TGFB1 and pemphigus foliaceus: Next, to target TGF‐β directly and inhibit BLM‐induced PF, a Myc‐tagged fusion protein consisting of an extracellular truncated domain of TGBβ‐Receptor 2 fused to IgG Fc domain was constructed, which was stably expressed in RAW264.7 cells and named TGFRcFc‐M.