Overview
ISO/TR 4752:2025 - Biotechnology: Inventory of methods for detection of microbiological contamination in mammalian cell culture is a Technical Report (first edition, June 2025) that compiles and describes available approaches to detect microbiological contamination in mammalian cell cultures. The document provides an inventory of methods for detecting common contaminants - bacteria, fungi, viruses and mycoplasma - and gives practical considerations for selecting appropriate tests. It is expressly not applicable to prions or protists.
Key topics and technical requirements
- Scope and purpose: Presents an overview of methods rather than prescriptive, normative test requirements; intended to support risk-based testing strategies for cell culture testing and contamination monitoring.
- Detection process & general concepts: Covers principles of aseptic testing, limitations of visual inspection, and the need for risk assessment based on cell origin, reagents and intended use.
- Terms and definitions: Defines key terms used in testing workflows (e.g., accuracy, sample, sensitivity, PCR assay, dPCR, NGS, rRNA, mycoplasma).
- Contamination test information: Guidance on assessing likely contaminants using exposure history, raw materials (e.g., animal sera), and cell type.
- Critical control points: Identifies areas to control to ensure reliable detection - samples, reagents and equipment, operation, personnel and environment - supporting robust quality control and documentation.
- Annexes with exemplary methods:
- Annex A: bacteria and fungi testing methods
- Annex B: virus detection approaches
- Annex C: mycoplasma detection techniques
These annexes summarize available methods and pro/con considerations without prescribing a single technique.
- Quality and documentation: Emphasizes validation, controls, data recording and the limits of testing (cannot guarantee absolute absence of all contaminants).
Practical applications
- Use this standard to develop or refine a contamination-testing regime for mammalian cell cultures used in:
- basic and translational biomedical research
- biobanking and cell repositories
- preclinical and manufacturing cell-based workflows
- Practical uses include selection of test methods (culture-based, molecular assays such as qPCR/dPCR, sequencing-based approaches), design of environmental monitoring, and establishing SOPs for routine cell culture testing and documentation.
Who will use ISO/TR 4752:2025
- Biomedical researchers, laboratory managers and technicians
- Biobank operators and custodians of cell lines
- Quality assurance personnel in academic, clinical and industrial cell-culture facilities
Related standards
Relevant ISO references cited in the report include standards for terminology and methods such as ISO 11139, ISO 20395, ISO 20397 (NGS/MPS), and environmental guidance like ISO 16000‑44 and ISO 11057.
Keywords: ISO/TR 4752:2025, microbiological contamination, mammalian cell culture, mycoplasma detection, virus detection, bacteria and fungi testing, cell culture testing, contamination monitoring, PCR, dPCR, NGS.