Exosomes in tears of healthy individuals: Isolation, identification, and characterization


Cite item

Full Text

Open Access Open Access
Restricted Access Access granted
Restricted Access Subscription Access

Abstract

Exosomes represent a sort of extracellular vesicles, which transfer molecular signals in the body and contain markers of the exosome-producing cell. This study was aimed at search of exosomes in the tears of healthy humans, validation of their nature and examination of their morphological and molecular-biological characteristics. Samples of the tears individually collected from 24 healthy donors (aged 45–60 years) were centrifuged at 20000 g for 15 min to pellet cell debris. The supernatants were examined in an electron microscope using negative staining and were also used for isolation and purification of exosomes by filtration (100 nm pore-size) and double ultracentrifugation (90 min at 100000 g, 4°C). Resultant pellets were investigated by electron microscopy and immunolabeling, RNA and DNA were isolated and their sizes were determined by capillary electrophoresis, concentration and localization of nucleic acids in the isolated exosomes were studied. DNA sequencing was performed using MiSeq (Illumina, USA), data were analyzed using CLC GW 7.5 (Qiagen, USA). Sequences were mapped on human genome (hg19). Supernatants of the tears contained cell debris, spherical microparticles (20–40 nm), and vesicles; some of the vesicles had morphology and sizes corresponding to exosomes. The pellets obtained after ultracentrifugation of tears contained microparticles (17%), spherical and cup-shaped vesicles (40–100 nm, 83%), which were positive for CD63, CD9, and CD24 receptors (specific markers of exosomes). The study revealed high concentrations of exosomes in human tears; these exosomes contained both RNA (of less than 200 nucleotides in size) and DNA (of 3–9 kb in size). DNA sequencing demonstrated that about 92% of the reads was mapped to human genome.

About the authors

A. E. Grigor’eva

Institute of Chemical Biology and Fundamental Medicine (ICBFM)

Email: lenryab@yandex.ru
Russian Federation, pr. Lavrent’eva 8, Novosibirsk, 630090

S. N. Tamkovich

Institute of Chemical Biology and Fundamental Medicine (ICBFM); Novosibirsk State University

Email: lenryab@yandex.ru
Russian Federation, pr. Lavrent’eva 8, Novosibirsk, 630090; Novosibirsk

A. V. Eremina

Novosibirsk Branch

Email: lenryab@yandex.ru
Russian Federation, Novosibirsk

A. E. Tupikin

Institute of Chemical Biology and Fundamental Medicine (ICBFM)

Email: lenryab@yandex.ru
Russian Federation, pr. Lavrent’eva 8, Novosibirsk, 630090

M. R. Kabilov

Institute of Chemical Biology and Fundamental Medicine (ICBFM)

Email: lenryab@yandex.ru
Russian Federation, pr. Lavrent’eva 8, Novosibirsk, 630090

V. V. Chernykh

Novosibirsk Branch

Email: lenryab@yandex.ru
Russian Federation, Novosibirsk

V. V. Vlassov

Institute of Chemical Biology and Fundamental Medicine (ICBFM)

Email: lenryab@yandex.ru
Russian Federation, pr. Lavrent’eva 8, Novosibirsk, 630090

P. P. Laktionov

Institute of Chemical Biology and Fundamental Medicine (ICBFM)

Email: lenryab@yandex.ru
Russian Federation, pr. Lavrent’eva 8, Novosibirsk, 630090

E. I. Ryabchikova

Institute of Chemical Biology and Fundamental Medicine (ICBFM)

Author for correspondence.
Email: lenryab@yandex.ru
Russian Federation, pr. Lavrent’eva 8, Novosibirsk, 630090

Supplementary files

Supplementary Files
Action
1. JATS XML

Copyright (c) 2016 Pleiades Publishing, Ltd.