The growth and harvest of large quantities of animal cells is a prerequisite to making commercially available many of the laboratory advances of biotechnology, including some viral vaccines and therapeutically important proteins. A variety of methods for growing animal cells are now in use in laboratories, but they are difficult to adapt to the large scale required for pharmaceutical manufacturing. Scientists at KC Biological in Lenexa, Kans.
, now propose a ceramic matrix as the support for animal cell growth. In the January BIO/TECHNOLOGY, Bjorn K. Lydersen and colleagues describe experiments using ceramic cylinders containing channels 1 millimeter square passing in parallel through their length. These vessels provide, in a relatively small volume, a large amount of surface area. To create an automated cell-growing system, Lydersen and colleagues encapsulated a ceramic matrix in an open-ended glass cartridge connected at both ends to an apparatus that circulates gas-permeated, nutrient medium through the matrix. The system monitors acidity and disollved oxygen and automatically adjusts the mixture of gases provided. Eight out of 10 cell types testes– derived from human, monkey, hamster, chicken, trout and mosquito–grew to greater density in the ceramic chamber than in conventional containers.
In more recent experiments, the sciensts used a ceramic of a slightly different composition and with a rougher surface to immobilize other cells, which do not naturally adhere to surfaces. This method has increased the yield of antibody from the hybridoma cells used to produce monoclonal antibodies. So far, the largest ceramics that have been used for cell culture have more than 18 square meters of surface area and can produce more than 10.
sup.11 cells. Lydersen and colleagues say,” .
.. no practical limits to further increases in scale have been encountered, and therefore significantly larger systems utilizing the ceramic are being developed.”