The HEp-2 cell line was established in 1952 by A. E. Moore, L. Sabachewsky, and H. W. Toolan (Cancer Res. 15: 598, 1955) from tumors that had been produced in irradiated-cortisonized weanling rats after injection with epidermoid carcinoma tissue from the larynx of a 56-year-old male (H. Toolan, Cancer Res. 14: 660, 1954). A hardy cell line, HEp-2 resists temperature, nutritional, and environmental changes without a loss of viability. It has supported growth of 10 of 14 arboviruses (Texas Rep. Biol. Med. 15: 588, 1957) and measles virus (Proc. Soc. Exp. Biol. Med. 93: 107, 1956), and it has been used for experimental studies of tumor production in rats, hamsters, mice, embryonated eggs and volunteer terminal cancer patients (Ann. N.Y. Acad. Sci. 76: 497, 1958).

Culture Medium
Leibovitz-15 medium with 10% heat-inactivated fetal bovine serum.

Growth Characteristics
Cells seeded at a concentration of 2x10⁴ cells/cm² in the above culture medium will be 100% confluent in 5 days.

Plating Efficiency
Approximately 44%.

Morphology
Epithelial-like.

Karyology
Chromosome Frequency Distribution 47 Cells: 2n = 46. Occasional polyloids. Several marker chromosomes were observed along with frequent minutes, and often 2 large chromosomes with subterminal centromeres.

Species
Confirmed as human by immunofluorescence and cytotoxic-antibody tests (dye exclusion).

Common Utilization
Supports the growth of a broad range of viruses, including Adenoviruses; Coxsackie B; Herpes simplex Virus; Poliovirus; Respiratory Syncytial Virus; and Vesicular Stomatitis (Indiana Strain) Virus.