Some reports have shown that rituximab administration leads to late‐onset neutropenia after ABO‐IRT.31, 61, 62, 63 A previous report showed that late‐onset neutropenia after rituximab administration in ABO‐IRT recipients was related to the increase in serum B‐cell activating factor.32 Our recent reports showed that late‐onset neutropenia was related to acute cellular rejection in ABO‐IRT recipients undergoing rituximab administration.61, 62 Late‐onset neutropenia after rituximab administration might therefore be associated with B‐cell‐related cytokine. This evidence concerns the gene TNFSF13B and neutropenia.