IMR-90

The IMR-90 cell line is a well-characterized human diploid fibroblast strain derived from the normal lung tissue of a 16-week-old female Caucasian fetus, established by W.W. Nichols and colleagues. These adherent cells exhibit typical fibroblast-like morphology and maintain a normal female diploid karyotype (46, XX), providing a physiologically relevant human genetic background that contrasts sharply with the aberrant karyotypes of transformed cancer cell lines.

A defining feature of IMR-90 cells is their finite replicative lifespan. They are capable of achieving approximately 58 population doublings before entering replicative senescence, making them an indispensable in vitro model for studying cellular aging, telomere biology, and senescence-associated pathways. This Hayflick limit enables researchers to investigate the molecular and phenotypic progression from proliferation to senescence in a controlled, human-relevant system.

IMR-90 cells are also highly valued for their viral susceptibility, which is comparable to that of WI-38 and MRC-5 cells. They are susceptible to multiple viruses, including poliovirus, herpes simplex virus, and vaccinia virus, supporting their use in virological studies. Their thoroughly characterized division potential and viral susceptibilities allow them to serve as a standard alternative to WI-38 and other human lung cell strains.

Beyond aging and virology, IMR-90 cells are widely applied in pulmonary fibrosis research, toxicology assays, drug testing, and cytoskeletal dynamics studies. They are amenable to transfection, facilitating genetic and epigenetic investigations. Furthermore, they have been used to generate induced pluripotent stem cells (iPSCs), extending their utility into regenerative medicine.