What are Exosomes? | Exosome Definition

What are exosomes? For many years, exosomes were considered to be transporters of cellular waste, but they are now recognized for their essential role in intercellular communication and transportation.

In this article:

• Definition of Exosomes
• Exosome Size
• Exosome Sources
• Exosome Characteristics
• Exosome Review
• Exosome Research
• Cancer Exosomes
• Exosome Therapeutics
• First EV Therapeutic Entering Human Trial
• Exosome Market
• Exosome Global Strategic Report

Exosomes are defined as small vesicles ranging from 30-100nm in size that are found in nearly all eukaryotic fluids and facilitate a range of important cellular functions. They transfer DNA, RNA, and proteins to other cells, thereby altering the function of the target cells.

The diameter of exosomes can range from 30 nm on the low end to 100 nm on the high end. Because exosomes have a low refractive index and are less than 100 nm in diameter, the separation of exosomes from similar sized cells and vesicles can be a challenge.

For this reason, the isolation of pure populations of exosomes may involve physical techniques based on size and density, as well as techniques that utilize biochemical parameters.

Exosomes are present in nearly all body fluids, including:

• Blood
• Urine
• Saliva
• Synovial fluid
• Amniotic fluid
• Semen
• Vaginal fluid
• Breast milk
• Serum and plasma from cancer patients
• Cultured medium of cell cultures
• And more

Exosomes are characterized by the following features:

• Range from 30-100nm in size
• Found in nearly all bodily fluids
• Exported by all eukaryotic cell types
• Exosome properties reflect the donor cell
• Produced in extremely abundant amounts

A review of exosome activity reveals that there has been a explosion in scientific research in recent years. For decades, exosomes were considered extracellular byproducts, but these nano-sized vesicles are now becoming increasingly recognized for their critical role in intercellular communication for both healthy and diseased cell types.

Exosomes have an extraordinary ability to transfer proteins, DNA, mRNA, non-coding RNAs.

Substantial research suggests that understanding the role of cancer exosomes will be critical to the future of human health, because exosomes have the potential to be used in cancer prevention, diagnosis, and therapeutic care.

#Exosomes are in the news again, this time involved with Alzheimer’s disease progression through amyloid-beta oligomers. As stated by the researchers, “Our results imply that exosomes are centrally involved in #Alzheimer’s disease…” https://t.co/5d4aL9VNHL #neurodegenerative pic.twitter.com/ASPnvpmabN

— BioInformant (@StemCellMarket) June 25, 2018

Exosome research are being rapidly explored within academic research settings and private industry. When exosome publications are analyzed, U.S. authors have published approximately 40% of the articles and China takes second place.

However, when the term “exosome” is searched in the scientific literature, Dr. Susanne Gabrielsson from the Karolinska Institutet in Sweden is the leading author with 37 articles.

When the term “extracellular vesicles” is searched, Unicyte AG, a regenerative medicine unit of Fresenius Medical Care, takes the lead. The company has published 100+ papers on exosomes and extracellular vesicles in collaboration with Professor Giovanni Camussi.

Most recently on July 30, 2018, Fresenius Medical Care announced that Unicyte AG achieved a key preclinical milestone in its regenerative medicine program for chronic kidney disease. The company confirmed the “disease modifying potential for its proprietary nano-Extracellular Vesicles…in a second preclinical model of chronic kidney disease.” nEVs are stem cell-derived particles that support cell-to-cell communication.

Exosomes are released in high quantities from rapidly growing cells, including all forms of cancer. It is known that cancer exosomes contribute to metastasis through intercellular communication.

Although exosomes are produced by all cells to facilitate bodily functions, on a cell-for-cell basis, cancer cells release larger quantities of exosomes.

Cancer exosomes are also unique, because they are surrounded by protein “ribbons” known as chaperones.  While these ribbons can vary in size and shape on the surface of exosomes from different types of rapidly growing cells, they are always present.

Because exosomes exhibit biomarkers specific to the cancerous cells that have released them, exosomes also have great potential to be used within theranostic applications. Theranostics is a field of medicine that provides patient-specific therapy based on findings from targeted diagnostic tests.

Finally, cancer exosomes have great potential to be used within diagnostic tools and liquid biopsies for non-invasive detection of cancer.

In summary, there are three broad applications of exosomes in cancer:

1. Exosomes facilitate cancer activity, including tumor formation (tumorigenesis), spread (metastasis), blood vessel growth (angiogenesis), and immune evasion
2. Cancer exosomes can be used as biomarkers within diagnostic tools
3. Cancer exosomes can be used to select targeted treatments for cancer patients based on their unique disease progression

Exosomes are gaining momentum within the medical research community as a type of cell-free therapeutic. For many cell types, exosomes may provide the needed therapeutic effects without the risks of administering cells to patients.

For this reason, there are now more than a dozen companies developing therapeutics that leverage exosomes and other types of extracellular vesicles (EVs).

These companies include Aegle Therapeutics, Anjarium Biosciences, Capricor Therapeutics, Codiak Biosciences, Creative Medical Technology Holdings, Everkine Corporation, Evox Therapeutics, Exogenus Therapeutics, Kimera Labs, ReNeuron, and Unicyte AG (a subsidiary of Fresenius Medical Care), among others.

Aegle Therapeutics deserves recognition as the first extracellular vesicle (EV) company to be cleared by the FDA to enter clinical trials in humans.

In May 2018, Aegle announced that the FDA cleared its first Investigational New Drug (IND) application to initiate a clinical trial in severe second degree burn patients. The company plans to launch a Phase 1/2a clinical trial of its lead product AGLE-102 in late 2018.

Aegle is utilizing allogeneic bone marrow mesenchymal stem cell (BM-MSC) derived extracellular vesicles. It has two products under development, AGLE-102 for burn treatment and AGLE-103 for the management of epidermolysis bullosa (EB).

The exosome market is defined as the market for products and services that leverage exosomes. It is positioned for exponential growth, because exosomes can be leveraged as:

• Research tools
• Diagnostic tools
• Therapeutic messengers (cell-free therapies)
• Agents for use within cosmeceutical products (cosmetics that claim to have medicinal properties, such as anti-aging)

Substantial growth is expected for the market as exosomes get integrated into the fields of liquid biopsy, precision medicine and regenerative medicine.

The “Market for Stem Cell Exosomes” is a 134-page global strategic report about the exosome industry published by BioInformant.  If you are operating within the cell and gene therapy (CGT) industry, you need to understand this exponential growth sector.

With exosomes being credited for the therapeutic effects of many cell types, this report reveals trend rate data for exosome patents, grants, scientific publications, and clinical trials. It explores growing demand for exosome therapeutics, diagnostics, research tools, consumer care products, and manufacturing.

It identifies the five market segments forming the industry, reveals the market player competing in each niche, and presents market size determinations with 5-year projections.

View the report details at this link.

Learn More about Exosomes

For additional insights, watch this excellent overview video exploring, “What is an Exosome?”

Have questions about exosomes and their role in medicine? Ask them in the comments below.