Core constructs and their uses in configuring pharmaceutical molecules
The present disclosure provides various core constructs. According to embodiments of the present disclosure, the core construct can be used to configure pharmaceutical molecules. In particular, the core construct may be conjugated with a functional element via the click chemistry.
1. A core construct, comprising a center core, and a plurality of first elements, wherein,
the center core comprises (1) a plurality of lysine (K) residues, wherein each K residue and its next K residue are separated by a filler sequence comprising glycine (G) and serine (S) residues, and the number of K residues ranges from 2 to 15, or (2) the sequence of (X aa -K) n , where X aa is a PEGylated amino acid having 2 to 12 repeats of ethylene glycol (EG) unit, and n is an integer from 2 to 15;
one of the amino acid residue at the N- or C-terminus of the center core is a cysteine residue or has an azide or alkyne group, wherein when the amino acid residue at the N- or C-terminus of the center core is the cysteine residue, the core construct further comprises a coupling arm, wherein one terminus of the coupling arm is linked with the thiol group of the cysteine residue, and the other terminus of the coupling arm has an azide, alkyne, tetrazine, trans-cyclooctene (TCO), or strained alkyne group;
each of the plurality of first element has an N-Hydroxysuccinimide (NHS) group or a dansyl group; and
the plurality of first elements are respectively linked to the K residues of the center core via direct linkage between each of the first elements and each of the K residues.
2. The core construct of claim 1 , wherein the coupling arm is a PEG chain having 2-12 repeats of EG units.
3. The core construct of claim 1 , wherein the amino acid residue having the azide group is L-azidohomoalanine (AHA), 4-azido-L-phenylalanine, 4-azido-D-phenylalanine, 3-azido-L-alanine, 3-azido-D-alanine, 4-azido-L-homoalanine, 4-azido-D-homoalanine, 5-azido-L-ornithine, 5-azido-d-ornithine, 6-azido-L-lysine, or 6-azido-D-lysine.
4. The core construct of claim 1 , wherein the amino acid residue having the alkyne group is L-homopropargylglycine (L-HPG), D-homopropargylglycine (D-HPG), or beta-homopropargylglycine (β-HPG).
5. The core construct of claim 1 , wherein the strained alkyne group is dibenzocyclooctyne (DBCO), difluorinated cyclooctyne(DIFO), bicyclononyne (BCN), or dibenzocyclooctyne (DICO).
6. The core construct of claim 1 , wherein the tetrazine group is 1,2,3,4-tetrazine, 1,2,3,5-tetrazine or 1,2,4,5-tetrazine, or derivatives thereof.
7. The core construct of claim 1 , further comprising a second element that is,
linked to the azide group via copper catalyzed azide-alkyne cycloaddition (CuAAC) reaction or strained-promoted azide-alkyne click chemistry (SPAAC) reaction;
linked to the alkyne group via CuAAC reaction;
linked to the strained alkyne group via SPAAC reaction; or
linked to the tetrazine group via inverse electron demand Diels-Alder (iEDDA) reaction.
8. The core construct of claim 7 , wherein one of the amino acid residue at the N- or C-terminus of the center core is an amino acid having an azide or alkyne group, the other terminus of the center core is a cysteine residue, and the other terminus of the coupling arm has a tetrazine, TCO or strained alkyne group.
9. The core construct of claim 7 , wherein,
the first element is a first single-chain variable fragment (scFv) specific for a cytokine or a receptor of the cytokine; or a soluble receptor of the cytokine; and
the second element is a second scFv specific for a tissue-associated extracellular matrix protein.
10. The core construct of claim 9 , wherein the tissue-associated extracellular matrix protein is selected from the group consisting of α-aggrecan, collagen I, collagen II, collagen III, collagen V, collagen VII, collagen IX, and collagen XI.
11. The core construct of claim 9 , wherein
the cytokine is selected from the group consisting of tumor necrosis factor-α(TNF-α), interleukin-17 (IL-17), IL-1, IL-6, shared protein of IL-12 and IL-23, and B cell activating factor (BAFF);
the receptor of the cytokine is a receptor specific for IL-6 (IL-6R) or a receptor specific for IL-17 (IL-17R); and
the soluble receptor of the cytokine is specific for TNF-α or IL-1.
12. The core construct of claim 7 , wherein,
the first element is a first scFv specific for a first cell surface antigen; and
the second element is a second scFv specific for a second cell surface antigen.
13. The core construct of claim 12 , wherein the first cell surface antigen is selected from the group consisting of, CD5, CD19, CD20, CD22, CD23, CD27, CD30, CD33, CD34, CD37, CD38, CD43, CD72a, CD78, CD79a, CD79b, CD86, CD134, CD137, CD138, and CD319.
14. The core construct of claim 12 , wherein the second cell surface antigen is CD3 or CD16a.
15. The core construct of claim 7 , wherein,
the first element is a peptide hormone, a growth factor, or a first scFv specific for a tumor-associated antigen; and
the second element is a second scFv specific for a cell surface antigen.
16. The core construct of claim 15 , wherein
the peptide hormone is secretin, cholecystokinin (CCK), somatostatin, or thyroid-stimulating hormone (TSH);
the growth factor is selected from the group consisting of epidermal growth factor (EGF), mutant EGF, epiregulin, heparin-binding epidermal growth factor (HB-EGF), vascular endothelial growth factor A (VEGF-A), basic fibroblast growth factor (bFGF), and hepatocyte growth factor (HGF); and
the tumor-associated antigen is selected from the group consisting of human epidermal growth factor receptor 1 (HER1), HER2, HER3, HER4, carbohydrate antigen 19-9 (CA 19-9), carbohydrate antigen 125 (CA 125), carcinoembryonic antigen (CEA), mucin 1 (MUC 1), ganglioside GD2, melanoma-associated antigen, prostate-specific membrane antigen (PSMA), prostate stem cell antigen (PSCA), mesothelin, mucine-related Tn, Sialyl Tn, Globo H, stage-specific embryonic antigen-4 (SSEA-4), and epithelial cell adhesion molecule (EpCAM).
17. The core construct of claim 15 , wherein the cell surface antigen is CD3 or CD16a.
18. The core construct of claim 7 , wherein,
the first element is a first scFv specific for ligand of receptor activator of nuclear factor κB (RANKL); and
the second element is a second scFv specific for collagen I or osteonectin.
19. The core construct of claim 7 , wherein,
the first element is an scFv specific for VEGF-A; and
the second element is a long PEG chain having a molecular weight of about 20,000 to 50,000 daltons.