Table 1.
Patient demographics.
Fig 1.
SARS CoV-2 specific antibody responses by severity of illness.
Comparison of the SARS-CoV-2 spike-specific and neutralization antibody titers between community and hospitalized patients is shown, Spike-specific IgG(A), IgA (B), IgM (C). Serum was collected at 2- and 6-months post-infection, and spike-specific responses were measured by ELISA. The neutralization antibodies were measured by pseudotype neutralization (PN) (D) and microneutralization (MN) (E) assays. Each symbol represents the SARS-CoV-2 spike- specific antibody responses of one individual, and the lines connect the paired samples at 2 and 6 months. The bars represent the geometric mean titers. A nonparametric paired t-test (Kruskal–Wallis), was used to compare 2- and 6-month samples (* = P<0.05, **P<0.005).
Fig 2.
SARS CoV-2 antibody responses by age and gender.
Comparison of the SARS-CoV-2 spike-specific and neutralization antibody titers according to age (A-C), gender (D-F) and the presence of comorbidities (G-I) is shown, Spike-specific IgG (A, D, G), PN (B, E, H) and MN (C, F, I). Each symbol represents the SARS-CoV-2 antibodies response from one individual with the circle symbol represents community dwelling patients, and the triangle represents hospitalized patients. The horizontal bars represent the mean T-cell response for each time point ± standard error of the mean. Statistical significance was determined by the non-parametric Kruskal-Wallis multiple comparisons test (* = P<0.05).
Fig 3.
SARS CoV-2 specific T-cell responses in community and hospitalized patients.
T-cell immune responses were evaluated by measuring the number of SARS-CoV-2 specific IFN-γ (A, D), IL-2 (B, E) and IFN-γ++ IL-2+ (C, F) secreting T-cells, (spot forming units) (SFU) after infection using the FluroSPOT assay. A-C; peripheral blood mononuclear cells (PBMC) were stimulated with peptide pools to measure the total (S1, S2, N, M), internal (N and M), and spike (S1 and S2) specific SARS-CoV-2 responses. D-F; the SARS CoV-2 specific S1, S2, M, N and inactivated SARS CoV-2 hCoV-19/Norway/Bergen-01/2020 virus (ISCoV-2). Each symbol represents the SARS-CoV-2 IFN-γ/IL-2 response (spot forming units (SFU) per 1×106 cells) after stimulation with virus spike antigen. The horizontal bars represent the mean IFN-γ response for each time point ± standard error of the mean. Statistical differences between different antigens or hospitalized and community dwelling subjects were determined by the nonparametric Kruskal–Wallis multiple comparisons test (* = P<0.05, ** = P<0.005).
Fig 4.
SARS CoV-2 specific T-cell responses by comorbidity.
The SARS-CoV-2 specific T-cell responses in peripheral blood mononuclear cells (PBMC) were determined by IFN-γ+, IL-2+, and IFN-γ++ IL-2+ in FluroSPOT in community and hospitalized patients who were SARS-CoV-2 confirmed, rt-PCR positive. The results are plotted according to the presence of comorbidities or no comorbidities. Each symbol represents the SARS-CoV-2 IFN-γ/IL-2 response (spot forming units (SFU) per 1×106 cells) after stimulation with virus spike antigen. The circle symbol represents community dwelling patients, and the triangle represents hospitalized patients. The horizontal bars represent the mean T-cell response for each time point ± standard error of the mean. Statistical significance was tested by the non-parametric Kruskal-Wallis multiple comparisons test (P<0.05), and no significant difference was found.
Fig 5.
Influence of age and gender on SARS CoV-2 specific T cells.
The SARS-CoV-2 specific IFN-γ responses in peripheral blood mononuclear cells (PBMC) were determined by IFN-γ+ (A,D), IL-2+ (B,E), and IFN-γ++ IL-2+ (C,F), in FluroSPOT in community and hospitalized patients who were SARS-CoV-2 confirmed, rt-PCR positive. The results are plotted according to age (A-C) and gender (D-F). Each symbol represents the SARS-CoV-2 IFN-γ/IL-2 response (spot forming units (SFU) per 1×106 cells) after stimulation with virus spike antigen. The circle symbol represents community dwelling patients, and the triangle represents the hospitalized patients. The horizontal bars represent the mean response for each time point ± standard error of the mean. Statistical significance was determined by the non-parametric Kruskal-Wallis multiple comparisons test (* = P<0.05, ** = P<0.005).