One limitation is time efficiency, as it involves time-consuming steps such as transfection, selection, and virus amplification. These systems typically require longer periods of time to be carried out compared to bacterial systems. Another drawback is that it requires very expensive media, and may be especially costly for small-scale experiments. Additionally, viral infection causes cell lysis in the late stage which leads to the production of immature proteins. Lastly, glycosylation is different from the mammalian system which could result in improper maintenance of epitopes on protein.