Quaternized vinyl‐ and alkynyl‐pyridine reagents were shown to react in an ultrafast and selective manner with several cysteine‐tagged proteins at near‐stoichiometric quantities. We have demonstrated that this method can effectively create a homogenous antibody–drug conjugate that features a precise drug‐to‐antibody ratio of 2, which was stable in human plasma and retained its specificity towards Her2+ cells. Finally, the developed warhead introduces a +1 charge to the overall net charge of the protein, which enabled us to show that the electrophoretic mobility of the protein may be tuned through the simple attachment of a quaternized vinyl pyridinium reagent at the cysteine residues. We anticipate the generalized use of quaternized vinyl‐ and alkynyl‐pyridine reagents not only for bioconjugation, but also as warheads for covalent inhibition and as tools to profile cysteine reactivity.
A general strategy for the synthesis of diversely substituted 3,4,5‐trihydroxypiperidines (including two natural products), 5‐amino‐3,4‐dihydroxypiperidines, 3,4,5‐trihydroxypipecolic acids, and 2‐(aminomethyl)‐3,4,5‐trihydroxypiperidines is reported. The procedure used a double reductive amination or a Strecker reaction, starting from differently protected aldehydes readily synthesized on a gram scale from D‐mannose. The biological activities of the target compounds were evaluated, and some of them showed moderate inhibition of α‐L‐fucosidase and β‐glucosidase.
The ability of dendritic cells to coordinate innate and adaptive immune responses makes them essential targets for vaccination strategies. Presentation of specific antigens by dendritic cells is required for the activation of the immune system against many pathogens and tumors, and nanoscale materials can be functionalized for active targeting of dendritic cells. In this work, we integrated an immunogenic, carbohydrate melanoma-associated antigen-mimetic GM3-lactone molecule into mannosylated peptide amphiphile nanofibers to target dendritic cells through DC-SIGN receptor. Based on morphological and functional analyses, when dendritic cells were treated with peptide nanofiber carriers, they showed significant increase in antigen internalization and a corresponding increase in the surface expression of the activation and maturation markers CD86, CD83 and HLA-DR, in addition to exhibiting a general morphology consistent with dendritic cell maturation. These results indicate that mannosylated peptide amphiphile nanofiber carriers are promising candidates to target dendritic cells for antigen delivery.
Quaternized vinyl‐ and alkynyl‐pyridine reagents were shown to react in an ultrafast and selective manner with several cysteine‐tagged proteins at near‐stoichiometric quantities. We have demonstrated that this method can effectively create a homogenous antibody–drug conjugate that features a precise drug‐to‐antibody ratio of 2, which was stable in human plasma and retained its specificity towards Her2+ cells. Finally, the developed warhead introduces a +1 charge to the overall net charge of the protein, which enabled us to show that the electrophoretic mobility of the protein may be tuned through the simple attachment of a quaternized vinyl pyridinium reagent at the cysteine residues. We anticipate the generalized use of quaternized vinyl‐ and alkynyl‐pyridine reagents not only for bioconjugation, but also as warheads for covalent inhibition and as tools to profile cysteine reactivity.
Glycan structures are common posttranslational modifications of proteins, which serve multiple important structural roles (for instance in protein folding), but also are crucial participants in cell–cell communications and in the regulation of immune responses. Through the interaction with glycan‐binding receptors, glycans are able to affect the activation status of antigen‐presenting cells, leading either to induction of pro‐inflammatory responses or to suppression of immunity and instigation of immune tolerance. This unique feature of glycans has attracted the interest and spurred collaborations of glyco‐chemists and glyco‐immunologists to develop glycan‐based tools as potential therapeutic approaches in the fight against diseases such as cancer and autoimmune conditions. In this review, we highlight emerging advances in this field, and in particular, we discuss on how glycan‐modified conjugates or glycoengineered cells can be employed as targeting devices to direct tumor antigens to lectin receptors on antigen‐presenting cells, like dendritic cells. In addition, we address how glycan‐based nanoparticles can act as delivery platforms to enhance immune responses. Finally, we discuss some of the latest developments in glycan‐based therapies, including chimeric antigen receptor (CAR)‐T cells to achieve targeting of tumor‐associated glycan‐specific epitopes, as well as the use of glycan moieties to suppress ongoing immune responses, especially in the context of autoimmunity.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.