VERO cells were cultivated in microcarriers (MCs) using a bioreactor w
ith a working capacity of 3.7 l. We studied the effect of MCs concentr
ation in the proportion of MC-bearing cells and on the kinetics of cel
l growth, as well as the cell growth with a batch, fed-batch and perfu
sion mode operation. The data show that, in a batch system, with an in
itial VERO cell inoculum of 3 x 10(4) cells/mg of MCs, 65%, 55% and 50
% of the MCs were shown to be totally covered by cells after 7 days in
cultures with respectively 2, 5 and 10 mg/ml of MCs. It was observed,
that higher concentrations of MCs produced higher final yields of VER
O cells. With 10 mg/ml of MCs, after 7 days of culture, a final yield
of 10(10) cells in the bioreactor, was obtained. The study of cell gro
wth with a batch, fed-batch or perfusion system showed that the medium
renewal allowed the continuous cell growth with the obtention of a fi
nal yield of 4 x 10(9) cells in a culture with 2 mg/ml of MCs. The num
ber of cells that can be easily reached in these culture systems, whic
h can be even further improved, indicates its usefulness for cell prop
agation and the preparation of cell products such as viral antigens.