Authenticating Hybrid Cell Lines

Abstract

Hybrid (both intra-species and inter-species) cell lines arise through intentional or nonintentional fusion of somatic cells having different origins. Hybrid cell lines can pose a problem for authentication testing to confirm cell line identity, since the results obtained may not conform to the results expected for the two parental cell types. Thus, depending on the identity testing methodology, a hybrid cell may display characteristics of one of the parental cell type or of both. In some instances, the hybrid cell line may display characteristics that are different from those displayed by either parental cell type; these differences may not necessarily indicate cellular cross-contamination. Testing should be performed as soon as possible after an intended fusion has occurred, so that a baseline reference profile is available for later comparison. In this article, we describe the various approaches that have been used for identifying hybrid cell lines and the results that might be expected when using various technologies for this purpose.

Multiple approaches revealed MGc80‐3 as a somatic hybrid with HeLa cells rather than a gastric cancer cell line

“…In addition to STR profiling analysis, other approaches, including establishing single-cell-derived subclones, karyotyping, phenotype analysis and high-throughput sequencing analysis are used for the authentication of cell lines, especially for that of cell mixtures 9 and hybrid cell lines. 10 During karyotyping, typical marker chromosomes have been identified in special cell lines, including M1 to M20 marker chromosomes in HeLa cells, which can be used as indicators of intraspecies cellular contamination in intraspecies. 11,12 The cellular origin of the cell lines can be identified by observing pathological phenotype, including lumen formation or mucus secretion in adenocarcinoma, or cellular keratinization and intercellular conjunctions in squamous cell carcinoma, 13 or using immunohistochemical (IHC) analysis for the expression of certain proteins.…”

“…Therefore, multiple approaches were needed to confirm the properties of MGc80‐3 as a HeLa cell line (total replacement), a cell line of gastric adenocarcinoma contaminated by HeLa cells (a mixture), or a somatic hybrid of HeLa cells and gastric adenocarcinoma. In addition to STR profiling analysis, other approaches, including establishing single‐cell‐derived subclones, karyotyping, phenotype analysis and high‐throughput sequencing analysis are used for the authentication of cell lines, especially for that of cell mixtures 9 and hybrid cell lines 10 . During karyotyping, typical marker chromosomes have been identified in special cell lines, including M1 to M20 marker chromosomes in HeLa cells, which can be used as indicators of intraspecies cellular contamination in intraspecies 11,12 .…”