[Several methodologic problems in the control of cell cultures]

Area of Science:

• Cell biology
• Virology
• Molecular biology

Background:

• Continuous cell lines are crucial for biological research.
• Potential contamination can compromise experimental results.
• Characterizing cell line contaminants is essential for data integrity.

Purpose of the Study:

• To investigate the presence of contaminants in human and animal cell lines.
• To identify viral agents and mycoplasma within cell cultures.
• To assess potential HeLa cell contamination in human cell lines.

Main Methods:

• Karyological analysis
• Electron microscopy
• Virological assays
• Molecular biological techniques
• Electrophoretic motility of glucose-6-phosphate dehydrogenase (G-6-PDG)

Main Results:

• Mycoplasma contamination was found in all tested cell lines.
• Various oncornaviruses (Types A, B, C), and paramyxoviruses were identified.
• High molecular RNA (64-70 S) associated with reverse transcriptase activity confirmed oncornaviruses.
• HeLa cell marker chromosomes, absence of Y chromosomes, and G-6-PDG Type A motility suggested HeLa contamination.

Conclusions:

• Human and animal cell lines frequently harbor viral and mycoplasma contaminants.
• Oncornaviruses were characterized by high molecular RNA and reverse transcriptase activity.
• Specific markers indicate a high likelihood of HeLa cell contamination in the examined human cell lines.