UcallM® BCR-seq Kit

UcallM® BCR-seq Kit is a library construction kit dedicated to B cell receptor (BCR) immune repertoire sequencing. Combined with high-throughput sequencing and data analysis, it can accurately capture the full-length sequence of BCR complementarity-determining region 3 (CDR3) (covering heavy chain IgH and light chain Igκ/Igλ), comprehensively resolve B cell clonal diversity, somatic hypermutation (SHM) patterns, clonal evolution dynamics and other information, helping to dissect the in-depth mechanism of humoral immune responses.

Experimental Workflow

Application Scenarios 1.Tumor immunity / microenvironment research: track clonal expansion and antibody secretory function of tumor-infiltrating B cells, evaluate immune therapeutic response 2.Exploration of autoimmune disease mechanisms: identify pathogenic autoreactive B cell clones 3.Infectious immunity and vaccine development: track dynamic changes of neutralizing antibodies and accelerate therapeutic antibody screening

Application Case J Clin Invest: Intranasal Prime-Boost Vaccination Drives IM-Primed IgG+ B Cells to Undergo Class Switch to Mucosal IgA and Enhance Protection against SARS-CoV-2 (DOI:10.1172/JCI175233) This study demonstrated that intranasal (IN) boost after intramuscular (IM) vaccination can promote direct conversion of IM-induced IgG+ B cells into IgA+ B cells, which generates potent mucosal immune protection in the upper respiratory tract and effectively blocks SARS-CoV-2 infection.

Figure 1-59. The key finding using BCR-seq in this study confirmed that IgA+ B cells generated after IM+IN sequential immunization were directly derived from IM-primed IgG+ B cells rather than the canonical IgM-IgA pathway. It showed that 90.92% of IgA sequences were highly homologous to IgG sequences, providing molecular evidence for direct class switching from IgG to IgA.