Antibody repertoire sequencing was performed as previously described (23 (link), 29 (link)). Briefly, plasmablasts were sorted into 96-well plates containing lysis buffer (10mM Tris with 1U/μL RiboLock RNAse inhibitor) and stored at −80C. One of 96 unique well-specific DNA barcodes was added to the cDNA of each cell by template switching during reverse transcription with Maxima Reverse Transcriptase (Thermo Fisher Scientific). Well ID-tagged cDNA was pooled from each plate, and plate-specific indices were added during PCR with primers specific for the HC and LC constant regions. Gamma, Kappa, and Lambda primers were as described in (23 (link)), and the nested Alpha gene-specific primer sequences were 1: ATT CGT GTA GTG CTT CAC GTG; 2: CTA TGC GCC TTG CCA GCC CGC GGG AAG ACC TTG GGG CTG GT. Barcoded amplicons from multiple plates were pooled prior to the addition of sequencing adaptors and final purification with AMPure XP beads (Beckman Coulter). Samples sequenced prior to Fall 2014 underwent Roche 454 sequencing using Lib-L adaptors and Titanium chemistry. Following the development of 600 bp read lengths on the Illumina MiSeq platform, samples underwent 2 × 300 MiSeq analysis.