New approach to investigate Common Variable Immunodeficiency Disorder using Spectrochemical analysis of blood

ATR-FTIR spectroscopy was used for the analysis of blood serum and blood plasma to investigate samples from patients with common variable immune deficiency. The uploaded files contain raw data (classed) and pre-processed data from the recruited cohort of patients and healthy controls. For each study subject, blood spots of both serum and plasma were produced in duplicate; 10 spectra were collected per 50 µL dried blood spot (total of 20 spectra per biofluid).

The spectra files were pre-processed using the IRootLab toolbox (trevisanj.github.io/irootlab/), within MATLAB R2017a software (MathWorks). Initially, the 20 replica spectra per sample were averaged in order to work with a sample-based classification. Two pre-processing techniques were independently tested: 1) rubber-band baseline correction followed by vector normalisation and 2) by Savitzky-Golay (SG) smoothing (second-order polynomial and nine filter coefficients). Once the spectra had been pre-processed, two regions of interest were extracted from the spectra; the Fingerprint region, which covers the area between wavenumbers 1800-900 cm^-1; and the High region, which covers wavenumbers 3700-2800 cm^-1.