Investigation of microvesicle uptake by mouse lung-marginated monocytes in vitro.
File(s)Bio-protocol4307.pdf (2.64 MB)
Published version
Author(s)
Tan, Ying Ying
O'Dea, Kieran P
Patel, Brijesh V
Takata, Masao
Type
Journal Article
Abstract
Extracellular microvesicles (MVs) are released into the circulation in large numbers during acute systemic inflammation, yet little is known of their intravascular cell/tissue-specific interactions under these conditions. We recently described a dramatic increase in the uptake of intravenously injected MVs by monocytes marginated within the pulmonary vasculature, in a mouse model of low-dose lipopolysaccharide-induced systemic inflammation. To investigate the mechanisms of enhanced MV uptake by monocytes, we developed an in vitro model using in vivo derived monocytes. Although mouse blood is a convenient source, monocyte numbers are too low for in vitro experimentation. In contrast, differentiated bone marrow monocytes are abundant, but they are rapidly mobilized during systemic inflammation, and thus no longer available. Instead, we developed a protocol using marginated monocytes from the pulmonary vasculature as an anatomically relevant and abundant source. Mice are sacrificed by terminal anesthesia, the lungs inflated and perfused via the pulmonary artery. Perfusate cell populations are evaluated by flow cytometry, combined with in vitro generated fluorescently labelled MVs, and incubated in suspension for up to one hour. Washed cells are analyzed by flow cytometry to quantify MV uptake and confocal microscopy to localize MVs within cells (O'Dea et al., 2020). Using this perfusion-based method, substantial numbers of marginated pulmonary vascular monocytes are recovered, allowing multiple in vitro tests to be performed from a single mouse donor. As MV uptake profiles were comparable to those observed in vivo, this method is suitable for physiologically relevant high throughput mechanistic studies on mouse monocytes under in vitro conditions. Graphic abstract: Figure 1. Schematic of lung perfusate cell harvest and co-incubation with in vitro generated MVs. Created with BioRender.com.
Date Issued
2022-02-05
Date Acceptance
2021-11-29
Citation
Bio-protocol, 2022, 12 (3), pp.1-1
ISSN
2331-8325
Publisher
Bio-Protocol
Start Page
1
End Page
1
Journal / Book Title
Bio-protocol
Volume
12
Issue
3
Copyright Statement
© 2022 The Authors; exclusive licensee Bio-protocal LLC.
Sponsor
CW+
Identifier
https://www.ncbi.nlm.nih.gov/pubmed/35284602
PII: 4307
Grant Number
Award 0096
Subjects
Extracellular vesicles
Lungs
Microvesicles
Monocytes
Sepsis
Publication Status
Published
Coverage Spatial
United States
Date Publish Online
2022-02-05