Fig 1: Assessment of specificity of anti-SATB1 and anti-SATB2 antibodies using Western blot (a–c) and immunohistochemistry (d–e) analyses. Western blot results following incubation with anti-SATB1 (a), anti-SATB2 (b), or anti-DDK Tag (c) antibodies (lane 1, molecular weight marker; lane 2, negative control lysate; lane 3, SATB1; and lane 4, SATB2-overexpressing mammalian HEK293T lysate). Note specific binding of antibodies to their respective lysates. Immunohistochemistry results following staining with anti-SATB1 (d, f) and anti-SATB2 (e, g) antibodies in rectum (d, e) and tonsil (f, g). Note strong nuclear immunoreactivity in a subset of lymphocytes following staining with anti-SATB1 antibody both in rectum and tonsil and absence of nuclear immunoreactivity in glandular epithelium of rectum. Staining with anti-SATB2 displays strong nuclear positivity in rectum glandular cells, while lymphoid cells are mainly negative