Legends
Figure 1: Level of anti-Spike IgG antibodies (A ) and
(B ) presence of SARS-CoV-2 neutralizing antibodies (NA) in sera
from healthy individuals (blue, controls) and in patients receiving
drugs that inhibit tumor necrosis factor (red, anti-TNF). The horizontal
lines indicate the cut-off values of the IgG enzyme immunoassay (25
BAU/ml) and virus neutralization assay (reciprocal titer
>10), respectively. Where appropriate, the geometric mean
and standard deviation of virus-neutralizing antibody titers were
calculated. Individual samples were collected on the day of the fourth
or fifth SARS-CoV-2 vaccination (0 days, empty triangle and circles) and
one week later (7 days, filled triangle and circles). Details of the
vaccination schedule used are provided in Table 1. Titers were
determined with a Vero cell-based virus neutralization assay using a
member of the 2020 lineage B.1.513, and previous or current SARS-CoV-2
variants Alpha (B.1.1.7), Delta (B.1.617.2), and Omicron (BA.1.17.2,
BA.2, BA.5.2.1, BQ.1.1.1, XBB.1.5) as antigens. These strains were
isolated by us under BSL-3 conditions from patient material and
characterized by whole genome sequencing. The x-fold increase in
geometric mean titer between day 0 and day 7 is shown in green for
anti-TNF patients. In addition, the x-fold decrease (รท) in geometric
mean titers between controls and anti-TNF patients is reported for day 7
after booster vaccination. Anti-nucleoprotein IgG was detected in one
subject in the control group, indicating that she had undergone
SARS-CoV-2 infection. Her results are therefore presented separately
(blue triangle) and not included in the calculation of the geometric
mean titer of the control group.
Table 1: Characteristics of four patients treated with
anti-tumor necrosis factor (TNF) agents and three healthy control
subjects. All individuals are female. Previous SARS-CoV-2 vaccinations
are indicated in order of application. Sera were collected on the day of
a booster vaccination with mRNA vaccine adapted to Omicron BA.4 and BA.5
and 7 days later. IgG avidity was measured by immunoblot. Based on the
comparison of band intensities of the avidity reagent-treated sample
with the untreated sample, IgG avidity is classified as low, medium, and
high. The intensity ratios measured are also listed. The presence of
anti-nucleoprotein IgG (data not shown) in the immunoblot of subject #5
indicates that she had COVID-19. Abbreviations: messenger RNA-based
SARS-CoV-2 vaccines, BNT162b2 and mRNA-1273; replication-deficient
chimpanzee adenoviral vector containing the SARS-CoV-2 spike protein,
ChAdOx1; healthy control, HC; Rheumatoid arthritis, RA; receptor-binding
domain of the spike protein, RBD; subunit 1 of the spike protein, S1;
wild type, wt.