text: Titration of Ab-01 inhibition of ex vivo response to rhIL21
  Samples from 4 individual healthy human donors were pre-incubated for 2 hours at the indicated concentration of Ab-01 or the control IgG1TM prior to addition of 10 ng/mL rhIL21 and 2 hr incubation, and the effect on the 6 biomarkers was then assessed (Figures 4 and 5). For the first 2 donors tested, even the lowest concentration of Ab-01 (0.1 mug/mL, 0.66 nM) resulted in complete inhibition of the rhIL21 response, therefore the two subsequent donors were tested at increasing concentrations of Ab-01 starting at 0.003 mug/mL. Ab-01 inhibited the response of all 6 genes in all 4 donors. IC50 values ranged between 0.003 and 0.015 mug/mL Ab-01(Figure 5). Control IgG1TM had no significant effect on rhIL21 response (Figure4B).
  Figure 4
  Average percent inhibition of the expression level of 6 IL21-responsive genes. Percent inhibition values were calculated based on RQ (relative quantification) values of untreated control and rhIL21-treated samples for each of the 4 donors, and subsequently the mean and standard deviation were determined for each gene shown. A: Percent inhibition in presence of Ab-01. B: Percent inhibition in presence of control IgG1TM. Data for the 0.1 mug/mL , 0.3 mug/mL and 1 mug/mL concentrations were generated using 4 donors. Data for the higher and the lower concentrations were generated using 2 donors.
  Figure 5
  Inhibition by Ab-01 at the indicated concentration is shown for 6 IL21-responsive genes. IC50 values of inhibition curves shown in Figure 4A were calculated using curve fit (XLfit) program for each of the referred biomarker genes. Values for the 0.1 mug/mL, 0.3 mug/mL and 1 mug/mL concentrations were generated using 4 donors. Data for the higher and the lower concentrations were generated using 2 donors each.
  