The human neuroblastoma cell line IMR32 produces and secretes substantial amounts of TRH-immunoreactivity (TRH-IR) as measured with radioimmunoassay (RIA) using the nonspecific antiserum 4319. It was found that synthesis of TRH-IR is dependent on neural differentiation: under serum-free conditions these cells exhibit neural characteristics as defined by morphological and biochemical standards. After culture for 2–5 days in serum-free medium cells grew large neural processes and expressed neuron-specific markers whereas glial-specific markers were absent. TRH-IR became detectable after 4–8 days serum-free conditions. Northern blot and chromatographic analysis, however, failed to detect proTRH mRNA and authentic TRH in these cells. Moreover, TRH-IR was undetectable in the RIA using TRH-specific antiserum 8880. TRH-IR produced by differentiated cells was retained on a QAE Sephadex A-25 anion-exchange column and thus negatively charged. HPLC analysis showed coelution with the synthetic peptide pGlu-Glu-ProNH2. Study of the mechanisms regulating production of this novel peptide in these cells should further elucidate the role differentation plays in the synthesis of neuropeptides.

Additional Metadata
Keywords cell line, differentiation, IMR32 pyroglutamyl-glutamyl-prolineamide, neuroblastoma, neuron, TRH
Persistent URL dx.doi.org/10.1016/0006-8993(94)91346-3, hdl.handle.net/1765/61149
Journal Brain Research
Citation
Rondeel, J.M.M, Klootwijk, W, Linkels, E, de Greef, W.J, & Visser, T.J. (1994). Neural differentiation of the human neuroblastoma cell line IMR32 induces production of a thyrotropin-releasing hormone-like peptide. Brain Research, 665(2), 262–268. doi:10.1016/0006-8993(94)91346-3