Altered gene expression in lymphoblastoid cell lines after subculture

Lymphoblastoid cell lines (LCLs) are nearly immortalized B lymphocytes that are used as long-lasting supply of human cells for studies on gene expression analyses. However, studies on the stability of the cellular features of LCLs are scarce. To address this issue, we measured gene expression in LCLs with different passage numbers and observed that gene expression substantially changed within 10 passages. In particular, the expression of glyceraldehyde-3-phosphate dehydrogenase (GAPDH), a wellknown housekeeping gene, varied considerably during subculture; thus, the use GAPDH as an internal control may be unsuitable. In conclusion, this study highlights the need for exercising caution during determination of gene expression in LCLs.