Histological analysis and quantification of fibrosis.
INFILTRATION, INFILTRATES
Atria were fixed and sectioned for histological analysis of inflammatory infiltrates by staining for hematoxylin and eosin (MilliporeSigma), activated T lymphocytes (CD3, ab16669, Abcam; CD4, ab237722, Abcam), macrophage infiltration/polarization (CD68, ab125212, Abcam; CD163, ab182422, Abcam), and neutrophil infiltration (CD11b, ab133357, Abcam). Hematoxylin and eosin staining was quantified using the ImageJ color deconvolution plugin (