Expression of NK cell-specific mRNAs in the CD34⁺ EB cell–derived and ES cell–derived LAK cells. RT-PCR analysis was performed with total RNAs extracted from the C57BL/6 mouse spleen-LAK cells, type I LAK (LAKa, LAKj, LAK34a-1, and LAK34a-3) cells, type II LAK (LAK34a-2) cells, ES-pre-B cells, EB34-pre-B cells, P815 cells, 32Dcl3 cells, and OP9 cells, and analyzed on 1.2% agarose gels. The first lane is for size standard, and the rightmost lane is a negative control for cDNA. Results of the 2× 20-cycle amplification with different set of primers for NKR-P1A (top), NKR-P1B, granzyme A (gzm A), granzyme B (gzm B), perforin, and β-actin (bottom) genes are shown.