Table 1. OC-STAMP mRNA induction by RANKL.

BMC and RAW 264.7 cells were cultured with or without RANKL. At the days indicated, RNA was collected and assessed by high-density microarray (Affymetrix Gene Chip) and by real-time RT-PCR. Results are shown in Relative Units. Real-time PCR results were normalized to GAPDH. Both methods found very low baseline levels and strong up-regulation of OC-STAMP by RANKL in both BMC and RAW cells.

Microarray
Days	2		4
	BMC	RAW	BMC	RAW
− RANKL	20.7	29.3	56	46.1
+ RANKL	3076.3	239.5	2859.3	336.9

Real-Time RT-PCR
− RANKL	0.007	0.064	0.089	0.079
+ RANKL	125.9	23.1	65.9	25.8