CD22 and acute lymphoblastic leukemia: Furthermore, given the fact that the expression of CD surface markers like CD22, CD45, and HLA-DR is generally interrelated with the lineage and differentiation stage of immune hematopoietic cells [80–83], together with the observed significant variation of ADAM6 and/or PRSS1 levels within CD22+/CD22−, CD45+/CD45−, and HLA-DR+/HLA-DR− ALL patients, these findings shed light on the possible interplay between ADAM6 and/or PRSS1 with the differentiation process of immune hematopoietic cells.