Cellular antigens in nephroblastoma: identification with monoclonal antibodies which recognize hemopoietic cells

The correlation between expression of differentiation antigens and morphogenesis was examined in 11 human nephroblastomas using monoclonal antibodies which recognize both hemopoietic and renal cells. Analysis of frozen tissue sections by indirect immunofluorescence revealed that blastema cells and some tubules were recognized by BA-1 and OKB2, which identify unstimulated B cells and granulocytes. Stroma, some tubules, and focal blastema were recognized by BA-2, which identifies a 24-kDa antigen on leukemic cells and platelets. Mature epithelium in glomerular bodies was identified by C3bR and J5, which recognize CR1 and the common acute lymphoblastic leukemia antigen, respectively. Tissue sections from a clear cell sarcoma and a mesoblastic nephroma were notably reactive only with BA-2. These observations demonstrate that the relationship between antigen expression and morphology in nephroblastomas is similar to that observed in fetal kidney and suggest that expression of these cell surface antigens may have a role in morphogenesis.