Cell lines are vital tools in biomedical research, used for studying diseases, testing drugs, and developing therapies. From primary to genetically engineered lines, they offer insights at the cellular and genetic levels. Proper establishment and characterization ensure reliability, while challenges like contamination and genetic drift must be addressed. With applications in cancer research, regenerative medicine, and bioproduct manufacturing, cell lines continue to accelerate scientific progress. Kosheeka provides well-characterized cell lines to support accurate and impactful research.