H2N2 live attenuated influenza vaccine is safe and immunogenic for healthy adult volunteers

Figures & data

Table 1. Demographic characteristics of study participants

Characteristics	Vaccine N = 28 (100%)	Placebo N = 10 (100%)
Gender
Male	16 (57.1)	7 (70)
Female	12 (42.9)	3 (30)
Race
White	28 (100)	10 (100)
Age (years)
Mean (SE)	28.0 (1.26)	26.2 (2.49)
Median	27.0	24.5
Range	18.0– 40.0	18.0–40.0

Figure 1. Study flow diagram.

Table 2. Subjects with reactogenicity and adverse events following vaccination

	Post dose 1 n; % (95% CI)		Post dose 2 n; % (95% CI)
Outcomes	Vaccine N=28	Placebo N=10	Vaccine N=28	Placebo N=10
Within 2 hours post-vaccination
Any adverse reaction	0; 0.0 (0.0; 12.1)	0; 0.0 (0.0; 27.8)	0; 0.0 (0.0; 12.1)	0; 0.0 (0.0; 27.8)
Within 7 d post-vaccination
Solicited reactions
Local reaction	4; 14.3 (5.7; 31.5)	2; 20.0 (5.7; 51.0)	0; 0.0 (0.0; 12.1)	0; 0.0 (0.0; 27.8)
Systemic reaction	13; 46.4 (29.5; 64.2)	4; 40.0 (16.8; 68.7)	9; 32.1 (17.9; 50.7)	2; 20.0 (5.7; 51.0)
Any	13; 46.4 (29.5; 64.2)	5; 50.0 (23.7; 76.3)	9; 32.1 (17.9; 50.7)	2; 20.0 (5.7; 51.0)
Solicited local reactions
Nose dryness	4; 14.3 (5.7; 31.5)	2; 20.0 (5.7; 51.0)	0; 0.0 (0.0; 12.1)	0; 0.0 (0.0; 27.8)
Solicited systemic reactions
Fatigue/malaise	1; 3.6 (0.6; 17.7)	0; 0.0 (0.0; 27.8)	0; 0.0 (0.0; 12.1)	0; 0.0 (0.0; 27.8)
Headache	2; 7.1 (2.0; 22.6)	0; 0.0 (0.0; 27.8)	2; 7.1 (2.0; 22.6)	1; 10.0 (1.8; 40.4)
Sore throat	3; 10.7 (3.7; 27.2)	4; 40.0 (16.8; 68.7)	5; 17.9 (7.9; 35.6)	1; 10.0 (1.8; 40.4)
Vomiting	1; 3.6 (0.6; 17.7)	0; 0.0 (0.0; 27.8)	0; 0.0 (0.0; 12.1)	0; 0.0 (0.0; 27.8)
Temperature	12; 42.9 (26.5; 60.9)	1; 10.0 (1.8; 40.4)	4; 14.3 (5.7; 31.5)	0; 0.0 (0.0; 27.8)
Adverse events
Worst grade – mild	22; 78.6 (60.5; 89.8)	9; 90.0 (59.6; 98.2)	25; 89.3 (72.8; 96.3)	7; 70.0 (39.7; 89.2)
Worst grade – moderate	1; 3.6 (0.6; 17.7)	1; 10.0 (1.8; 40.4)	3; 10.7 (3.7; 27.2)	0; 0.0 (0.0; 27.8)
Worst grade – severe	0; 0.0 (0.0; 12.1)	0; 0.0 (0.0; 27.8)	0; 0.0 (0.0; 12.1)	0; 0.0 (0.0; 27.8)
Any event	22; 78.6 (60.5; 89.8)	9; 90.0 (59.6; 98.2)	25; 89.3 (72.8; 96.3)	7; 70.0 (39.7; 89.2)
Any treatment–related event	16; 57.1 (39.1; 73.5)	5; 50.0 (23.7; 76.3)	19; 67.9 (49.3; 82.1)	4; 40.0 (16.8; 68.7)
Any serious adverse event	0; 0.0 (0.0; 12.1)	0; 0.0 (0.0; 27.8)	0; 0.0 (0.0; 12.1)	0; 0.0 (0.0; 27.8)

CI, 95% confidence interval as calculated by Wilson test.

