Table 1.

Sequences of the 2009 H1N1 HA protein that contain CD4⁺ T-cell epitopes

Amino acid region	Peptide sequencesa,b,c	HLA restriction	Response frequency
1–20	MKAILVVLLYTFATANADTL	DR0404	1 of 4
33–52	VDTVLEKNVTVTHSVNLLED	DR0701	7 of 7
57–76	KLCKLRGVAPLHLGKCNIAG	DR0701	1 of 7
113–132	IDYEELREQLSSVSSFERFE	DRB5	4 of 4
121–140	QLSSVSSFERFEIFPKTSSW	DR1101	2 of 3
		DRB5	4 of 4
129–148	ERFEIFPKTSSWPNHDSNKG	DR1101	2 of 3
161–180	FYKNLIWLVKKGNSYPKLSK	DR1101	3 of 3
		DRB5	3 of 4
209–228	YQNADAYVFVGSSRYSKKFK	DR1101	2 of 3
217–236	FVGSSRYSKKFKPEIAIRPK	DRB5	1 of 4
225–244	KKFKPEIAIRPKVRDQEGRM	DRB5	1 of 4
241–260	EGRMNYYWTLVEPGDKITFE	DRB5	1 of 4
249–268	TLVEPGDKITFEATGNLVVP	DR0401	2 of 7
		DR0701	6 of 7
257–276	ITFEATGNLVVPRYAFAMER	DR0401	1 of 7
		DR0701	7 of 7
265–284	LVVPRYAFAMERNAGSGIII	DR0401	7 of 7
		DR0404	4 of 4
305–324	TSLPFQNIHPITIGKCPKYV	DR0701	6 of 7
313–332	HPITIGKCPKYVKSTKLRLA	DR1101	2 of 3
321–340	PKYVKSTKLRLATGLRNIPS	DR1101	2 of 3
329–348	LRLATGLRNIPSIQSRGLFG	DR0401	4 of 7
		DR0404	2 of 4
393–412	TNKVNSVIEKMNTQFTAVGK	DR0101	2 of 4
		DR0401	4 of 7
		DR0404	2 of 4
401–420	EKMNTQFTAVGKEFNHLEKR	DR0401	1 of 7
		DR1101	2 of 3
409–428	AVGKEFNHLEKRIENLNKKV	DR1101	2 of 3
433–452	LDIWTYNAELLVLLENERTL	DR0101	2 of 4
		DR1501	2 of 2
441–460	ELLVLLENERTLDYHDSNVK	DR0101	2 of 4
		DR0401	5 of 7
		DR0404	2 of 4
457–476	SNVKNLYEKVRSQLKNNAKE	DRB5	3 of 4
465–484	KVRSQLKNNAKEIGNGCFEF	DR1101	2 of 3
513–532	NREEIDGVKLESTRIYQILA	DR0701	1 of 7
521–540	KLESTRIYQILAIYSTVASS	DR0101	2 of 4
		DR0404	2 of 4

^aSequences based on H1N1/09 strain (accession: ACQ76318). ^bPeptides chosen for T-cell frequency analysis are shown in bold. ^c2009 H1N1 HA unique epitopes are in italics.