Increased Autoreactivity and Maturity in EBI2+ Antibody-Secreting Cells from Nasal Polyps. Increased Autoreactivity and Maturity in EBI2+ Antibody-Secreting Cells from Nasal Polyps

Rationale: Elevated numbers of antibody secreting cells (ASCs) and anti-dsDNA antibodies are found in nasal polyp (NP) tissue. Tissue anti-dsDNA IgG prospectively predicts recurrent NP, but the characteristics of the source ASCs are unknown. Objectives: To investigate whether NP B cells expressing the extrafollicular marker EBI2 have increased propensity for autoantibody production and to evaluate the molecular characteristics of NP ASCs. Findings: NPs (n=8) showed increased frequencies of anti-dsDNA IgG and total IgG ASCs (34- and 9-fold, respectively, both p2-fold) of specific isotypes (IGHE, IGHA1, IGHA2, and IGHG4), and mature plasma genes including SDC1 and XBP1 than tonsils. GO biological processes indicated upregulated NF-κB and downregulated apoptosis pathways in NP ASCs. Conclusions: NP EBI2+ ASCs secreted increased total and anti-dsDNA IgG compared to those from tonsils and had molecular features of mature plasma cell differentiation. Overall design: Nasal polyp (NP) and control tonsil tissues were obtained from 5 CRSwNP patients and 5 tonsilllar patients accordingly during surgery.