The recombinant chIL-7 in the culture medium was detected with Western blot as previously described (Wen et al., 2013 (link)) using Anti-Myc mAb (Santa Cruz Biotechnologies). For the intracellular chIL-7 detection, the transfected cells were lysed with lysis buffer (5 mM Tris-HCl, 25 mM KCl, 2 mM EGTA, 2 mM EDTA, 1% NP-40, 150 mM NaCl and protease inhibitors) and then subjected to Western blot described as above.