Effects on growth behavior in continuous hybridoma cell cultures: The roleof viral contamination

This article describes the retrovirus expression with optimal nutrient supp ly and its potential growth inhibition effects in continuous hybridoma cell cultivation. A special reactor setup with total cell retention was develop ed to examine growth inhibition effects. Using this fermentation strategy w e observed a decrease of viability cell rate which occurred at a defined st ate of the process despite sufficient nutrient supply. Therefore we assume that inhibitory substances are responsible for these effects. The molecular weight range of the inhibitory substances and the possible retrovirus coop eration of these growth inhibition effects were examined. To determine the molecular weight range we used the following methods: ultrafiltration, gelf iltration, ultracentrifugation and gel electrophore sis. Furthermore, RT-PC R and western-/immunoblot are used to detect retrovirus particles in the su pernatant and to show a retrovirus participation on growth inhibition effec ts. The possible growth modulation was tested in a biological assay (MTT-as say).