1. Differentiation of rat and human NIP cells toward an endocrine or duct phenotype.
Differentiation of rat and human NIP cells toward an endocrine or duct phenotype. A: The DNA products (upper panels) of the correct predicted sizes generated by RT-PCR of NIP RNA using amplimers to rat (690 bp) or human (1 kb) CK19 and rat NCAM (326 bp). The authenticity of the DNA products was verified by Southern blot hybridization using 32P-labeled CK19 and NCAM, respectively (lower panels). B: Expression of homeodomain protein IDX-1 in human SCs derived from NIP cells. Immunocytochemistry (Cy3 immunofluorescence) in SCs (after treatment with bFGF plus EGF for 17 days, then incubation with Activin-A plus HGF for 2 weeks) using an antiserum to IDX-1. Bright punctate structures are immunopositive nuclei throughout the SCs (inset; original magnification ×400). Preimmune serum control staining of human SCs were negative (not shown). C: RT-PCR of mRNA prepared from SCs. DNA product (553 bp) obtained by RT-PCR (top panel) was confirmed by Southern blot hybridization (bottom panel). D: Western immunoblot of protein extract (positive control) prepared from human SCs derived from NIP cells (left) compared with extract prepared from a rat clonal β-cell line (INS1) (right) using an antiserum to IDX-1 (upper panels) or preimmune serum (lower panels). The exposure was longer for the Western blot prepared for human NIP cells.
Henryk Zulewski et al. Diabetes 2001;50:
©2001 by American Diabetes Association