Enrichment of circulating tumor-derived extracellular vesicles from human plasma.
J Immunol Methods
; 490: 112936, 2021 03.
Article
em En
| MEDLINE
| ID: mdl-33242493
ABSTRACT
Extracellular vesicles (EVs) are gaining considerable traction within the liquid biopsy arena, as carriers of information from cells in distant sites that may not be accessible for biopsy. Therefore, there is a need to develop methods to enrich for specific EV subtypes, based on their cells of origin. Here we describe the development of an automated method to enrich tumor-derived EVs from plasma using the CellSearch technology compared to Total EVs isolated using differential ultracentrifugation (DUC). We use a modified CellSearch protocol to enrich EpCAM+ EVs from the plasma of patients with non-small cell lung carcinoma (NSCLC) and triple negative breast cancer (TNBC). As a test case, we examined PD-L1, an immune checkpoint ligand known to be expressed in some tumor tissues, to demonstrate enrichment for EpCAM+ EVs. For this purpose, we developed two custom immunoassays utilizing the Simoa HD-1 analyzer (Quanterix) to detect PD-L1 in EVs and interrogate specific EV populations from human plasma. PD-L1 was present in Total EVs from the plasma of healthy individuals and cancer patients, since it is also expressed on several immune cells. However, EpCAM+ EVs were only detectable from the plasma of cancer patients, suggesting these are tumor-derived EVs. As low as 250 µL of plasma could be used to reliably detect PD-L1 from patient-derived EpCAM+ EVs. In summary, this report demonstrates the development of a robust tumor-derived EV enrichment method from human blood. Furthermore, this proof-of-concept study is extendable to other known cancer-specific proteins expressed on EVs exuded from tumors.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Plasma
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Imunoensaio
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Carcinoma Pulmonar de Células não Pequenas
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Células Epiteliais
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Antígeno B7-H1
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Neoplasias de Mama Triplo Negativas
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Vesículas Extracelulares
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Neoplasias Pulmonares
Limite:
Humans
Idioma:
En
Revista:
J Immunol Methods
Ano de publicação:
2021
Tipo de documento:
Article
País de afiliação:
Estados Unidos