EFFECT OF AGE ON THE DIFFERENTIATION OF PORCINE ADIPOSE STROMAL-VASCULAR CELLS IN CULTURE

Stromal-vascular (S-V) cells isolated from adipose tissue of newborn p igs (NBPC) and mature pigs (MPC) by collagenase digestion were used to evaluate differences in preadipocyte culture and development. Cells w ere seeded at a density of 3 x 10(4) cells/cm(2) on six-well (35-mm) t issue culture plates in 3 mL of DMEM/HAM's F12 medium plus 10% fetal c alf serum: and cultured at 37 degrees C under a humidified atmosphere of 95% air:5% CO2 for 24 h. Cells were then washed thoroughly in DMEM/ HAM's F12 medium without fetal calf serum and maintained in serum free (SF) medium or SF medium supplemented with 2.5% newborn pig serum (NB PS) or mature pig serum (MPS) for 12 d. After 1 d, more NBPC adhered t o the culture plates, as indicated by DNA values. After 12 d, protein per culture well was not significantly different, but DNA concentratio n per well remained higher (P < .05) in cultures of NBPC indicating fe wer MPC. Protein:DNA ratios were higher (P < .05) in cultures of MPC r egardless of the medium, reflecting larger cell size. More cells conta ining fat deposits were seen with NBPC in all conditions in comparison with MPC, and more fat was deposited in NBPC in SF than in SF plus NB PS or MPS. The NBPC had higher (P < .05) sn-glycerol-3-phosphate dehyd rogenase (GPDH; EC 1.1.1.8) per protein than MPC regardless of the med ium. For bath cell types, GPDH activity in either serum was less than activity of cells grown in SF. This study demonstrated that adipose S- V cells from NBPC attach to the plate more efficiently, maintain a sma ller cell size, and exhibit more differentiation when using morphologi cal criteria and GPDH activity/milligram of protein. The results also indicated that the intrinsic activity of the S-V cells, rather than se rum-borne factors, are responsible for successful adipose tissue cultu re and development.