Figure 2. Kinetics of the antibody response to primary HCMV infection.

(A) Kinetics of the appearance of anti-pentamer (IgG-Pent), anti-gH/gL (IgG-gH/gL) and anti-gB (IgG-gB) antibodies in 46 subjects with primary HCMV infection. Shown are individual values and non-linear regression curves for the three specificities. P-values were calculated using the extra-sum-of square F test. (B) Kinetics of the mean HCMV serological response in the 46 patients’ sera. IgG-HCMV refers to HCMV lysate-specific IgG Arbitrary Units (AU); IgM-HCMV refers to HCMV lysate-specific IgM ratio; Nt-HELF and Nt-ARPE19 refer to neutralizing antibody (Neut Ab) titer on human embryonic lung fibroblasts (HELF) and epithelial (ARPE-19) cells, respectively; HCMV DNA refers to viral load in blood. (C) Correlation between IgG-pentamer antibody titers measured by ELISA and neutralizing antibody titers measured using ARPE-19. Values were obtained from sera collected <60 day post infection (filled diamonds) or >60 days post infection (empty diamonds). The regression coefficient (r²) is also shown. (D) Neutralizing antibody (Neut Ab) titers of sera from 3 patients (Pt.A, Pt.B, and Pt.C) were measured using ARPE-19. Sera were used either untreated or after absorption with the soluble pentameric complex, gH/gL dimer, or gB proteins from HCMV or with influenza A virus hemagglutinin (HA).