Table 5.

Comparison of ELISA and ELISpot techniques for IFN-γ quantification.

	ELISpot	ELISA
Possible quantification of IFN-γ producing CAR-T cells	Yes	No
Quantifiable data provided	Number of spots for 10 000 or 100 000 cells	Concentration in pg/mL
Number of CAR-T cells required per condition	Approximately 10 000 to 100 000	Approximately 10 000 to 100 000
Possible stimulation methods	Recombinant protein/beads/cell lines	Recombinant protein/beads/cell lines
Effector:Target ratio commonly used	At least 3 ratios (0.1/1, 1/1, and 1/10)	At least 3 ratios (0.1/1, 1/1, and 1/10)
Incubation time	Most often 4 to 24 h	Most often 16 to 24 h
Cost	- Around €200 to €400 for a pre-coated 96-well plate - Approximately €50/test when using strips, but well coating needs to be validated internally with common references across labs	- Around €200 to €800 for a pre-coated 96-well plate - Approximately €60/test when using strips, but well coating needs to be validated internally with common references across labs