Table 1.

Quantifying the relative α2–3 and α2–6 binding affinities of SC18, NY18, and AV18 HAs

H1N1 HAs	6′SLN-LN		3′SLN-LN
	n	K′d	n	K′d
SC18	1.3	5.5 pM	n.b.	n.b.
NY18	1.2	6.3 nM	1.3	50 pM
AV18	0.9	1 μM	1.3	5 pM

Relative binding affinities of SC18, NY18, and AV18 HAs to representative long α 2–3 and α 2–6 glycans. n.b. indicates no binding. The parameters n and K′_d were determined as described in Materials and Methods and elaborated in SI Fig. 7. These parameters were obtained to purely quantify the relative binding affinities of the HAs, and hence their absolute values should be viewed only in this context.