Table 1.

Summary of antigenic tests results.

Donor	Supernatant Tested	Spike S1/S2 IgG Test		Nucleocapsid Test
		n. pos./n. Tested	% pos (Titer)	n. pos./n. Tested	n. pos. (Titer)
Donor A	Clones	0/91	0%	0/18	0%
	Pool	0/1	0%	0/1	0%
Donor B	Clones	2/29	6.9% 72.7 + 71.5 UA/mL *)	0/29	0%
	Pool	1/1	100% (14.9 UA/mL *)	1/1	100% (29.9 COI **)

* AU/mL: arbitrary units/mL (<12 AU/mL = non-reactive; 12–15 AU/mL = unclear; ≥15 AU/mL = reactive). ** COI: cutoff index (<1 = non-reactive; ≥1 = reactive).