Functional and morphological characteristics of bovine adrenal chromaffin cells on macroporous...

Adrenal chromaffin cells (ACCs) secrete several neuroactive substances that are effective in influencing pain sensitivity in the central nervous system as well as enhancing the recovery of the intrinsic nigrostriatal dopaminergic system in patients with Parkinson's disease. ACC transplantation may be upregulated by the use of three-dimensional (3-D) scaffolds. In this study, we determined whether biodegradable poly(D,L-lactic-coglycolic acid) (PLGA) (85:15) sponges could be used as support for chromaffin cells. ACCs were isolated from bovine adrenal glands by standard perfusion (95% purity) followed by additional purification (>99.5% purity). ACC (approximately 5 x 10(5) cells) suspension in collagen (type I) was seeded on prewetted sponges and cultured in DMEM-F12 (1:1) medium (5% fetal bovine serum). The catecholamine and enkephalin levels of the samples were measured by high-performance liquid chromatography and radioimmunoassay. Cell morphology was examined by transmission electron microscopy. Morphological evidence showed prolonged viability of chromaffin cells on scaffolds having pores of 250-400 microm. Cell counts and scanning electron microscopy demonstrated that the majority of seeded cells were located within the scaffold. Chromaffin cells exhibited higher levels of enkephalins and catecholamines on PLGA scaffold compared with their monolayer cultures. By the use of 3-D PLGA as support for ACCs, it is possible to upregulate metabolic function and localize a high number of morphologically healthy-looking cells. Highly purified ACCs cultured on PLGA scaffold may have promise in transplantation studies, because these cells are less immunogenic and may be applied to in vivo settings by using short-term immunosuppression.