Exosomes are the smallest and most characteristic of
extracellular vesicles and contain a variety of biological
information, including proteins, lipids, DNA, mRNA, and microRNA.
These biomolecules are involved in regulating various life
activities such as signal transduction, proliferation, migration,
and angiogenesis among tumor cells. Exosomes are not only a new
biological marker assay, but also provide potential molecular
therapeutic targets and are expected to be a carrier for anti-brain
tumor drug delivery.
Exosome for brain tumors
The use of peripheral blood biomarkers is particularly important to
assist in determining brain tumor recurrence and evaluating
treatment response. Exosomes readily cross the blood-brain barrier
into and out of the central nervous system. Alfa Oncology can
detect specific sequence changes in DNA isolated from brain tumor
patient samples (e.g., peripheral blood extracellular vesicles from
glioma patients) to identify potential biological markers. RNAs
(including miRNAs and lncRNAs) obtained from peripheral blood or
body fluid exosomes are more abundant and tumor-specific.
Therefore, we looked for proteins that were highly expressed by
observing the expression profiles of exosomal miRNA and lncRNA in
brain tumors (glioblastoma) compared with normal tissues as
biological markers for the diagnosis of glioblastoma.
Service for isolation and identification of exosomes of brain
tumor origin
We select different exosome isolation methods for different
isolation purposes, including the isolation and purification of
brain tumor-derived exosomes from biological fluid samples such as
cell culture supernatants and patient plasma using ultrafast
differential centrifugation, ultrafiltration, OptiPrep density
gradient centrifugation, and immunoprecipitation (IP). With
appropriate methods, we can isolate and obtain relatively
uniform-sized microvesicular populations with high specificity and
no impact on the subsequent analysis of the results.
We understand the biological activity of exosomes by measuring the
size of vesicle particles and the expression levels of specific
proteins TSG101, ALIX, or myelin proteolipid protein (PLP) on their
membrane surface. We can combine multiple proteins as exosome
markers, such as ALIX, TSG101, CD63, CD60, CD9, and CD81, and then
use mass spectrometry analysis to perform a comprehensive screening
of the proteome of exosomes, and observe the size and morphology of
exosomes by fluorescence and electron microscopy.