ABSTRACT
Objective:To analysis the Mimotopes of the peptide mimics to PGN using online softwares.Methods: Mimotopes of PGN were screened from 12-mers linear phage display peptide library by using anti-PGN McAb and the antigenicity of selected clones was identified by ELISA.The B cell epitopes,T cell epitopes of ′GRWxHxVxWAGL′ were estimated by DNAstar and online softwares.Results: 16 phage clones that bound with anti-PGN McAb were screened from 12-mers linear phage display peptide library.Among these positive clones,phage clones No.39 shared the conserved sequence:WxHx……AGL found in previous clone No.31(ATWxHxLxSAGL),which provoked an effective protective immunity against infection with S.aureus.To enhance the stability of the conformation as well as adding biotin on the N-ter-minal as a tag,the sequences ′39′ were redesigned and synthesized by adding S(serine)A(alanine) and GG(glycine)on the C-terminal of origin sequence(named SP39).Next,we estimated or predicted antigenic epitopes,T cell epitopes and scores binding to MHC of these peptides by using DNASTAR and online softwares(http://bio.dfci.harvard.edu/Tools/antigenic.pl,www.syfpeithi.de,http://www.darrenflower.info/mhcpred),indicating that SP39 contains sites bound both mice and human MHC.The sequences ′WxHxVxW-′ may be antigenic epitope as SP39,which contains a T cell epitope.Our results showed that both SP39 could bind to both anti-PGN McAb and a polyclonal antibody against S.aureus.Moreover PGN could inhibit the binding of SP39 to the anti-PGN McAb.These data indicated that SP39 mimic to epitopes on PGN.Conclusion: SP39(GRWxHxVxWAGLAGGS) probably display the mimotopes of PGN.
ABSTRACT
Objective:To screen epitope mimics to lipoteichoic acid from a random 12-mer phage display peptide library and i-dentify the specificity of the mimotopes of LTA.Methods:The monoclonal antibody against LTA was used as a target to screen the 12-mer phage display peptide library and the specificity of phage clones were identified by sandwich ELISA.The amino acid sequences of positive phage clones were deduced from DNA sequencing.The specificity of synthetic peptide were identified by sandwich ELISA.Results:4 clones were obtained after 3 rounds of screening.Amino acid sequence analysis revealed four different types of mimotope sequence.A linear peptide (GHxDFRQxxQPS),named L2,which derived from positive sequence was synthesized.ELISA result indicates that L2 can bind to anti-LTA mAb specifically in a dose-dependent manner.Conclusion:The mimotopes of LTA were obtained by using the phage display technology.
ABSTRACT
Objective:To prepare the polyclonal antibodies against advanced oxidation protein products (AOPP),and to provide an effective agent for research on the pathogenesis of AOPP and assess exactly the relationship between AOPP and relative diseases.Methods:AOPP-rabbit serum albumin (AOPP-RSA) was prepared by treating RSA with hypochloric acid.The rabbit anti-AOPP-RSA polyclonal antibodies were generated and purified by affinity chromatography. The titers and the specificity of the antibodies were measured by ELISA.The plasma AOPP and the localization of AOPP in nephridial tissues of some patients with chronic kidney disease (CKD) were determined using rabbit anti-AOPP-RSA.Results:Titers of the antibodies were 10-6.Purified antibodies reacted specifically with oxidized albumin from different genus,but could not react with normal albumin and glycosylated albumin.The high level of AOPP in plasma from CKD patients was confirmed by Western blot.The antibodies could be used to immunostain AOPP deposition in different regions of kidney tissues from both CKD patients and CKD rat models.Conclusion:We successfully generate rabbit anti-AOPP polyclonal antibodies with high titers and striking specificity.The presence of plasma AOPP and localizations of AOPP in kidney tissues of CKD patients can be demonstrated using the antibodies.The development of anti-AOPP polyclonal antibodies may provide a new tool to explore the pathogensis of AOPP and assess exactly the relationship between AOPP and relative diseases.