Figure 3.

Cell barcodes enable robust antibody repertoire sequencing. Cell barcodes (represented by AAA, CCC and GGG) added with the template switching activity of RT^27,34,43 have many advantages, including preservation of the IgH and IgL pairs expressed by individual B cells, enabling accurate determination of the error-corrected sequence and of clonal proportions. a | In the approach presented, all cDNA generated from each cell receives the same unique barcode; therefore, coexpressed functional genes indicative of functional subsets of B cells (or T cells) can also be characterized.^27,34,43 Both cell and molecular barcodes enable quantitative analysis of mRNA in individual cells. b | Multiple copies of each mRNA are expressed by each cell, and for each cell all mRNA receives the same cell barcode; therefore, cell barcoding enables correction of both PCR and high-throughput sequencing errors. c | Cell barcodes enable accurate determination of clonal proportions. Cell barcodes enable binning of the IgH and IgL chain reads from each B cell, thereby providing accurate determination of clonal proportions. By contrast, molecular barcodes do not enable RT-PCR error correction, IgH and IgL pairing, analysis of coexpressed genes or accurate determination of clonal proportions.