Table 3. Subjects with adverse events following vaccination

	Post dose 1 n; % (95% CI)		Post dose 2 n; % (95% CI)
Outcomes	Vaccine N=28	Placebo N=10	Vaccine N= 28	Placebo N=10
Ear Congestion	1; 3.6 (0.6; 17.7)	0; 0.0 (0.0; 27.8)	0; 0.0 (0.0; 12.1)	0; 0.0 (0.0; 27.8)
Fatigue	0; 0.0 (0.0; 12.1)	0; 0.0 (0.0; 27.8)	1; 3.6 (0.6; 17.7)	0; 0.0 (0.0; 27.8)
Pyrexia	2; 7.1 (2.0; 22.6)	1; 10.0 (1.8; 40.4)	0; 0.0 (0.0; 12.1)	0; 0.0 (0.0; 27.8)
Periodontitis	1; 3.6 (0.6; 17.7)	0; 0.0 (0.0; 27.8)	0; 0.0 (0.0; 12.1)	0; 0.0 (0.0; 27.8)
ALT elevation	1; 3.6 (0.6; 17.7)*	0; 0.0 (0.0; 27.8)	3; 10.7 (3.7; 27.2)*	0; 0.0 (0.0; 27.8)
AST elevation	1; 3.6 (0.6; 17.7)	0; 0.0 (0.0; 27.8)	2; 7.1 (2.0; 22.6)	0; 0.0 (0.0; 27.8)
Bicarbonate elevation	3; 10.7 (3.7; 27.2)	2; 20.0 (5.7; 51.0)	2; 7.1 (2.0; 22.6)	0; 0.0 (0.0; 27.8)
Bilirubin elevation	2; 7.1 (2.0; 22.6)	1; 10.0 (1.8; 40.4)*	2; 7.1 (2.0; 22.6)*	1; 10.0 (1.8; 40.4)
Glucose elevation	1; 3.6 (0.6; 17.7)	1; 10.0 (1.8; 40.4)	3; 10.7 (3.7; 27.2)*	1; 10.0 (1.8; 40.4)
Calcium elevation	2; 7.1 (2.0; 22.6)	0; 0.0 (0.0; 27.8)	2; 7.1 (2.0; 22.6)	1; 10.0 (1.8; 40.4)
Lymphocyte count elevation	12; 42.9 (26.5; 60.9)	1; 10.0 (1.8; 40.4)	19; 67.9 (49.3; 82.1)	6; 60 (31.3; 83.2)
Monocyte count elevation	5; 17.9 (7.9; 35.6)	1; 10.0 (1.8; 40.4)	6; 21.4 (10.2; 39.5)	1; 10.0 (1.8; 40.4)
Neutrophil count decreased	9; 32.1 (17.9; 50.7)	5; 50.0 (23.7; 76.3)	10; 35.7 (20.7; 54.2)	4; 40.0 (16.8; 68.7)
RBC sedimentation rate increased	4; 14.3 (5.7; 31.5)	1; 10.0 (1.8; 40.4)	0; 0.0 (0.0; 12.1)	0; 0.0 (0.0; 27.8)

*denotes moderate grade AE in one subject; all the other events were mild; CI, 95% confidence interval as calculated by Wilson test; ALT - Alanine aminotransferase; AST - Aspartate aminotransferase; RBCs – red blood cells.

