What are the benefits of using primary cells in cell culture?

There are several benefits of using primary cells in cell culture experiments. One advantage is that primary cells are less reliant on animal experiments and thus make research overall more cost-effective. The fact that they are less reliant on animal models also reduces ethical issues raised regarding doing experiments on animals. Another benefit is that due to the cultivation of primary cells, experiments on humans become possible, which otherwise could not be carried out in vivo. The use of these cells derived from humans generates more accurate and relevant results and thus the in vivo biology of cells can be visualized more closely.