Fig. 3.

IgA1 and IgG1 clonal profiles are unique for each donor. Correlation between patient–antibody repertoires for IgA1 (left) and IgG1 (right) for each time point as indicated by the color-coded squares (T1: brown, T2: green & T3: blue). These correlation plots are based on concentrations of all clones detected, counting the overlap in clones having identical retention time and mass in the LC-MS Fab traces. The degree of correlation is shown in a color scale from white to red, where a value of zero indicates no correlation, and a value of 1 indicates the samples are identical. The IgA1 repertoires reveal close to zero correlation between samples of different patients, but between time points within one patient generally a high correlation is observed. The IgG1 repertoires show a similar trend as IgA1, with some notable exceptions indicated by the blue boxes. This unexpected overlap in repertoires originates from high concentrations of a single IgG1 these patients have in common, which we show later to be tocilizumab. Disregarding the tocilizumab IgG1, the data reveal that both IgA1 and IgG1 clonal profiles are explicitly unique for each donor. P24 was included although no IgA data were obtained for T3. At the top, H01 and H02 show data obtained from the plasma samples originating from two healthy donors, whose blood was sampled longitudinally at 0, 1, and 2 months, here included as controls.