Where Do Exosomes Come From? Comparing Common Sources

When comparing exosome products, particle count gets a lot of attention.

But there's another question buyers should ask:

Where did the exosomes actually come from?

Exosomes are a subtype of extracellular vesicle, or EV. EVs are naturally released by cells and can be found in biological fluids. They can also be collected from cells grown under controlled laboratory conditions.

So two products both marketed as “exosomes” can begin with very different biological materials and follow very different manufacturing processes.

Understanding the source helps you understand what you're actually comparing.

Source #1: Amniotic Fluid

Amniotic fluid is the biological fluid surrounding a developing fetus during pregnancy. Research has identified and characterized extracellular vesicles and exosomes naturally present in human amniotic fluid.

According to information supplied by KWEHEALTH, HydroKarma begins with human amniotic fluid obtained from scheduled C-sections. Rather than growing cells in culture to produce EVs, its manufacturing process begins with a biological fluid in which EVs already naturally occur.

Those naturally occurring EVs can then be isolated, purified and concentrated into a finished preparation. Published research has demonstrated the isolation and concentration of extracellular vesicles directly from human amniotic fluid.

Importantly, EVs are not the only signaling components present in HydroKarma. According to information supplied by KWEHEALTH, the finished product contains extracellular vesicles along with growth factors, cytokines and other signaling molecules.

That distinction becomes particularly relevant when comparing an amniotic-fluid-derived product with other approaches such as cultured-cell-derived EVs or PRP.

Source #2: Cultured Stem Cells

Another common approach is to grow stem cells under controlled laboratory conditions and collect the extracellular vesicles those cells release into the surrounding culture environment.

For these products, buyers should consider the original cell source, culture conditions, how many times the cells have been passaged, how cellular aging or senescence is controlled, and how the released EVs are collected and purified.

These questions matter because cells can change during repeated laboratory expansion, and those changes can affect the extracellular vesicles they release.

Passage history and culture conditions are therefore important considerations for cultured-cell-derived products.

HydroKarma follows a different pathway. According to KWEHEALTH, its EV-production process begins directly with amniotic fluid rather than cultured-cell expansion.

Source #3: Blood and Platelets

Blood and platelets are another source of extracellular vesicles.

This is particularly relevant to platelet-rich plasma, or PRP. Activated platelets release extracellular vesicles along with growth factors, cytokines and other signaling molecules.

HydroKarma's amniotic-fluid-derived product likewise contains this broader mixture of signaling components rather than extracellular vesicles alone, as described under Source #1 above.

The major difference is where those components come from.

With PRP, the patient is the biological starting material. The preparation depends on that individual's blood and platelets, which introduces patient-to-patient variability.

Age is one of those variables.

Research has found that increasing patient age is associated with changes in final PRP platelet concentration, while other research has reported age-related differences in platelet biology and functional quality.

A 2026 systematic review and meta-regression of randomized knee-osteoarthritis trials also found that younger age was associated with greater short-term improvement in knee function, although the researchers cautioned that the independent contribution of age remains uncertain.

That doesn't mean PRP becomes ineffective at a particular age. It does mean PRP from younger and older patients should not automatically be assumed to have identical biological characteristics or performance.

HydroKarma takes a different approach. Rather than relying on each recipient's platelets to create the preparation, it begins with human amniotic fluid obtained from scheduled C-sections, and according to KWEHEALTH the extracellular-vesicle component of that finished product can be concentrated, characterized and documented.

For a deeper comparison, see Exosomes vs. PRP: What's the Difference?.

Why Source Transparency Matters

Knowing the source helps you understand both the biology behind a product and the manufacturing questions that matter.

A cultured-cell-derived product raises questions about cell source, culture conditions and passage history. PRP depends on the individual patient's blood and platelets. HydroKarma, according to KWEHEALTH, begins with human amniotic fluid obtained from scheduled C-sections.

But source is only the beginning. Buyers should also look at how the finished product is processed, characterized, tested and documented.

Our related article How Are Exosomes Produced and Processed? takes a closer look at what happens between biological sourcing and the finished product.

The Bottom Line

Not all exosome products begin in the same place.

Cultured-cell products collect EVs released by cells grown in laboratory culture. PRP relies on the patient's own blood and platelets, bringing individual biological variables—including age—into the preparation.

HydroKarma takes the amniotic-fluid route. According to KWEHEALTH, it begins with human amniotic fluid obtained from scheduled C-sections and contains extracellular vesicles along with growth factors, cytokines and other signaling molecules.

The source doesn't tell you everything about a finished product, but it tells you what questions to ask next.

Before buying, don't just ask:

“How many exosomes are in it?”

Ask:

“Where did they come from, how were they processed, and what documentation backs up the finished product?”