Fig. 1From: Bruton’s tyrosine kinase is a possible therapeutic target in microscopic polyangiitisBtk phosphorylation in B lymphocytes derived from lymph node cells and PBMCs in tirabrutinib-administered rats. Various doses of tirabrutinib or vehicle were orally administered to SD rats daily for 4 weeks. Rats underwent laparotomy under anesthesia and were sacrificed by exsanguination 24 h after the final dosing. Lymph node cells (a) and PBMCs (b) were treated with phosphatase inhibitor cocktail 2, stimulated by 3 mM H2O2 for 10 min at 37 °C, and stained using Btk-pY223 antibodies. The MFI of Btk-pY223 in B lymphocytes (identified by gating CD45RA+ and CD3− cells) was analyzed by FCMBack to article page