| Size | Price | Stock | Qty |
|---|---|---|---|
| 1mg |
|
||
| 5mg |
|
||
| 10mg |
|
||
| Other Sizes |
| Targets |
Cleavable Linker
CL2A itself has no direct biological target. It serves as a linker in ADCs, providing the structural connection between an antibody and a cytotoxic agent. The drug linker conjugate targets cells expressing the antibody's specific antigen. The cleavable nature of CL2A is designed to exploit the acidic environment of the tumor microenvironment or the lysosomal compartment of target cells, leading to hydrolysis and subsequent release of the payload. The ultimate target of the delivered payload is the DNA topoisomerase I or the microtubule network, depending on the conjugated drug, inducing cell cycle arrest and apoptosis. |
|---|---|
| ln Vitro |
There is no reported direct biological activity for CL2A alone. Its "in vitro activity" is evaluated as part of an ADC. The conjugation efficiency is measured using methods like LC-MS or hydrophobic interaction chromatography (HIC) to determine the drug-to-antibody ratio (DAR). In cell-based assays, the ADC's activity is characterized by its IC₅0 against target antigen-positive cell lines. The bystander effect is confirmed in co-culture assays where only a fraction of cells express the target antigen, yet the ADC shows activity against adjacent antigen-negative cells.
|
| ln Vivo |
No in vivo activity is reported for CL2A as a standalone compound. Its activity is assessed when conjugated to an antibody and payload in animal models of human cancer. In mouse xenograft models, an ADC using the CL2A linker has shown significant anti-tumor activity, leading to tumor regression and improved survival. The pH-sensitive cleavage mechanism is believed to contribute to its efficacy by promoting payload release in the acidic tumor microenvironment, which may also enhance the bystander effect. This has been demonstrated in xenograft models where heterogeneous antigen expression is common.
|
| Enzyme Assay |
A typical non-cellular assay for a pH-sensitive linker like CL2A involves a stability test under different pH conditions. The linker-payload conjugate is incubated in buffers of varying pH (e.g., pH 5.0, 6.0, and 7.4) at 37degC for 24 hours. The release of the payload is monitored by taking samples at various time points and analyzing them by HPLC or LC-MS/MS to calculate the percentage of payload released at each pH. This confirms the faster release under acidic conditions, mimicking the tumor microenvironment or lysosomes, compared to physiological pH (7.4).
|
| Cell Assay |
There is no standard in vitro cell-based assay for the linker alone. For an ADC containing CL2A, an internalization assay is performed using flow cytometry. Cells are incubated with the ADC at 4degC to allow binding, then shifted to 37degC to induce internalization. At different time points, cells are washed to remove surface-bound antibodies, and a secondary antibody is used to detect the remaining surface fraction. Confocal microscopy with lysosomal tracers is used to visualize the colocalization of the ADC in acidic lysosomal compartments, confirming the delivery of the linker-payload to the intended site of cleavage.
|
| Animal Protocol |
Animal studies for CL2A are not performed independently. For an ADC containing this linker, a typical in vivo protocol involves the use of female NSG or BALB/c nude mice bearing established tumor xenografts. Mice are randomized into groups and treated intravenously with the ADC at various doses once weekly for 2-4 weeks. Tumor volumes and body weights are measured biweekly. For a mechanistic study, mice are euthanized at different time points post-dose to collect tumors and blood. The tumor and plasma concentrations of total antibody, ADC, and released payload are quantified by ELISA or LC-MS/MS to confirm tumor-specific delivery and release.
|
| ADME/Pharmacokinetics |
The pharmacokinetic properties are not determined for CL2A itself but for the complete ADC. An ADC featuring the CL2A linker has a typical biphasic profile for the antibody component, with a slow terminal half-life. The linker-payload conjugate is stable in circulation, with minimal deconjugation observed over 7-21 days. The released payload is often rapidly cleared from the plasma, with a short half-life, ensuring minimal systemic exposure. The clearance mechanisms of the ADC involve proteolytic degradation, and the released small molecule is subject to hepatic metabolism and biliary/fecal excretion.
|
| Toxicity/Toxicokinetics |
No standalone toxicity data is available for CL2A. The toxicity of an ADC containing this linker in preclinical studies is attributed to the payload and often includes dose-limiting toxicities such as neutropenia and gastrointestinal effects. In animal models, the MTD is determined through dose-escalation studies. Toxicological monitoring includes CBC with differential, serum chemistry panels, and histopathological examination of major organs (liver, kidney, bone marrow, gastrointestinal tract) to identify target organs of toxicity and to establish a safety margin for the therapeutic dose.
|
| References | |
| Additional Infomation |
CL2A is not a drug and is not approved for human use. It is a research-grade chemical linker specifically designed for the development of cleavable ADCs. Its key attribute is pH-sensitive cleavage, enabling the release of the payload and promoting a bystander effect, which is beneficial for treating tumors with heterogeneous target antigen expression. The labetuzumab govitecan ADC, which uses this linker, is a known construct. No clinical trials are registered for the linker itself. For research use only; not for human therapeutic administration.
