Novel human interferon alpha 2b (hIFNα2b) muteins were developed by substituting cysteine residue (C) at positions 2 and 99 with aspartic acid residues (D). The mutein forms were then studied for pharmacokinetic prof...Novel human interferon alpha 2b (hIFNα2b) muteins were developed by substituting cysteine residue (C) at positions 2 and 99 with aspartic acid residues (D). The mutein forms were then studied for pharmacokinetic profile. In addition, the influence of charge on the protein structure was tested in vivo for the biodistribution pattern. Codon substitutions were performed by Polymerase Chain Reaction (PCR)-based site-directed mutagenesis on a previously constructed synthetic hIFNα2b open reading frame (ORF) cloned in pET32b expression plasmid. The result of nucleotide sequencing analysis confirmed that all codons were replaced successfully without any additional mutation. Three mutant forms of hIFNα2b ORF were overexpressed in Escherichia coli BL21 (DE3) resulted in three muteins: hIFNα2b C2D, hIFNα2b C99D, hIFNα2b C2D C99D. To follow the kinetic and localization of the mutein interferon after intravenous administration, Tc99m was used to label the proteins. In particular of elimination half-life, it was shown that hIFNα2b C2D C99D > hIFNα2bC2D > hIFNα2bC99D > wild type. hIFNα2b C2D C99D mutein showed highest blood accumulation after 30 minutes administration. Taken together, the charge of hIFNα2b seems to be responsible for the fate of hIFNα2b in vivo.展开更多
文摘Novel human interferon alpha 2b (hIFNα2b) muteins were developed by substituting cysteine residue (C) at positions 2 and 99 with aspartic acid residues (D). The mutein forms were then studied for pharmacokinetic profile. In addition, the influence of charge on the protein structure was tested in vivo for the biodistribution pattern. Codon substitutions were performed by Polymerase Chain Reaction (PCR)-based site-directed mutagenesis on a previously constructed synthetic hIFNα2b open reading frame (ORF) cloned in pET32b expression plasmid. The result of nucleotide sequencing analysis confirmed that all codons were replaced successfully without any additional mutation. Three mutant forms of hIFNα2b ORF were overexpressed in Escherichia coli BL21 (DE3) resulted in three muteins: hIFNα2b C2D, hIFNα2b C99D, hIFNα2b C2D C99D. To follow the kinetic and localization of the mutein interferon after intravenous administration, Tc99m was used to label the proteins. In particular of elimination half-life, it was shown that hIFNα2b C2D C99D > hIFNα2bC2D > hIFNα2bC99D > wild type. hIFNα2b C2D C99D mutein showed highest blood accumulation after 30 minutes administration. Taken together, the charge of hIFNα2b seems to be responsible for the fate of hIFNα2b in vivo.
文摘SHP2 (Src homology 2 domain-containing protein tyrosine phosphatase-2)是由Ptpn11基因编码的非受体型蛋白酪氨酸磷酸酶,通过RAS (rat sarcoma)-ERK (extracellular regulated protein kinases)信号通路的活化调控细胞生长、分化和凋亡,并参与PD-1 (programmed cell death protein 1)/PD-L1(programmed cell death ligand 1)通路的免疫监控,已成为有突破意义的抗癌药物新靶标.靶向SHP2变构位点的抑制剂通过稳定SHP2非活性构象而抑制磷酸酶催化功能,具有很好的成药性.但是,SHP2功能获得性突变(gainoffunction,简称GOF)导致一系列发育障碍疾病和肿瘤的发生,并对SHP2野生型变构抑制剂产生耐药性.本工作首次以靶向SHP2激活突变体的变构抑制剂为靶头,基于PROTACs(proteolysis-targeting chimeras)技术,设计合成了一系列全新SHP2小分子降解剂.其中先导化合物3f和4d保持了对突变型SHP2^(E76A)的酶抑制活性,而且对于野生型SHP2依赖的人食管鳞癌细胞KYSE-520和突变型SHP2^(N58S)人大细胞肺癌细胞NCI-H661都显示强效抗增殖活性,比相应变构抑制剂的活性提高了5~10倍,为治疗SHP2突变或活化导致的遗传性疾病或肿瘤提供了新的干预策略.
