Background:

The technique for inducing pearl production in mollusks, which relies on the grafting of a round nucleus and a piece of mantle tissue from a donor within the gonad of a recipient, generates high mortality and rejection rates.

Goals:

To develop methodological basis for in vitro primary cultivation of mantle cells in the pearl oyster Pinctada mazatlanica, with potential application to pearl production.

Methods:

Five methods for enzymatic dissociation, three different culture media, two cell substrates, and four osmolarities of the culture medium were evaluated. In vitro intake of calcium by mantle tissue was also quantified through histochemistry ad atomic absorption spectrophotometry.

Results:

The addition of collagenase I (414 U/ mg), at 37°C increased viability and performance of disaggregated cells, which grew better in RPMI-1640 cell medium with poly-D-lysine. Under these conditions, the cells changed from the round-type cell to the fibroblast-type cell at third day and were maintained until day 25. Culture of explants resulted better with RPMI-1640 medium, at 37 °C, without poly-D-lysine, and at 0.6 M NaCl, where calcium absorption was evident.

Conclusions:

These results set the basis of future investigations reformulating new culturing media, evaluating growth factors, and identifying molecules and genes related to biomineralization and synthesis of CaCO3, calcite and aragonite.