Immunohistochemical expression of DnaJ homolog subfamily B member 9 in immunoglobulin G4-related disease: a pilot study

DnaJ homolog subfamily B member 9 (DNAJB9) is a co-chaperone protein that governs the functions and integrity of cells. In immunoglobulin G4-related disease (IgG4-RD), DNAJB9 was shown to be upregulated in plasma cells, but its immunohistochemical expression has never been explored. This pilot study aims to investigate the immunohistochemical distribution and intensity of DNAJB9 in IgG4-RD tissue specimens.