory and NK cells, cytotoxicity, and release of other cytokines (e.g. IFNγ) [108]
IL-17		Pro-inflammatory cytokine [109]
IL-21		Activates STAT3 signaling in T cell and B cell differentiation [110]
TGFβ		Promotes cancer progression [111]
TNFα *	CRS and HLH	Mediates inflammation, anti-tumor responses and infection [112]

^*Indicates cytokine should be included in a basic minimum panel.