1  PvSeroApp in R Tutorial

1.1 Data Analysis: runPvSeroPipeline()

Run this global function runPvSeroPipeline() embedded within the {SeroTrackR} R package! This function contains all of the steps in order of how to perform the Plasmodium vivax serology test and treat protocol as found in our application!

1.1.1 Visualisation of the PvSeroApp Pipeline

1.1.2 Using Tutorial Dataset: Load the Data

We will be using the build-in files in the R package for this tutorial, as shown below.

library(SeroTrackR)
library(tidyverse)

your_raw_data <- c(
  system.file("extdata", "example_MAGPIX_plate1.csv", package = "SeroTrackR"),
  system.file("extdata", "example_MAGPIX_plate2.csv", package = "SeroTrackR"), 
  system.file("extdata", "example_MAGPIX_plate3.csv", package = "SeroTrackR")
)
your_plate_layout <- system.file("extdata", "example_platelayout_1.xlsx", package = "SeroTrackR")

To run your OWN data, follow the code below and uncomment (i.e., remove the hashtags):

your_raw_data <- c(
  "PATH/TO/YOUR/FILE/plate1.csv",
  "PATH/TO/YOUR/FILE/plate2.csv",
  "PATH/TO/YOUR/FILE/plate3.csv"
)
your_plate_layout <- "PATH/TO/YOUR/FILE/plate_layout.xlsx"

1.1.3 Run Classification: Yes

final_analysis <- runPvSeroPipeline(
  raw_data = your_raw_data, 
  plate_layout = your_plate_layout, 
  platform = "magpix", 
  location = "ETH", 
  experiment_name = "experiment1", 
  std_point = 10,
  classify = "Yes", 
  algorithm_type = "antibody_model", 
  sens_spec = "balanced"
)
#> PASS: File example_magpix_plate1.csv successfully validated.
#> PASS: File example_magpix_plate2.csv successfully validated.
#> PASS: File example_magpix_plate3.csv successfully validated.
#> Plate layouts correctly identified!
#> QC Processes completed.
#> MFI to RAU conversion completed.
#> Please write a standard point curve.
#> QC Plotting completed.
#> Pv classification completed.

1.1.3.1 Classification

This is a table containing the classification results (seropositive or seronegative) for each SampleID. In this case, the classification results are stored in the pred_class_max column as we chose the sens_spec = "balanced". If you change it to another type of threshold, then the suffix of that column will change accordingly.

You will also see the relative antibody unit (RAU) values (columns with antigen names), whether the sample passed QC check (QC_total) and the plate that they were run on.

final_analysis[[1]] %>%
  head() %>% 
  kable()
SampleID Plate QC_total PvEBP Pv-fam-a PvMSP5 PvMSP1-19 PvMSP8 PvPTEX150 PvCSS PvRBP2b pred_class_max
ABC013 plate1 pass 0.0003339 0.0015045 0.0002163 0.0014567 0.0000195 0.0001591 0.0000772 0.0003714 seropositive
ABC097 plate2 pass 0.0004324 0.0015615 0.0001944 0.0013373 0.0000195 0.0001549 0.0000705 0.0009189 seropositive
ABC181 plate3 pass 0.0003822 0.0015832 0.0002144 0.0013711 0.0000195 0.0001582 0.0000710 0.0002070 seropositive
ABC022 plate1 pass 0.0200000 0.0200000 0.0007373 0.0194885 0.0006247 0.0003145 0.0006008 0.0004895 seropositive
ABC106 plate2 pass 0.0057123 0.0193731 0.0007458 0.0195240 0.0006263 0.0003077 0.0006480 0.0126203 seropositive
ABC190 plate3 pass 0.0098260 0.0200000 0.0007400 0.0200000 0.0006020 0.0003171 0.0006555 0.0175253 seropositive

1.1.3.2 Standard Curve Plot

The standard curve plots are generated from the antibody data from the standards you indicated in your plate layout (e.g. S1-S10) and Median Fluorescent Intensity (MFI) units are displayed in log10-scale. In the case of the PvSeroTaT multi-antigen panel, the antigens will be displayed and in general your standard curves should look relatively linear (only when the y-axis is on logarithmic scale).

final_analysis[[2]]
#> NULL

1.1.3.3 Bead Counts QC Plot

A summary of the bead counts for each plate well are displayed, with blue indicating there are sufficient beads (≥15) or red when there are not enough. If any of the wells are red, they should be double-checked manually and re-run on a new plate if required.