|
| Molecular Formula |
C50H79N9O16
|
|---|---|
| Molecular Weight |
1062.21
|
| Exact Mass |
1061.564
|
| CAS # |
2616704-22-2
|
| PubChem CID |
154573757
|
| Appearance |
Colorless to light yellow viscous liquid
|
| LogP |
-3
|
| Hydrogen Bond Donor Count |
6
|
| Hydrogen Bond Acceptor Count |
19
|
| Rotatable Bond Count |
44
|
| Heavy Atom Count |
75
|
| Complexity |
1620
|
| Defined Atom Stereocenter Count |
1
|
| SMILES |
C1CC(CCC1CN2C(=O)C=CC2=O)C(=O)NCC3=CN(N=N3)CCOCCOCCOCCOCCOCCOCCOCCOCCNC(=O)COCC(=O)N[C@@H](CCCCN)C(=O)NC4=CC=C(C=C4)CO
|
| InChi Key |
CJDCJOXHKQMGGB-DBSIFAAZSA-N
|
| InChi Code |
InChI=1S/C50H79N9O16/c51-14-2-1-3-44(50(66)54-42-10-6-40(36-60)7-11-42)55-46(62)38-75-37-45(61)52-15-17-67-19-21-69-23-25-71-27-29-73-31-32-74-30-28-72-26-24-70-22-20-68-18-16-58-35-43(56-57-58)33-53-49(65)41-8-4-39(5-9-41)34-59-47(63)12-13-48(59)64/h6-7,10-13,35,39,41,44,60H,1-5,8-9,14-34,36-38,51H2,(H,52,61)(H,53,65)(H,54,66)(H,55,62)/t39?,41?,44-/m0/s1
|
| Chemical Name |
N-[[1-[2-[2-[2-[2-[2-[2-[2-[2-[2-[[2-[2-[[(2S)-6-amino-1-[4-(hydroxymethyl)anilino]-1-oxohexan-2-yl]amino]-2-oxoethoxy]acetyl]amino]ethoxy]ethoxy]ethoxy]ethoxy]ethoxy]ethoxy]ethoxy]ethoxy]ethyl]triazol-4-yl]methyl]-4-[(2,5-dioxopyrrol-1-yl)methyl]cyclohexane-1-carboxamide
|
| HS Tariff Code |
2934.99.9001
|
| Storage |
Powder -20°C 3 years 4°C 2 years In solvent -80°C 6 months -20°C 1 month Note: Please store this product in a sealed and protected environment (e.g. under nitrogen), avoid exposure to moisture and light. |
| Shipping Condition |
Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)
|
| Solubility (In Vitro) |
DMSO: 200 mg/mL (188.29 mM)
|
|---|---|
| Solubility (In Vivo) |
Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples.
Injection Formulations
Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline)(e.g. IP/IV/IM/SC) *Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution. Injection Formulation 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline) Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil) Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals). View More
Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)] Oral Formulations
Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium) Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals). View More
Oral Formulation 3: Dissolved in PEG400 (Please use freshly prepared in vivo formulations for optimal results.) |
| Preparing Stock Solutions | 1 mg | 5 mg | 10 mg | |
| 1 mM | 0.9414 mL | 4.7072 mL | 9.4143 mL | |
| 5 mM | 0.1883 mL | 0.9414 mL | 1.8829 mL | |
| 10 mM | 0.0941 mL | 0.4707 mL | 0.9414 mL |
*Note: Please select an appropriate solvent for the preparation of stock solution based on your experiment needs. For most products, DMSO can be used for preparing stock solutions (e.g. 5 mM, 10 mM, or 20 mM concentration); some products with high aqueous solubility may be dissolved in water directly. Solubility information is available at the above Solubility Data section. Once the stock solution is prepared, aliquot it to routine usage volumes and store at -20°C or -80°C. Avoid repeated freeze and thaw cycles.
Calculation results
Working concentration： mg/mL；
Method for preparing DMSO stock solution： mg drug pre-dissolved in μL DMSO (stock solution concentration mg/mL). Please contact us first if the concentration exceeds the DMSO solubility of the batch of drug.
Method for preparing in vivo formulation:：Take μL DMSO stock solution, next add μL PEG300, mix and clarify, next addμL Tween 80, mix and clarify, next add μL ddH2O，mix and clarify.
(1) Please be sure that the solution is clear before the addition of next solvent. Dissolution methods like vortex, ultrasound or warming and heat may be used to aid dissolving.
(2) Be sure to add the solvent(s) in order.
Products are for research use only; We do not sell to patients
Copyright 2020 InvivoChem LLC | All Rights Reserved
