FCS files for patient samples analysed in IgA2⁺ B cells and IgA2 anti-dsDNA antibodies are selectively targeted by belimumab after rituximab therapy in systemic lupus erythematosus (McCluskey et al)

SUMMARY

No theragnostic biomarkers are available for systemic lupus erythematosus (SLE) to enable a precision medicine approach. Serum IgA2 anti-dsDNA antibody levels are associated with response to combination belimumab after rituximab therapy in SLE (BEAT-lupus, ISRCTN 47873003). Testing samples from the CALIBRATE trial (NCT02260934) we confirmed that baseline IgA2 anti-dsDNA antibody levels are strongly associated with response to belimumab after rituximab, and reduced together with IgA2 B cells only after this combination treatment. Increased serum BAFF levels are associated with a subsequent rise in IgA2 anti-dsDNA antibody levels after rituximab therapy. IgA2 plasmablasts have increased BAFF receptor and IL-10 expression compared to IgA1 plasmablasts, and a distinct integrin profile implicating a gut mucosal origin. These findings validate IgA2 anti-dsDNA antibodies as a theragnostic biomarker of response and provide mechanistic insight into the selective targeting of IgA2+ B cells by combination belimumab after rituximab in SLE.

The files in this repository consist of the FCS files (each file is the flow cytometry data of one patient) as well as the metadata for each sample in an excel spreadsheet.