Spatial and temporal expression of cell surface molecules during nephrogenesis

Cell-to-cell interaction is fundamental to the development of the kidney. Ureteric bud cells, through cell contact or short-distance interactions, induce the metanephric mesenchyme to convert to epithelia and begin the process of tubulogenesis. To identify new molecules that are involved in these processes, we generated a panel of monoclonal antibodies (MAbs) to the surface of induced mesenchymal cells taken from a day 15 rat embryonic kidney rudiment. MAbs were chosen for further study based either on a distinctive pattern of expression of their antigens or their functional effect on tubulogenesis. We identified a set of MAbs that preferentially stained the glomerular crevice, the first site for formation of the glomerular anlage. Another MAb inhibited tubulogenesis by producing widespread apoptosis in induced mesenchymal cells. This approach promises to identify new molecules that are central to kidney development.