Article Figures & Data
Figures
- FIG 1
Box plots by serotype and laboratory (I to XII) for ratios of IgG antibody concentrations (micrograms per milliliter) determined by MIA or EIA to the assigned IgG concentrations by WHO. The hinges and the horizontal line of the box represent the 25th and 75th percentiles and the median, respectively, and the red asterisks signify means. The size of the box, coupled with the whiskers, is a direct indicator of the within-laboratory variability of the bias corresponding to the MIA/EIA ratios. The circles correspond to outlying assay values. The positioning of the boxes around the dotted, ideal line with a coefficient of 1 for a given serotype across all laboratories is an indicator of the between-laboratory variability. Results from laboratories I to IX were determined by MIA and results from laboratories X, XI, and XII by the WHO EIA. The number of samples analyzed per serotype was 13.
- FIG 2
Linear regression analysis panels for each serotype, with a different line for each laboratory (I to IX). In total, 13 samples with assigned concentrations were tested: 12 sera from WHO panel B and sample 007sp. Each dot represents the mean of results of 2 or 3 measurements of each sample. The color code of each laboratory is indicated. The line of identity is marked in black. Corresponding data representing outcomes of the linear regression analysis (slope/confidence intervals) can be found in Table S2. Laboratory II did not submit data for serotype 3 and 19A, and laboratories I to II and VIII did not submit data for serotype 6A. All values are in micrograms per milliliter (log transformed).
Tables
- TABLE 1
Comparison of IgG concentrations determined by MIA between different laboratories and the assigned IgG antibody concentrations and serotype-specific comparison of IgG concentrations determined by MIA in different laboratories to the assigned IgG antibody concentrationsa
↵a Ca, accuracy; r, precision; rc, concordance correlation coefficient; NA, not available; [IgG], IgG concentration. Values in parenthesis are 95% confidence intervals. Assigned values are the WHO-assigned IgG concentrations for 12 pneumococcal calibration sera as determined with the pneumococcal standard 007sp (17).
- TABLE 2
Deming regression and Pearson correlation per serotype for quantitation of anti-PPS antibodies in 13 sera from WHO panel B determined using MIA beads coated with polysaccharides obtained from ATCC or SSI Diagnosticaa
↵a LCI, lower confidence interval value; UCI, upper confidence interval value.
- TABLE 3
Slope and Pearson correlation coefficient values for calculated and WHO-assigned values using MIA with ATCC polysaccharides or SSI Diagnostica polysaccharides
FIG S1
Within-laboratory variability (CV%) of MIA by PPS serotype. n = 13 to 15 depending on laboratory and serotype. Download FIG S1, TIF file, 0.1 MB.
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TABLE S1
Overview of MIA protocols used by participating laboratories. ADHS, antibody-depleted human serum; ATCC, American Type Culture Collection; CWPS, cell wall polysaccharide; DMTMM, 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methyl-morpholinium chloride; EDC, 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide; FBS, fetal bovine serum; NBBS, newborn bovine serum; NIBSC, National Institute for Biological Standards and Control; ON, overnight; PBS, phosphate-buffered saline; PLL, poly-l-lysine; PPS, pneumococcal polysaccharide; RPE, phycoerythrin; RT, room temperature; SSI, Statens Serum Institut; Sulpho-NHS, sulpho-n-hydroxysuccinimide; w/o, without. Download Table S1, DOCX file, 0.05 MB.
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TABLE S2
Support for Fig. 2. Data represent linear regression slopes (with 95% confidence intervals) per serotype for each laboratory. Download Table S2, DOCX file, 0.1 MB.
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TEXT S1
Batch numbers of ATCC and SSI Diagnostica polysaccharides used for comparative analysis shown in Fig. S2 and S3. Download Text S1, DOCX file, 0.01 MB.
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FIG S2
Linear regression analysis of results of comparisons between calculated and assigned antipneumococcus (anti-Pn) concentration from WHO panel B, using polysaccharides from ATCC (left panel) or SSI Diagnostica (right panel). The blue line shows linear regression, and the gray area surrounding the blue line represents the 95% CI for the linear regression. Red dotted lines indicate 95% CI for the predicted model of the linear regression. All values represent micrograms per milliliter (log transformed). Download FIG S2, TIF file, 1.9 MB.
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FIG S3
Reproducibility data obtained for ATCC and SSI Diagnostica polysaccharides. All values represent micrograms per milliliter (log transformed). Download FIG S3, TIF file, 1.8 MB.
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FIG S4
(A) Average outcomes for serotype 4 per conjugation method for each sample in calibration serum panel B and 007sp. Whiskers represent ± standard deviations (SD). (B) Deming regression analysis (slope = 0.57; 95% confidence interval, 0.34 to 0.81). All values represent micrograms per milliliter (log transformed). Download FIG S4, TIF file, 0.2 MB.
Copyright © 2019 Meek et al.
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