Figure 2.

Cardiac SARS-CoV-2 infection was not associated with increased immune cell infiltration. (A) The previously published ‘Heart Cell Atlas’¹⁴ served as single-cell RNA-sequencing dataset to generate a signature matrix using CibersortX from left ventricular tissue originated cells. Digital cytometry was performed, applying the generated signature matrix to our MACE-RNA-seq data by CibersortX. Cell fractions were estimated for each individual case. Comparing the immune cell fractions between cases with (n = 10) and without (n = 10) cardiac infection, no significant differences were determined using Mann–Whitney U test. Cell fractions are depicted as Tukey-style box plots with median and inter-quartile range without outliers. (B) The number of positively stained immune cells per mm² is displayed. Cases without cardiac infections (n = 46) are depicted in white, whereas cases with cardiac infection (n = 41) are depicted in red. The patient groups were compared using Mann–Whitney U test revealing no significant differences. Data are depicted as Tukey-style box plots with median and inter-quartile range without outliers. Representative staining of immune cells in cardiac tissue is displayed. On the left panel, the CD45R0 staining for Case 65, quantified as 15.1 cells per mm², is shown. The middle panel depicts the CD3 staining for Case 21 (7.4 cells/mm²). For Case 47, the CD68 staining is shown on the right panel (14.7 cells/mm²). Magnifications are displayed below for each case.