library_construction_protocol: Spike-specific memory B cells (bound to Spike-PE tetramer) were sorted from the PBMCs of healthy controls (n=3), anti-TNF treated IBD patients (n=5) and anti-IL-12/23 treated IBD patients (n=4). Post dose 2 (Timepoint 4) and post dose 3 (Timepoint 6) samples were sorted and sequenced in two batches, by Timepoint. Single cells were encapsulated in Gel-Beads-in emulsions (GEMs) using a 10X Genomics Chromium X with the Chromium GEM-X Single Cell 5' Kit v3. CITE-seq gene expression libraries (Single Cell 5' R2-only v3, 10X Genomics) and BCR V(D)J libraries (Single Cell V(D)J R2-only v3, 10X Genomics) were prepared as recommended by the 10X Genomics user guides.