Exo-FBS ™ Exosome-depleted FBS
- CD63 and exosome-sized vesicles are removed
- No bovine exosomes detectable by Western blot
- No bovine microRNA detectable by qPCR
- Same cell growth rates supported as standard FBS
- Growth rate higher than FBS depleted in exosomes from other suppliers
- Use the same as standard FBS (add 10% in DMEM or RPMI)
- Optimized for exosome research with numerous peer-reviewed publications
Exosomes are 60-120 nm membrane vesicles secreted by most cell types in vivo and in vitro. Exosomes are found in blood, urine, amniotic fluid, malignant ascites fluids, urine, and cultured cell media. Exosomes contain different subsets of microRNAs depending on the type of cell from which they are secreted. The standard growth medium for most cells in culture requires Fetal Calf Serum (FBS) as a growth supplement for DMEM.
FBS is derived from bovine (cow) serum and contains a high abundance of exosomal cow vesicles. These exosomes can interfere with or cause significant background problems when studying the secreted exosomes of their cells of interest under standard culture conditions. SBI has developed an exosome-depleted FBS growth supplement called Exo-FBS that has been stripped of bovine exosomes.
Exo-FBS supports the equivalent growth of many cell types in culture, contains very low levels of cow CD63-positive exosomes, and does not have any measurable bovine microRNAs. Conduct your studies of cell-secreted exosomes in culture without the concern of contaminating cow exosomes in your experiments. Ultracentrifugation is not required. Available as a standard FBS supplement or a heat-inactivated FBS medium supplement (treated at 65 ° C for 15 minutes prior to removal of the bovine exosome) in two sizes, each.
Exo-FBS supports more robust cell growth health than the competition
Exo-FBS supports more robust cell growth than exosome-depleted FBS from Company G. HepG2 cells were grown in medium containing standard (control) FBS, Exo-FBS, or exosome-depleted FBS from Company G. The Data are shown after one and two passages and illustrate that Exo-FBS provides a higher number of viable cells (left panel, viability assessed by a CCK-8 assay) and healthier cell morphology (right panel) than the Company’s product. G.
Exosomes removed in Exo-FBS
NanoSight Particle Analysis of FBS and Exo-FBS: Standard FBS and Exo-FBS samples were diluted 1: 1000 and then analyzed for particle size and abundance using a NanoSight LM10 instrument. The FBS standard sample shows a significant amount of exosome-sized microvesicles where the Exo-FBS exosome-depleted FBS sample has a drastic reduction in exosome particles.
Exo-FBS is depleted of bovine CD63 exosomes: Tetraspanin CD63 protein is a common marker for exosomes. We used a bovine-specific anti-CD63 antibody to develop an enzyme-linked immunosorbent assay (ELISA). Equal volumes (50 ul) of standard FBS or Exo-FBS depleted medium supplement were used in this ELISA. The amounts of CD63-positive bovine exosomes were drastically reduced. The results are plotted and normalized to the standard FBS signal level.
Bovine microRNAs are absent in Exo-FBS
FBS and Exo-FBS standard media supplements (4 ml) were treated with Trizol extraction methods to recover RNA from exosomes. RNA was converted to cDNA and 72 individual bovine microRNAs were measured by qPCR using SBI’s QuantiMir system. Of the 72 microRNAs tested, 12 produced amplification curves in the FBS sample but not in the Exo-FBS sample. Bovine microRNAs present in FBS is no longer detectable in Exo-FBS – No more cow microRNAs.
Exo-FBS medium supports robust cell growth in culture equal to standard FBS medium
Complete medium with 10% standard FBS or 10% Exo-FBS supplement. HT1080 fibrosarcoma cells, PC-3 prostate cancer cells, MCF-7 breast cancer cells and HEK293 cells were seeded in 10,000 or 20,000 cells and then cultured under standard conditions at 37 ° C with 5% CO2 for 5 days in the indicated medium. Cells were imaged to determine growth numbers and morphologies.
Equivalent morphologies and growth were observed for the standard FBS and Exo-FBS media tested in these 4 tested cell lines. If you think one company’s exosome-depleted FBS is like another, take a look at the data above. Exo-FBS clearly supports better growth than exosome-depleted FBS from Company G. Whether you are looking at cell viability or cell morphology, Exo-FBS is the obvious reagent of choice for robust cell growth for extracellular vesicle studies.