Objective To clone human chemokine ELC and express the ELC fusion protein. Methods Total RNA from human inflammatory tonsil was extracted and the cDNA was generated with reverse transcription. Mature ELC gene was amplified with PCR and NcoⅠand EcoRⅠ sites were added to the 5′ and 3′ terminal respectively, and then cloned into pET32a(+). E.coli DH5? was transformed with the recombinant plasmid, and positive clones were selected. The inserted DNA was verified by enzyme digestion and DNA sequencing. The fusion expression vector of mature ELC was formed with deletion mutation. ELC expression was analyzed by SDS-PAGE and Western blotting and the ELC fusion protein was purified. Results Human chemokine ELC was successfully cloned and the fusion protein was expressed and purified. Conclusion The ELC fusion protein was expressed with solubility.

Objective To study the effects of recombinant chimeric toxin Dsg3EC_(1-2)PE40 on T and B cells from PV patients. Methods The recombinant protein Dsg3EC_(1-2)PE40 was expressed on BL21TrxB (DE3) cells, then identified and purified. ELISPOT assay was used to detect and quantitate autoantibody-producing B cells in different concentrations of recombinant chimeric toxin, and MTT assay and ~3H-TdR assay to observe the metabolism and proliferation of T cells from PV patients in vitro. Results The purity of expressed protein Dsg3EC_(1-2)PE40 was up to 80%. The number of anti-Dsg3 antibody-producing B cells in PBMC from PV patients decreased by 40% with treatment of Dsg3EC_(1-2)PE40, which was significantly lower (P