Characters of location in cells and binding activity of chicken Ii and B-L gene ex-pressed products / 中国免疫学杂志

ABSTRACT

Objective:To study characters of the location in cells and binding activity of chicken Ii and B-L gene expressed products.Methods:The cloned gene segments of chicken Ii,B-LA and B-LB were respectively inserted into prokaryotic or eukaryotic expression plasmids,and then these recombinant plasmids were respectively alone transfected or cotransfected into engineering bacteria, Rosetta(DE3) or 293T cells.All of the recombinant bacteria were induced to express and their products then were renatured.The singly expressed products were detected to their immunogenicity with Western blot, and the co-expressed products were tested their binding with pull-down method and ( SDS-) PAGE.Results:First six of prokaryotic and eukaryotic recombinant expression plasmids were con-structed.The eukaryotic expressed products of Ii, B-LA and B-LB genes located in cellular plasma membrane.The single protein molecules were achieved from prokaryotic expressed products, which were renatured and purified with a Ni-column respectively.Secondly the prokaryotic expression Ii,B-LA and B-LB molecules could respectively induce mouse to product specific anti-bodies, which could recognize the corresponding products in eukaryotic expression.This indicated that they retained their antigenicity.Finally with pull-down from the products in co-expression in engineering bacteria and renaturation the Ii/B-LA or Ii/B-LB complexes were purified and the Ii,B-LA or B-LB monomers were dissociated from these complexes after a SDS treatment.Conclusion:The prokaryotic or eukaryotic expressed products of chicken Ii and B-L genes could retain their antigenicity,and chicken Ii could bind B-L molecules after prokaryotic coexpression and renaturation.These results provide a useful method to study the relation between Ii and MHC molecules.