Figure 2

PTHrP was markedly up-regulated during immortalization of PBMCs with HTLV-1 infection. (A) PTHrP mRNA expression during immortalization of PBMCs with HTLV-1. Total RNA was extracted from the co-cultures at various time points and PTHrP mRNA expression was measured by real-time RT-PCR using the Taqman method. PTHrP expression was normalized to human β₂M and the data were represented as fold change over uninfected PBMCs from day 0. After using Dunnett's method to adjust for multiple comparisons, the PBMC+HTLV-1 group was shown to have higher PTHrP mRNA level than the PBMC group (p < 0.0001). The PMBC+HTLV-1+IL-2 group was not different from the PBMC group due to the very limited data available for the PBMC group. These limited data were caused by low cell viability resulting in low RNA recovery from the PBMC group. (B) PTHrP protein expression during immortalization of PBMCs with HTLV-1. Secreted PTHrP was measured in the conditioned medium from the co-culture assays by IRMA. Results showed marked up-regulation of PTHrP secretion in PBMCs infected with HTLV-1 during the immortalization phase. PTHrP concentrations were significantly different over time between treatment groups (p < 0.0001). While PTHrP secretion increased in HTLV-1-treated groups over time, PTHrP secretion in the other 4 groups remained negligible and unchanged. After using Dunnett's method to adjust for multiple comparisons, both HTLV-1-treated groups had significantly higher protein levels than the PBMC group (p < 0.0001).