Automated production of monoclonal antibodies in a cytostat.

Suspension cultures of B cell hybridomas can be maintained in exponential growth, by matching their rate of replication with the input of medium. A cytostat has been designed to perform this operation automatically. The conditions of cytostatic growth were tested on a panel of 10 hybridomas, representing a range of growth rates, specificities, affinities, quantities and types of globulins produced. No special media were needed, but it was necessary to shield the cells from light and stir them at rates lower than 60 rpm. The rate of multiplication is, on average, 15% slower than in stationary cultures, but the cells reach almost twice the concentration. The yield of immunoglobulin is a direct function of the number of live cells and does not depend on their rate growth. All cell lines grew well in serum-free medium and produced the equivalent of 50 standard tissue culture bottles each day, for period of several weeks.