Table 4. Detection of influenza H2N2 virus in subjects vaccinated with H2N2 LAIV

	Vaccination																		Revaccination
	1 dpv			2 dpv			3 dpv			4 dpv			5–6 dpv			29 (1) dpv			30 (2) dpv		31–34 (3–6) dpv
ID#	PCR nose	PCR throat	Eggs	PCR nose	PCR throat	Eggs	PCR nose	PCR throat	Eggs	PCR nose	PCR throat	Eggs	PCR nose	PCR throat	Eggs	PCR nose	PCR throat	Eggs	PCR nose	PCR throat	Eggs	PCR nose	PCR throat	Eggs	Virus detected
02	+	−	−	+	−	−	+	−	−	−	−	−	−	−	−	−	−	−	−	−	ND	−	−	−	+
04	+	−	−	+	−	−	−	−	−	−	−	−	−	−	−	+	−	−	−	−	ND	−	−	−	+
07	+	−	−	+	+	−	−	−	−	−	−	−	−	−	−	+	−	−	−	−	ND	−	−	−	+
09	−	−	−	−	−	−	−	−	−	−	−	−	−	−	−	−	−	−	−	−	ND	−	−	−	−
10	−	−	−	−	−	−	−	−	−	−	−	−	−	−	−	+	−	−	−	−	ND	−	−	−	+
11	+	−	−	−	−	−	−	−	−	−	−	−	−	−	−	+	−	−	−	−	ND	−	−	−	+
14	+	−	+	+	−	−	+	−	−	−	−	−	−	−	−	−	−	−	−	−	ND	−	−	−	+
15	+	−	−	+	−	−	−	−	−	−	−	−	−	−	−	+	−	+	+	−	ND	−	−	−	+
18	+	−	+	+	−	−	+	−	−	+	−	−	−	−	−	+	−	−	−	−	ND	−	−	−	+
20	+	−	+	+	+	−	+	+	−	+	+	−	−	−	−	ND	ND	ND	ND	ND	ND	ND	ND	ND	+
21	−	−	−	−	−	−	−	−	−	−	−	−	−	−	−	−	−	−	−	−	ND	−	−	−	−
23	+	−	+	+	−	−	−	−	−	−	−	−	−	−	−	+	−	−	−	−	ND	−	−	−	+
25	+	−	−	+	−	−	+	−	−	+	−	−	−	−	−	+	−	−	−	−	ND	−	−	−	+
26	+	−	+	+	+	−	−	−	−	−	−	−	−	−	−	+	−	+	−	−	ND	−	−	−	+
27	+	−	−	−	−	−	−	−	−	−	−	−	−	−	−	+	−	+	−	−	ND	−	−	−	+
31	−	−	−	−	−	−	−	−	−	−	−	−	−	−	−	−	−	−	−	−	ND	−	−	−	−
32	+	−	+	−	−	−	−	−	−	−	−	−	−	−	−	+	−	−	−	−	ND	−	−	−	+
36	+	−	+	−	−	−	−	−	−	−	−	−	−	−	−	+	−	+	−	−	ND	−	−	−	+
37	+	−	−	−	−	−	−	−	−	−	−	−	−	−	−	+	+	−	−	−	ND	−	−	−	+
38	+	−	+	−	−	−	−	−	−	−	−	−	−	−	−	+	−	−	−	−	ND	−	−	−	+
39	+	−	−	−	−	−	−	−	−	−	−	−	−	−	−	+	+	−	−	−	ND	−	−	−	+
41	+	−	−	−	−	−	−	−	−	−	−	−	−	−	−	+	−	+	−	−	ND	−	−	−	+
42	+	−	+	+	−	+	−	−	−	−	−	−	−	−	−	+	−	+	+	−	ND	−	−	−	+
46	+	−	+	−	−	−	−	−	−	−	−	−	−	−	−	+	−	+	−	−	ND	−	−	−	+
49	+	−	−	−	−	−	−	−	−	−	−	−	−	−	−	+	−	−	−	−	ND	−	−	−	+
50	+	−	+	−	−	−	−	−	−	−	−	−	−	−	−	+	−	+	−	−	ND	−	−	−	+
52	−	−	−	−	−	−	−	−	−	−	−	−	−	−	−	−	−	−	−	−	ND	−	−	−	−
54	−	−	−	−	−	−	−	−	−	−	−	−	−	−	−	−	−	−	−	+	ND	−	−	−	+
Total (%)	22 (78.6)	0 (0.0)	11 (39.3)	11 (39.3)	3 (10.7)	1 (3.6)	5 (17.9)	1 (3.6)	0 (0.0)	3 (10.7)	1 (3.6)	0 (0.0)	0 (0.0)	0 (0.0)	0 (0.0)	20 (74.1)	2 (7.4)	8 (29.6)	2 (7.4)	1 (3.7)	ND	0 (0.0)	0 (0.0)	0 (0.0)	24 (85.7)

