Persistence of Anti-SARS-CoV-2 Spike IgG Antibodies Following COVID-19 Vaccines

Figures & data

Table 1 Number of Samples Collected from Vaccinated Individuals at Different Time Points

Time Point	Number of Samples
Baseline	231
Post-prime	232
Post-boost	127
6 Months	47
12 Months	4
Post-3rd dose	25
Convalescent	119
Total tested samples	785

Table 2 Demographic and Clinical Factors Influencing Vaccine-Induced Immune Responses

		Pre-Vaccine	Post-Prime	Post-Boost	6 Months
		Mean IgG Titer (SD)	Mean IgG Titer (SD)	Mean IgG Titer (SD)	Mean IgG Titer (SD)
Gender	Males	2,090 (17,118) n=87	27,965 (55,529) n=49	138,280 (356,928) n=31	25,237 (33,681) n=18
	Female	1,600 (10,807) n=83	13,909 (30,658) n=80	301,455 (517,115) n=43	20,246 (31,907) n=22
	p-value	0.8	0.06	0.13	0.6
Age	<38.5Y	2,024 (15,499) n=106	26,754 (51,442) n=61	303,806 (532,040) n=24	14,976 (16,559) n=9
	>38.5Y	1,264 (10,942) n=80	9,847 (26,368) n=91	247,906 (493,307) n=53	24,673 (35,876) n=31
	p-value	0.7	0.01	0.7	0.4
BMI	<30	1,325 (9,947) n=97	18,146 (39,092) n=87	315,340 (560,716) n=42	25,373 (35,086) n=21
	>30	7,319 (34,000) n=22	5,756 (18,413) n=18	75,331 (63,027) n=12	35,591 (41,638) n=7
	p-value	0.13	0.23	0.15	0.53
Diabetes	No	1,688 (13,568) n=191	14,829 (37,847) n=135	274,216 (523,720) n=69	20,837 (30,677) n=38
	Yes	194 (529) n=16	13,141 (30,634) n=12	77,866 (82,617) n=4	NA
	p-value	0.76	0.9	0.46	NA
Hypertension	No	1,722 (10,620) n=198	15,524 (35,818) n=127	230,932 (373,789) n=64	23,845 (34,251) n=34
	Yes	11 (46) n=20	4,710 (8949) n=23	382,148 (736,519) n=13	14,823 (18,904) n=6
	p-value	0.57	0.19	0.36	0.53
Asthma	No	1,168 (11,505) n=95	15,045 (37,920) n=135	284,100 (522,306) n=71	22,318 (33,475) n=37
	Yes	6,993 (26,163) n=14	2,428 (2128) n=15	51,743 (25,788) n=6	24,635 (24,288) n=3
	p-value	0.1	0.2	0.28	0.9

Figure 1 Antibody responses post-COVID-19 vaccines.

Notes: (A) IgG induced by COVID-19 vaccination was evaluated in serum samples of non-infected people at six time points: pre-vaccine (baseline), post-prime, post-boost, 6 months, 1 year, and 3 weeks post-third dose. (B) Antibody responses are shown as per type of vaccine: AZ1222: brown symbols and, BNT162b2: pink symbols. Data in A and B are shown in comparison to non-vaccinated COVID-19 convalescent cases (grayed circles). (C) Neutralizing activity of COVID-19 vaccine-induced antibodies were determined. Horizontal lines represent means with SEM.

Figure 2 Impact of pre-infection and interval duration on antibody responses to COVID-19 vaccines.

Notes: (A) IgG titers in pre-infected vaccinated individuals (shown as red symbols) were compared to non-infected vaccinated individuals (shown as blue symbols). (B) IgG titers according to the duration of interval between prime and boost. (C) A correlation between the number of days in the interval and the IgG titers; Spearman r=0.3. Horizontal lines represents mean with SEM.