Abstract
The therapeutic efficacy of antibodies can be successfully improved through targeted delivery of potent cytotoxic drugs in the form of antibody-drug conjugates. However, conventional conjugation strategies lead to heterogeneous conjugates with undefined stoichiometry and sites, even with considerable batch-to-batch variability. In this study, we have developed a chemo-enzymatic strategy by equipping the C-terminus of anti-CD20 ofatumumab with a click handle using Sortase A, followed by ligation of the payload based on a strain-promoted azide-alkyne cycloaddition to produce homogeneous conjugates. The resulting antibody-drug conjugates fully retained their antigen binding capability and proved to be internalized and trafficked to the lysosome, which released the payload with a favorable efficacy in vitro and in vivo. Thus, this reported method is a versatile tool with maximum flexibility for development of antibody-drug conjugates and protein modification.
Highlights
Antibody-drug conjugates (ADCs) selectively deliver potent toxic payloads to antigen-positive tumor cells via specific antibody binding to reduce off-target toxicity and widen the therapeutic window in comparison to chemotherapeutics or combination therapy
Recent successes in the development of ADCs for targeted cancer therapy, such as Brentuximab vedotin (Adcetris®, SGN-35, Seattle Genetics, Inc., Bothell, WA, USA) and Trastuzumab emtansine
All approved ADCs are produced by chemical conjugation that covalently attaches the toxic payload to the antibody through surface-exposed lysine or cysteine residues generated by reducing intrachain disulfide bonds of the antibody, which leads to heterogeneous mixtures in terms of position and stoichiometry of the payload coupled to the antibody
Summary
Antibody-drug conjugates (ADCs) selectively deliver potent toxic payloads to antigen-positive tumor cells via specific antibody binding to reduce off-target toxicity and widen the therapeutic window in comparison to chemotherapeutics or combination therapy. All approved ADCs are produced by chemical conjugation that covalently attaches the toxic payload to the antibody through surface-exposed lysine or cysteine residues generated by reducing intrachain disulfide bonds of the antibody, which leads to heterogeneous mixtures in terms of position and stoichiometry of the payload coupled to the antibody (defined as “drug to antibody ratio”, DAR). Diverse site-specific conjugation technologies have been further developed to produce homogeneous ADCs. One option is engineering free cysteines into antibodies which can react with maleimide-functionalized. 2017, 18, 2284 homogeneous ADCs. One option is engineering free cysteines into antibodies which can react with maleimide-functionalized toxins, thereby yielding homogeneous ADCs with an improved ttohxeinrasp, tehuetricebwyinyideoldwin[g6]h. CChheemmiiccaall ssttrruuccttuurreess ooff tthhee ddiiffffeerreenntt ssuubbssttrraatteess ffoorr tthhee eennzzyymmaattiicc aanndd cchheemmoo--eennzzyymmaattiicc aapppprrooaacchh.. ((11)) GGGGGG--PPEEGG--NN33 ((GGPPNN)) iiss aa bbiiffuunnccttiioonnaall ssmmaallll mmoolleeccuullee ccoommpprriissiinngg aann oolliiggooggllyycciinnee aatt tthhee N-terminus and a bio-orthogonal azide functional group at the C-terminus through an oligoethylene glycol ligation; (2) DBCO-PEG-vc-PAB-MMAE was monomethyl auristatin E (MMAE) derivative containing aadidbiebneznyzlycylccylocloocotyctnyen(eDB(DCBOC),Oa)n, oalnigooelitghoyelethnyelgelnyecogll(yPcEoGl )(,PaEpGro),teaaspe-rsoetneasisteiv-seevnasliitniveevciatrliunleli-nceitr(uvlcl)indeip(evpct)iddeiapnedptaidseelfa-nimdmaolsaetilvf-eimspmaocelart,ipv-eamspinaocebre,nzpy-alcmaribnaombeantezy(PlcAarBb)a; m(3a) tGe G(GPA-vBc)-; (P3A) BG-GMGM-vAcE-PAwBas-MmModAifEiewdabsymthoediafidedditbioynthoef anddoiltiigoongolyfcaineotliogtohgelyvcci-nPeAtoB-tMheMvAc-EP.AB-MMAE
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