dpv – days post vaccination; ND – not done.

Table 5. Proportion of subjects with ≥4-fold rise in antibody titers after vaccination with H2N2 LAIV or Placebo

		After 1 dose (Day 28) LAIV: N=27 placebo: N=9		After 2 doses (Day 56) LAIV: N=27 placebo: N=7		After 2 doses (Day 112) LAIV: N=25 placebo: N=7		Cumulative conversions
Assay	Test article	n (%)	95% CI	n (%)	95% CI	n (%)	95% CI	n (%)	95% CI
HAI: serum Ab	LAIV	5 (18.5)	8.2–36.7	9 (33.3)	18.6–52.2	15 (60.0)^1	40.7–76.6	16 (59.3)	40.7–75.5
	Placebo	0	0.0–29.9	0	0.0–34.5	0	0.0–34.5	0	0.0–29.9
MN: serum Ab	LAIV	8 (29.6)	15.9–48.5	12 (44.4)^2	27.6–62.7	12 (48.0)	26.7–62.9	16 (59.3)	40.7–75.5
	Placebo	0	0.0–29.9	0	0.0–34.5	0	0.0–34.5	0	0.0–29.9
ELISA: serum IgA	LAIV	2 (7.4)	2.1–23.4	14 (51.9)^3	34.0–69.3	12 (48.0)^4	30.0–66.5	14 (51.9)	34.0–69.3
	Placebo	0	0.0–29.9	0	0.0–34.5	0	0.0–34.5	0	0.0–29.9
ELISA: serum IgG	LAIV	0	0.0–12.5	1 (3.7)	0.7–18.3	2 (8.0)	2.2–25.0	2 (7.4)	2.1–23.4
	Placebo	0	0.0–29.9	0	0.0–34.5	0	0.0–34.5	0	0.0–29.9
ELISA: nasal IgA	LAIV	6 (22.2)	10.6–40.8	11 (40.7)	24.5–59.3	n/a	n/a	13 (48.1)	30.7–66.0
	Placebo	0	0.0–29.9	0	0.0–34.5	n/a	n/a	0	0.0–29.9
ELISA: salivary IgA	LAIV	3 (11.1)	3.9–28.1	9 (33.3)	18.6–52.2	n/a	n/a	12^† (44.4)	27.6–62.7
	Placebo	0	0.0–29.9	0	0.0–34.5	n/a	n/a	0	0.0–29.9
Cumulative conversions	LAIV	15 (55.6)^5	37.3–72.4	23 (85.2)^6	67.5–94.1	21 (84.0)^7	65.3–93.6	23 (85.2)	67.5–94.1
	Placebo	0	0.0–29.9	0	0.0–34.5	0	0.0–34.5	0	0.0–29.9

CI, 95% confidence interval as calculated by Wilson test; n/a – not applicable (nasal swab and saliva samples were not collected at Day 112); HAI – hemagglutination inhibition assay; MN – microneutralization; ELISA - Enzyme-linked immunosorbent assay; Ab – antibody;

