SPN and diffuse large B-cell lymphoma: Although human CD5+CD43+ B cells have not been clearly characterized and whether these cells are equivalent to B‐1a cells in mice is unclear, some studies support the hypothesis that a subset of B cells possessing the characteristics of B‐1a cells of mice exists in humans.48, 49, 50, 51 These B‐1a‐like cells may be the origin of the CD5+CD43+ cells in DLBCL, which warrants further investigation.