Abstract:

Objective To investigate the effects of Eriocalyxin B (EriB) on immunoglobulin class switch recombination (CSR). Methods B lymphocytes (1B4.B6) were treated with lipopolysaccharide (LPS) and different doses (0 μmol/L, 0.75 μmol/L, 1.5 μmol/L and 2.0 μmol/L) of EriB, the proliferation of these cells was analyzed by MTT and flow cytometry, the generation of immunoglobulin, efficiency of CSR and expression of relevant genes which play important roles in CSR were examined by ELISA, RT-PCR and Western blotting respectively, and the regulation of NF-κB transcription via EriB was determined by luciferase assay. Results With the increase of EriB concentration, the proliferation and CSR of B cells were defective. EriB inhibited the activation of NF-κB1 through blocking IκBα phosphorylation and degradation. It also directly repressed the transcription level of NF-κB1. Conclusion EriB could inhibit CSR through repressing the activation of NF-κB signaling pathway.

Key words: Eriocalyxin B, immunoglobulin class switch recombination, NF-κB signaling pathway