^†2 subjects had 4-fold rises in salivary IgA antibody titer at Day 56 compared to Day 28, and only 2-fold rise at Day 56 compared to Day 0;

¹percent of subjects with HAI Ab conversions 84 d after 2nd vaccination is significantly higher in LAIV group than in Placebo group (Fisher exact (2–tailed) p = 0.008);

²percent of subjects with MN Ab conversions 28 d after 2nd vaccination is significantly higher in LAIV group than in Placebo group (Fisher exact (2–tailed) p = 0.036);

³percent of subjects with serum IgA conversions 28 d after 2nd vaccination is significantly higher in LAIV group than in Placebo group (Fisher exact (2–tailed) p = 0.026);

⁴percent of subjects with serum IgA conversions 84 d after 2nd vaccination is significantly higher in LAIV group than in Placebo group (Fisher exact (2–tailed) p = 0.029);

⁵cumulative percent of subjects with Ab conversions is significantly higher in LAIV group than in Placebo group (Fisher exact (2–tailed) p = 0.005);

⁶cumulative percent of subjects with Ab conversions 28 d after 2nd vaccination is significantly higher in LAIV group than in Placebo group (Fisher exact (2–tailed) p = 0.0001);

⁷cumulative percent of subjects with Ab conversions 56 d after 2nd vaccination is significantly higher in LAIV group than in Placebo group (Fisher exact (2–tailed) p = 0.0001);

Table 6. Geometric mean titers of serum and local antibodies in volunteers vaccinated with H2N2 LAIV

		Reverse GMTs				GMT fold changes*
Assay	Test article	Day 0 LAIV: N=27 placebo: N=9	Day 28 LAIV: N=27 placebo: N=9	Day 56 LAIV: N=27 placebo: N=7	Day 112 LAIV: N=25 placebo: N=7	Day 28 / Day 0	Day 56 / Day 0	Day 112 / Day 0
HAI: serum Ab	LAIV	2.5	3.5	5.1	7.4	1.4^1	2.0^2	3.0^3
	Placebo	2.5	2.5	3.0	2.8	1.0	1.2	1.1
MN: serum Ab	LAIV	5.4	10.5	13.6	14.7	1.9^4	2.5^5	2.7^6
	Placebo	6.8	8.6	8.2	9.0	1.3	1.2	1.3
ELISA: serum IgA	LAIV	12.7	16.8	29.6	33.8	1.3^7	2.3^8	2.4^9
	Placebo	13.7	16.0	14.5	13.1	1.2	0.9	0.8
ELISA: serum IgG	LAIV	10.9	11.8	11.8	14.3	1.1	1.1	1.3^10
	Placebo	12.7	13.7	13.1	14.5	1.1	1.0	1.1
ELISA: nasal IgA	LAIV	3.5	4.8	8.6	n/a	1.4	2.5^11	n/a
	Placebo	10.9	6.9	8.8	n/a	0.6	1.0	n/a
ELISA: salivary IgA	LAIV	3.1	3.3	6.7	n/a	1.1	2.2^12	n/a
	Placebo	3.7	3.2	4.4	n/a	0.9	1.2	n/a

GMT – geometric mean titer; HAI – hemagglutination inhibition assay; MN – microneutralization; ELISA - Enzyme-linked immunosorbent assay; Ab – antibody;

*GMT fold changes are calculated only for those subjects who was available at indicated days;

¹GMT of HAI Ab after 1st vaccination is significantly higher than GMT before vaccination (Wilcoxon Matched Pairs Test: p = 0.028);

²GMT of HAI Ab 28 d after 2nd vaccination is significantly higher than GMT before vaccination (Wilcoxon Matched Pairs Test: p = 0.0007);

³GMT of HAI Ab 84 d after 2nd vaccination is significantly higher than GMT before vaccination (Wilcoxon Matched Pairs Test: p = 0.0002);

⁴GMT of MN Ab after 1st vaccination is significantly higher than GMT before vaccination (Wilcoxon Matched Pairs Test: p = 0.0002);

