In Vivo | Collagen Hybridizing Peptides, sulfo-Cy7.5 Conjugates (sCy7.5-CHP)

The collagen hybridizing peptide (CHP) is a novel and unique peptide that specifically binds unfolded collagen chains, both in vitro and in vivo.[1,2,3] By sharing the Gly-X-Y repeating sequence of natural collagen, CHP has a strong capability to hybridize with denatured collagen chains by reforming the triple helical structure, in a fashion similar to DNA fragments annealing to complementary DNA strands. CHP is extremely specific: it has negligible affinity to intact collagen molecules due to lack of binding sites, and it is inert towards non-specific binding because of its neutral and hydrophilic nature.

The in vivo CHP incorporates our newest sequence which allows them to be directly injected into animals without having to pre-activate them with a heating step. [4] Therefore, the in vivo CHPs will always be in their active form and will not self-hybridize once injected. [4] The sCy7.5-CHP is a powerful in vivo tool which enables straightforward detection of inflammation and tissue damage caused by a large variety of diseases, as well as tissue remodeling during development and aging.[3] CHP can measure and localize mechanical injury to collagenous tissue at the molecular level.[5]

The sCy7.5-CHPs are labeled with sulfonated-cyanine 7.5 dye for near-infrared fluorescence (NIRF) detection. This wavelength offers better tissue penetration while minimizing tissue autofluorescence.

Specification

Specificity: CHP binds to the unfolded triple-helical chains of all collagen types (e.g., I, II, III, IV, etc).[3,6]

Applications: in vivo imaging, small animal imaging

Features

• New sequence designed for in vivo use- does not need any pre-activation step unlike CHPs for histology
• Near-infrared imaging probe minimizes the chance of autofluorescence in the gut or certain tissues
• Can be used for systemic or in situ injection
• Signal lasts at target sites for days, allowing for imaging at multiple time points with a single dose
• High affinity and unparalleled specificity to collagen turnover with essentially no nonspecific binding
• Applicable to all types of collagen from all species, relying on collagen's secondary structure instead of any defined sequence for binding
• Stable as powder form, stored at -20 °C

Additional Information

• sCy7.5-CHP dose can be adjusted based on animal model or application. Current dosing is based on a mouse model. Please check the protocol for details

User Guide with FAQ

Citations

• Huang, Kui, et al. "Targeting Molecular Collagen Defects from the Initiation of Knee Osteoarthritis." medRxiv (2024): 2024-06.
• Lab Anim (NY). 2024 Aug;53(8):196-204. doi: 10.1038/s41684-024-01408-0. Epub 2024 Jul 26.
• ACS Nano. 2021 Dec 28;15(12):19138-19149. doi: 10.1021/acsnano.1c07112. Epub 2021 Nov 5.
• J Control Release. 2023 Jan;353:278-288. doi: 10.1016/j.jconrel.2022.10.017. Epub 2022 Dec 1.
• Biochim Biophys Acta Gene Regul Mech. 2023 Jun;1866(2):194928. doi: 10.1016/j.bbagrm.2023.194928. Epub 2023 Mar 21.
• Westenskow, Peter, et al. "Use of collagen-hybridizing peptides to assess active fibrosis in 2 mouse models of choroidal neovascularization." Investigative Ophthalmology & Visual Science 63.7 (2022): 3870-3870.
• Ganji, Elahe. Growth and mechanobiology of the Achilles enthesis in mice. University of Delaware, 2021.
• Mol Pharm. 2017 Jun 5;14(6):1906-1915. doi: 10.1021/acs.molpharmaceut.7b00009. Epub 2017 May 8.