Article Figures & Data
Figures
- Fig 1
Graph representing the signal (in response units) relative to the PNHS spiked with 0.0025 to 100 μg/ml of human anti-ESA antibody 8C10G4. A total of 13 curves were analyzed in duplicate. The graph was constructed using a 4-parameter logistic nonlinear regression model in GraphPad Prism v. 5.0. The response unit per concentration is reported with the standard error of the mean (SEM).
- Fig 2
Graphical representation of the measurement of 0, 15, 50, and 200 ng/ml of human antibody 8C10G4 in the presence of 5 μg/ml of anti-ESA antibodies IgG1, IgG2, and IgM as well as a cocktail containing 5 μg/ml each of IgG1, IgG2, and IgM.
- Fig 3
Pooled normal human serum samples containing 250 ng/ml of human anti-ESA antibody 8C10G4 spiked with 0 to 100 μg/ml of epoetin alfa. The response unit readout is displayed on the y axis, and the concentration of epoetin alfa (in μg/ml) is displayed on a logarithmic scale on the x axis. The solid line indicates the ACP (243.75).
- Fig 4
Graphical representation of a Wilcoxon two-sample test, showing the distribution of the anti-ESA IgG4 concentration (in ng/ml) displayed on the y axis and the patient classification of amPRCA and non-PRCA patients on the x axis.
Tables
- Table 1
Results from the SPRIA and ImmunoCAP 100 anti-ESA IgG4 assays and a cell-based assay for neutralizing antibodiesa
Sample SPRIA ImmunoCAP 100 Patient classification based on NAb assay Result Isotype(s) Anti-ESA Ab (ng/ml) Result Anti-ESA IgG4 Ab (ng/ml) 1 Positive IgG1, IgG2, IgG3, IgG4 >10,000 Positive 145 amPRCA 2 Negative Negative Non-PRCA 3 Positive IgG1, IgG2, IgG4 6,030 Positive 89 amPRCA 4 Positive IgG1, IgG2, IgG4 620 Positive 89 amPRCA 5 Positive IgG1, IgG2, IgG3, IgG4 >10,000 Positive 669 amPRCA 6 Negative Negative Non-PRCA 7 Positive IgG1 600 Negative Non-PRCA 8 Positive IgG1 (IgG4b) 1,730 Positive 95 amPRCA 9 Negative Negative Non-PRCA 10 Negative Negative Non-PRCA 11 Negative Negative Non-PRCA 12 Negative Negative Non-PRCA 13 Positive Unable to determine 340 Negative Non-PRCA 14 Negative Negative Non-PRCA 15 Negative Negative Non-PRCA 16 Positive Unable to determine 520 Positive 59 amPRCA 17 Positive IgG1 6,860 Negative amPRCA 18 Positive IgG1 840 Positive 18 Non-PRCA 19 Positive IgG1 3,690 Negative Non-PRCA 20 Positive IgM 920 Negative Non-PRCA 21 Positive IgG1 1,210 Negative Non-PRCA 22 Positive IgM 1.94 Negative Non-PRCA 23 Positive IgG3 700 Negative Non-PRCA 24 Positive IgG1 0.93 Negative Non-PRCA 25 Positive IgG1, IgG2, IgG3, IgG4 >10,000 Positive 4,978 amPRCA ↵a All patient samples that had an anti-ESA concentration of greater than 250 ng/ml by SPRIA were further characterized for isotype (IgG1, IgG2, IgG3, IgG4, and IgM) and tested in a cell-based bioassay to determine if neutralizing antibodies were present. All patient samples were tested in the ImmunoCAP anti-ESA IgG4 assay. All samples that that had less than 15 ng/ml of anti-ESA IgG4 were reported as negative.
↵b This patient tested anti-ESA IgG4 antibody positive at a subsequent time point.
