Effect of poly(L-lactide) surface topography on the morphology of in vitro cultured human articular chondrocytes

Human articular chondrocytes were cultured in vitro on poly(L-lactic) acid, PLLA, substrates. Influence of the surface topography on cell morphology was found. Different surface microtopographies were obtained on PLLA by crystallizing at 120 degrees C after nucleation treatments that include isothermal stages at temperatures just below (55 degrees C) and just above (75 degrees C) the glass transition temperature (T-g = 65 degrees C). Isothermal crystallization from the melt gave rise to big spherulites (approx. 50 mu m diameter) with approx. 1 mu m depth. Crystallization after nucleation treatments results in smaller (approx. 5 mu m)-difficult to distinguish-spherulites. Cell viability was excellent and not affected by the surface roughness. Cell population on the nucleated samples resembles the result of culture on the reference tissue culture polystyrene (TCPS). However, cells cultured on big spherulites (PLLA isothermally crystallized without nucleation treatment) show a peculiar morphology, with a more isolated disposition and growth oriented in a characteristic direction.