Reactive oxygen species involved in CT26 immunogenic cell death induced by Clostridium difficile toxin B

• The first report about molecular mechanism of immunogenic cell death induced by rTcdB.
• Reactive oxygen species is involved in rTcdB induced apoptosis and autophagy.
• Diphenylene iodonium and Antimycin A inhibit immunogenic cell death induced by rTcdB.
• N-acetyl cysteine does not inhibit immunogenic cell death induced by rTcdB.

Immunogenic cell death (ICD) is a new concept appeared in recent years. Despite growing interests of research on ICD, the circumstances that trigger immune responses against dying tumor cells remain largely unknown. It was demonstrated that recombinant Clostridium difficile toxin B (rTcdB) can induce ICD in intoxicated cells, but its mechanism remains unclear. This work aims at exploring whether reactive oxygen species (ROS) involved in rTcdB induced ICD using the chemical agent N-acetyl cysteine (NAC), diphenylene iodonium (DPI) and Antimycin A (Anti.A). The results suggested that ROS involved in rTcdB induced apoptosis and autophagy. DPI and Anti.A successfully inhibited the antitumor immune effect induced by rTcdB. As ICD is determined by a variety of factors, rTcdB is a potential tool for further exploring the circumstances that trigger ICD, which may offer us a good choice for designing the new chemotherapeutic drugs with immunogenic properties.