⁵GMT of MN. Ab 28 d after 2nd vaccination is significantly higher than GMT before vaccination (Wilcoxon Matched Pairs Test: p = 0.00002);

⁶GMT of MN. Ab 84 d after 2nd vaccination is significantly higher than GMT before vaccination (Wilcoxon Matched Pairs Test: p = 0.00001);

⁷GMT of serum IgA after 1st vaccination is significantly higher than GMT before vaccination (Wilcoxon Matched Pairs Test: p = 0.019);

⁸GMT of serum IgA 28 d after 2nd vaccination is significantly higher than GMT before vaccination (Wilcoxon Matched Pairs Test: p = 0.00002);

⁹GMT of serum IgA 84 d after 2nd vaccination is significantly higher than GMT before vaccination (Wilcoxon Matched Pairs Test: p = 0.0005);

¹⁰GMT of serum IgG 84 d after 2nd vaccination is significantly higher than GMT before vaccination (Wilcoxon Matched Pairs Test: p = 0.019);

¹¹GMT of nasal IgA 28 d after 2nd vaccination is significantly higher than GMT before vaccination (Wilcoxon Matched Pairs Test: p = 0.003);

¹²GMT of salivary IgA 28 d after 2nd vaccination is significantly higher than GMT before vaccination (Wilcoxon Matched Pairs Test: p = 0.0003).

Table 7. GMTs in subjects with ≥4 -fold rises in antibody titers after 2 doses of H2N2 LAIV

	After 2 doses, Day 56				After 2 doses, Day 112
		Reverse GMTs				Reverse GMTs
Assay	n	Day 0	Day 56	GMT rise	n	Day 0	Day 112	GMT rise
HAI: serum Ab	9	2.5	13.6	5.4	15	2.5	13.2	5.3
MN: serum Ab	12	5.0	20.0	4.0	12	5.0	20.0	4.0
ELISA: serum IgA	14	8.8	41.0	4.7	12	9.0	47.9	5.3
ELISA: nasal IgA	13	1.9	12.9	6.8	n/a	n/a	n/a	n/a
ELISA: salivary IgA	12	3.6	14.3	4.0	n/a	n/a	n/a	n/a

GMT – geometric mean titer; HAI – hemagglutination inhibition assay; MN – microneutralization; ELISA - Enzyme-linked immunosorbent assay; Ab – antibody; n/a – not applicable (nasal swab and saliva samples were not collected at Day 112).

Table 8. T cell immune responses in volunteers vaccinated with H2N2 LAIV or placebo

