Expression and purification of a native Thy1-single-chain variable fragment for use in molecular imaging.
Sci Rep
; 11(1): 23026, 2021 11 29.
Article
en En
| MEDLINE
| ID: mdl-34845270
ABSTRACT
Molecular imaging using singlechain variable fragments (scFv) of antibodies targeting cancer specific antigens have been considered a non-immunogenic approach for early diagnosis in the clinic. Usually, production of proteins is performed within Escherichia coli. Recombinant proteins are either expressed in E. coli cytoplasm as insoluble inclusion bodies, that often need cumbersome denaturation and refolding processes, or secreted toward the periplasm as soluble proteins that highly reduce the overall yield. However, production of active scFvs in their native form, without any heterologous fusion, is required for clinical applications. In this study, we expressed an anti-thymocyte differentiation antigen-scFv (Thy1-scFv) as a fusion protein with a N-terminal sequence including 3 × hexa-histidines, as purification tags, together with a Trx-tag and a S-tag for enhanced-solubility. Our strategy allowed to recover ~ 35% of Thy1-scFv in the soluble cytoplasmic fraction. An enterokinase cleavage site in between Thy1-scFv and the upstream tags was used to regenerate the protein with 97.7 ± 2.3% purity without any tags. Thy1-scFv showed functionality towards its target on flow cytometry assays. Finally, in vivo molecular imaging using Thy1-scFv conjugated to an ultrasound contrast agent (MBThy1-scFv) demonstrated signal enhancement on a transgenic pancreatic ductal adenocarcinoma (PDAC) mouse model (3.1 ± 1.2 a.u.) compared to non-targeted control (0.4 ± 0.4 a.u.) suggesting potential for PDAC early diagnosis. Overall, our strategy facilitates the expression and purification of Thy1-scFv while introducing its ability for diagnostic molecular imaging of pancreatic cancer. The presented methodology could be expanded to other important eukaryotic proteins for various applications, including but not limited to molecular imaging.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Contexto en salud:
1_ASSA2030
/
3_ND
Problema de salud:
1_geracao_evidencia_conhecimento
/
3_neglected_diseases
/
3_zoonosis
Asunto principal:
Anticuerpos de Cadena Única
/
Imagen Molecular
Tipo de estudio:
Prognostic_studies
/
Screening_studies
Límite:
Animals
/
Humans
Idioma:
En
Revista:
Sci Rep
Año:
2021
Tipo del documento:
Article
País de afiliación:
Estados Unidos