[Cloning and expression of the gene encoding rat IgE-dependent histamine-releasing factor and effect study on the recombinant protein].
OBJECTIVE
To clone and express the gene encoding rat IgE-dependent histamine-releasing factor (rHRF) and to study the effect of recombinant rHRF to induce histamine release from rat sensitized mast cells.


METHODS
The complete coding region of rHRF was cloned and expressed in BL21 cells. The soluble recombinant rHRF was purified. Aliquots of the mast cells obtained from the lungs of OVA-immunized rats were separately stimulated by recombinant rHRF at different concentration. The released histamine was measured by the OPT spectrofluorometric procedure.


RESULTS
The cloned DNA fragment showed 97% nucleotide sequence identity and 95% deduced amino acid sequence identity with the mRNA of rat IgE-dependent histamine-releasing factor (or translationally controlled tumor protein) in GenBank. The recombinant rHRF showed a relative molecular mass of 24 000 in SDS-PAGE. The purified rHRF which was independent of the allergen induced histamine releasing from the sensitized mast cells in a dose-dependent manner.


CONCLUSIONS
The recombinant rHRF, which showed the effect of inducing histamine release from sensitized mast cells, would play an important role in the allergen diseases.
Chen
Xiao-xiang
XX
Department of Parasitology, Preclinical School of Sun Yat-sen University, Guangzhou 510080, China. chenxiaoxiang75@yahoo.com.cn
Hu
Xu-chu
XC
Xu
Jin
J
Zheng
Nan-cai
NC
Yu
Xin-bing
XB
D000485:Allergens / Q000494:pharmacology; D000818:Animals; D014408:Biomarkers, Tumor / Q000235:genetics / Q000378:metabolism* / Q000494:pharmacology*; D002478:Cells, Cultured; D003001:Cloning, Molecular; D004591:Electrophoresis, Polyacrylamide Gel; D006632:Histamine / Q000378:metabolism; D008297:Male; D008407:Mast Cells / Q000187:drug effects* / Q000378:metabolism; D010047:Ovalbumin / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism* / Q000494:pharmacology*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D000090324:Tumor Protein, Translationally-Controlled 1
D000485:Allergens; D014408:Biomarkers, Tumor; D011994:Recombinant Proteins; D000090324:Tumor Protein, Translationally-Controlled 1; D006632:Histamine; D010047:Ovalbumin