Antibiotics have been a routinely used component in cell cultures to prevent the growth of bacteria but several researchers doing primary cell culture have showed their interest in avoiding them for several reasons in order to save their cultures and help the cells grow happy! Researchers unanimously agree on the saying, “With good lab practice, antibiotics are not necessary”. Let us look into why antibiotics are among the less preferred cell culture components even though they efficiently prevent bacterial contamination in cultures.
Cell culture is one of the most complex domain in the biological sciences and provides an excellent model for investigating the bio-physiological processes and therapeutic response at cellular and sub-cellular levels.Cell culture medium is optimized for maintaining healthy proliferating cells to enhance research efficacy of the experiments and assays performed by researchers. But in this game, a fundamental hindrance is the occurrence of microbiological contamination (mostly bacterial contamination). Therefore, standard cell culture protocols emphasize on including the use of antibiotics like streptomycin, gentamycin etc. as media supplements to reduce the chances of contamination. However, a prevalent question keeps on bothering the research community: Are antibiotics really helpful or do they create unnecessary complications in the culture practice?
Antibiotics are not the good Samaritans in animal cell culture. These chemicals affect the metabolism of the cultured cells and affect proliferation, differentiation and gene expression of the cells, thus hampering experiment results and questioning the validity of the same. Antibiotics harm non-bacterial structures in the cells and hinders the proliferation rate of cells. Cell proliferation has been shown to improve in several cases, in the absence of antibiotics. From the 1970s to the 90s, several reports showed anti-proliferative effects of beta-lactam antibiotics (Neftel et al., 1987) and aminoglycosides (Fischer et al., 1975, Cooper at al., 1990, Cooper et al., 1991) on eukaryotic cell cultures but it is not always obvious for researchers and thus get overlooked.
If you find the cells in culture not growing properly or at the usual proliferative rate, always keep a point of troubleshooting related to the use of antibiotics if there are no signs of contamination in the dish or flask. The possibility of a restricted metabolism due to the use of antibiotics is a fair one. In a study, Llobet and colleagues described how antibiotics mix can affect the differentiation of human adipose-tissue derived stem cells into adipocytes and similar hindrances were reported in embryonic stem cells (Varghese et al., 2017), mesenchymal stem cells (Chang et al., 2006), primary cancer cell lines (Relier et al., 2016) and keratinocytes (Nygaard et al., 2015). Moreover, as mentioned beforehand, the use of antibiotics can significantly alter gene expression and cell signaling regulation (Ryu et al., 2017), leading to altered drug response results and deregulated cell cycle regulation.
Keeping the cell culture medium free from microorganism contamination can be well accomplished by having proper aseptic knowledge and following food lab practices, even if antibiotics are avoided for the better. For more tips on efficient primary cell culture, consult one of the leading primary cell organization Kosheeka at info@kosheeka.com
