Novel serum replacement based on bovine ocular fluid: a useful tool for cultivation of different animal cells in vitro.

Different mammalian cells in culture have individual nutritional requirements, which are mainly fulfilled by the addition of foetal calf serum (FCS) to the basic medium. Collecting FCS is accompanied with severe animal welfare problems as conscient animals usually are bleeded to death by heart-punctuation without anaesthetics. There exists scientific problems too. Due to the batch-to-batch variability and the relatively high price, different types of serum replacements were introduced. Among them bovine colostrum as a serum substitute for the cultivation of hybridoma cells should be mentioned. The presented experiments were aimed to introduce the simple and effective serum replacement (SR) based on the bovine ocular fluid. Throughout the experiments the bovine ocular fluid alone and in the combination with the sheep's defibrinated plasma and human serum albumin was tested for the growth of different cells growing as a monolayer: (a) Cell lines: WISH (human amniotic cell lines) and VERO. (b) Primary culture: chicken embryonic fibroblasts, human bone-marrow fibroblasts. All growth experiments were performed in parallel with the Foetal Calf Serum (FCS) of three different sources. All types of cells were cultivated in Eagle's medium + antibiotics (Penicillin, Streptomycin, Gentamycin). The most effective was the SR containing approximately 35% of sheep's defibrinated plasma and 1.5% of serum albumin in the bovine ocular fluid. During the experiments 1 and 10% of SR-2.05 or FCS in Eagle's medium were used. After 1, 3 and 6 days of cultivation the cells were counted. The results show that the use of SR-2.05 gives a higher number of cells as compared to most batches of FCS. It is also important that practically no adaptation is needed, meaning that the cells could be grown in Eagle's medium + FCS and in the next passage in Eagle's medium + SR-2.05 and vice versa.