Fig. 4

Histological evaluation of Thomsen–Friedenreich (T) antigen exposure in renal biopsy tissue showing its exposure in tubointerstitial lesions, and possible its interaction with IgM. a Staining with FITC-conjugated peanut lectin of a FFPE section from this patient demonstrated specific binding of peanut lectin to some tubular epithelial cells and some vascular endothelial cells, suggesting T-antigen exposure on these cells, whereas binding was not observed in a glomerulus (indicated as G). b The same staining of a FFPE section from a normal control showed negative results. A glomerulus was indicated as G. (c, d) Relative distribution of T-antigen exposure and IgM deposition. c Staining of fresh-frozen tissue with FITC-conjugated peanut lectin revealed positive staining of vascular endothelial cells adjacent to a glomerulus. d IF staining for IgM in an adjacent section to (c) revealed the deposition of IgM at the T-antigen-exposed site (indicated by blue arrows in c and d). Scale bars = 20.0 μm in (a)-(d)