The function will inform you whether there are “No repeats necessary” or provide a list of samples to be re-run. In the example data, the beads in plate 2 wells A1 and A2 will need to be repeated

final_analysis[[3]] # Plot

final_analysis[[4]] # Samples to repeat 
#> # A tibble: 2 × 4
#>   Location SampleID Plate  QC   
#>   <chr>    <chr>    <chr>  <chr>
#> 1 A1       Blank1   plate2 fail 
#> 2 A2       Blank2   plate2 fail

1.1.3.4 Blanks QC Plot

The Median Fluorescent Intensity (MFI) units for each antigen is displayed for your blank samples. In general, each blank sample should have ≤50 MFI for each antigen, if they are higher they should be cross-checked manually.

In the example data, blank samples recorded higher MFI values for LF005 on plate 1 and should be checked to confirm this is expected from the assay.

final_analysis[[5]]

1.1.3.5 Model Output Plot

The automated data processing in this app allows you to convert your Median Fluorescent Intensity (MFI) data into Relative Antibody Units (RAU) by fitting a 5-parameter logistic function to the standard curve on a per-antigen level. The results from this log-log conversion should look relatively linear for each antigen.

final_analysis[[6]]
#> $`1`
#> Ignoring unknown labels:
#> • fill : "Antigen"

1.1.4 Run Classification: No

no_classification_final_analysis <- runPvSeroPipeline(
  raw_data = your_raw_data, 
  plate_layout = your_plate_layout, 
  platform = "magpix", 
  location = "ETH", 
  experiment_name = "experiment1", 
  std_point = 10,
  classify = "No", # key if you do NOT want any classification performed i.e., you do not have PvSeroTaT antigens 
  algorithm_type = "antibody_model", 
  sens_spec = "balanced"
)
#> PASS: File example_magpix_plate1.csv successfully validated.
#> PASS: File example_magpix_plate2.csv successfully validated.
#> PASS: File example_magpix_plate3.csv successfully validated.
#> Plate layouts correctly identified!
#> QC Processes completed.
#> MFI to RAU conversion completed.
#> Please write a standard point curve.
#> QC Plotting completed.
#> No Classification Performed.

1.1.4.1 MFI and RAU Data

no_classification_final_analysis[[1]]  %>%
  head() %>% 
  kable()
SampleID Plate QC_total PvEBP_MFI PvEBP_Dilution Pv-fam-a_MFI Pv-fam-a_Dilution PvMSP5_MFI PvMSP5_Dilution PvMSP1-19_MFI PvMSP1-19_Dilution PvMSP8_MFI PvMSP8_Dilution PvPTEX150_MFI PvPTEX150_Dilution PvCSS_MFI PvCSS_Dilution PvRBP2b_MFI PvRBP2b_Dilution
ABC013 plate1 pass 2712 0.0003339 1569.0 0.0015045 673 0.0002163 327 0.0014567 182.0 1.95e-05 936.0 0.0001591 223 0.0000772 1068.0 0.0003714
ABC014 plate1 pass 134 0.0000216 378.0 0.0004204 117 0.0000277 197 0.0010331 58.0 1.95e-05 122.0 0.0000225 93 0.0000298 465.5 0.0001536
ABC015 plate1 pass 182 0.0000232 209.0 0.0002466 208 0.0000616 374 0.0015985 221.5 1.95e-05 293.0 0.0000535 868 0.0002235 463.0 0.0001527
ABC016 plate1 pass 152 0.0000222 229.5 0.0002688 101 0.0000244 89 0.0005994 48.0 1.95e-05 109.0 0.0000220 110 0.0000383 591.0 0.0001989
ABC017 plate1 pass 1135 0.0001478 236.0 0.0002758 299 0.0000950 507 0.0019840 209.5 1.95e-05 1665.5 0.0002668 266 0.0000893 671.0 0.0002277
ABC018 plate1 pass 174 0.0000229 395.0 0.0004370 175 0.0000460 78 0.0005452 70.0 1.95e-05 294.5 0.0000537 92 0.0000296 103.0 0.0000238

1.1.4.2 QC Plots

Repeat the same steps as above to find the QC plots!

#### Standard Curve Plot
no_classification_final_analysis[[2]]
#> NULL

#### Bead Counts QC Plot
no_classification_final_analysis[[3]] # Plot

no_classification_final_analysis[[4]] # Samples to repeat 
#> # A tibble: 2 × 4
#>   Location SampleID Plate  QC   
#>   <chr>    <chr>    <chr>  <chr>
#> 1 A1       Blank1   plate2 fail 
#> 2 A2       Blank2   plate2 fail

#### Blanks QC Plot
no_classification_final_analysis[[5]]


#### Model Output Plot
no_classification_final_analysis[[6]]
#> $`1`
#> Ignoring unknown labels:
#> • fill : "Antigen"

1.1.5 Create a PDF Report

renderQCReport(
  your_raw_data, 
  your_plate_layout, 
  "magpix", 
  location = "ETH",
  path = "results/" # defaults to your current working directory
)