Figure 1.
Productive but limited SARS-CoV-2 infection of human islet cell populations
(A) Left: gating strategy for identification of α (GCG+), β (INS+), and “other” (GCG−INS−) cells; adjacent plots depict SARS-CoV-2 NP staining of the indicated subsets in 48-h mock- and SARS-CoV-2-infected samples. Right: frequencies of SARS-CoV-2 NP+ islet cell subsets (n = 7 donors).
(B) SARS-CoV-2 infection of all islet cells and donor stratification according to higher (>2.5% of total cells) and lower (<2.5%) extent of infection.
(C) Infectious virus titers in TCS (initial inoculum, 4 × 104 plaque-forming units (PFUs)/mL; 48-h culture; dotted line, limit of detection [LOD] = 67 PFU/mL; n = 6 donors).
(D) SARS-CoV-2 infection of islet cell subsets after 48-h and 120-h culture (n = 4 donors).
(E and F) Quantification of secreted proteins in UV-inactivated TCS of 48-h mock- or SARS-CoV-2-infected samples (NPX, normalized protein expression; n = 6 donors).
(G) Gating strategy for distinction of live and dead islet cells.
(H) Frequencies of live and dead SARS-CoV-2 NP+ islet cell subsets (48-h culture, n = 4 donors).
(I) Survival of islet cells distinguished according to infection condition and absence/presence of viral NP (n = 4 donors).
(J) INS expression levels (geometric mean of fluorescence intensity [GMFI]) by NP− and NP+ beta cells were normalized to respective INS GMFI values in donor-matched mock-infected cultures (n = 6 donors). All summary bar diagrams represent mean ± SD and scatter for indicated number of donors; statistical analyses were conducted by paired t test or repeated measures ANOVA with Tukey’s multiple comparisons (asterisks) or non-parametric Friedman test (hashtags) where applicable (∗ or #, p < 0.05; ∗∗ or ##, p < 0.01; ∗∗∗, p < 0.001).
All summary bar diagrams represent mean ± SD and scatter for the indicated number of donors; statistical analyses were conducted by paired t test or repeated-measures ANOVA with Tukey’s multiple comparisons where applicable (#, non-parametric Friedman test).