		Percent of subjects with significant increases* in virus–specific memory T cells
		CD4+		CD4+ Tcm**		CD4+ Tеm**		CD8+		CD8+ Tcm		CD8+ Tеm		Total
Time points	Test article	n (%)	95% CI	n (%)	95% CI	n (%)	95% CI	n (%)	95% CI	n (%)	95% CI	n (%)	95% CI	n (%)	95% CI
Day 6 / Day 0	LAIV (n = 27)	1 (3.7)	0.7–18.3	0	0.0–12.5	0	0.0–12.5	3 (11.1)	3.9–28.1	0	0.0–12.5	0	0.0–12.5	3 (11.1)	3.9–28.1
	Placebo (n = 10)	0	0.0–27.8	0	0.0–27.8	0	0.0–27.8	0	0.0–27.8	0	0.0–27.8	0	0.0–27.8	0	0.0–27.8
Day 28 / Day 0	LAIV (n = 27)	2 (7.4)	2.1–23.4	2 (7.4)	2.1–23.4	3 (11.1)	3.9–28.1	3 (11.1)	3.9–28.1	2 (7.4)	2.1–23.4	3 (11.1)	3.9–28.1	6 (22.2)	10.6–40.8
	Placebo (n = 10)	0	0.0–27.8	0	0.0–27.8	0	0.0–27.8	0	0.0–27.8	0	0.0–27.8	0	0.0–27.8	0	0.0–27.8
Day 56 / Day 0	LAIV (n = 27)	3 (11.1)	3.9–28.1	3 (11.1)	3.9–28.1	1 (3.7)	0.7–18.3	1 (3.7)	0.7–18.3	1 (3.7)	0.7–18.3	3 (11.1)	3.9–28.1	6 (22.2)	10.6–40.8
	Placebo (n = 7)	0	0.0–34.5	0	0.0–34.5	0	0.0–34.5	0	0.0–34.5	0	0.0–34.5	0	0.0–34.5	0	0.0–34.5
Day 112 / Day 0	LAIV (n = 25)	5 (20.0)	8.9–39.1	1 (4.0)	0.7–19.5	2; (8.0)	2.2–25.0	3 (12.0)	4.2–30.0	3 (12.0)	4.2–30.0	9 (36.0)	20.2–55.5	11 (44.0)	26.7–62.9
	Placebo (n = 7)	0	0.0–34.5	0	0.0–34.5	0	0.0–34.5	0	0.0–34.5	0	0.0–34.5	0	0.0–34.5	0	0.0–34.5
TOTAL	LAIV (n = 27)	6 (22.2)	10.6–40.8	4 (14.8)	5.9–32.5	4 (14.8)	5.9–32.5	6 (22.2)	10.6–40.8	4 (14.8)	5.9–32.5	12 (44.4)	27.6–62.7	15 (55.6)	37.3–72.4
	Placebo (n = 10)	0	0.0–27.8	0	0.0–27.8	0	0.0–27.8	0	0.0–27.8	0	0.0–27.8	0	0.0–27.8	0	0.0–27.8

*More than Placebo mean value plus 3 Standard Deviations; CI, 95% confidence interval as calculated by Wilson test;

**Tcm – central memory T cells; Tem – effector memory T cells.

Table 9. Summary on individual data on antibody and cellular immune responses in subjects vaccinated with H2N2 LAIV

	Antibody (Ab) responses							Cell mediated immune (CMI) responses
ID#	HAI	MN	serum IgG	serum IgA	nasal IgA	salivary IgA	Any	CD4+	CD8+	CD4 Tcm	CD4 Tem	CD8 Tcm	CD8 Tem	Any	Either Ab or CMI response
02	+	+		+	+		+								+
04		+			+	+	+					+	+	+	+
07	+	+		+		+	+	+	+			+	+	+	+
09									+					+	+
10	+	+			+	+	+	+	+	+	+	+	+	+	+
11		+			+		+								+
14	+	+		+	+	+	+	+					+	+	+
15	+	+			+	+	+								+
18	+		+	+	+	+	+						+	+	+
21													+	+	+
23	+	+					+								+
25		+		+	+	+	+								+
26	+	+			+	+	+			+	+		+	+	+
27						+	+								+
31
32	+	+	+	+	+		+								+
36	+	+		+			+								+
37	+			+			+								+
38	+	+		+			+	+		+				+	+
39	+			+	+		+						+	+	+
41		+					+				+		+	+	+
42				+	+		+	+		+			+	+	+
46	+	+					+		+		+	+	+	+	+
49	+			+	+	+	+	+	+				+	+	+
50	+			+		+	+		+					+	+
52
54		+		+		+	+								+
Total	16	16	2	14	13	12	23	6	6	4	4	4	12	15	25
	(59.3%)	(59.3%)	(7.4%)	(51.9%)	(48.1%)	(44.4%)	(85.2%)	(22.2%)	(22.2%)	(14.8%)	(14.8%)	(14.8%)	(44.4%)	(55.6%)	(92.6%)

GMT – geometric mean titer; HAI – hemagglutination inhibition assay; MN – microneutralization; Tcm – central memory T cells; Tem – effector memory T cells.

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