Simple and reliable conditions for routine, long-term culturing of fetal human pancreatic tissue fragments.

Fetal human pancreatic tissue fragments were isolated and cultured for 18 wk. Insulin production was almost continuous during this period. Multiplication of cells was observed at the second week, and these cells later aggregated as epithelioid cells and formed pseudoislets. The growth characteristics, insulin-like immunoreactivity, and endocrine properties of these cells were evidenced by light microscopy, immunocytochemistry, electron microscopic examination, and measurement of the total insulin content. These results indicate that long-term culture of fetal islets may be useful in clinical work and provides a possible method for increasing islet mass and reducing immunogenicity.