The evidence library

The research, read honestly.

This library summarizes independent, published research on mesenchymal stromal/stem cells and extracellular vesicles. It is educational — we link to the original source for every entry so you can read it yourself. We include preclinical (laboratory and animal) work alongside human studies, because being honest about the evidence means showing where it is early, mixed or still open.

Human clinicalOrthopedics

Umbilical Cord-Derived Mesenchymal Stromal Cells (MSCs) for Knee Osteoarthritis: Repeated MSC Dosing Is Superior to a Single MSC Dose and to Hyaluronic Acid in a Controlled Randomized Phase I/II Trial

Stem Cells Translational Medicine · 2019

Evidence type: Human clinical
Cell source: Umbilical cord
Study design: Randomized controlled trial
Population: 26 adults with symptomatic knee OA

What researchers investigated: Whether intra-articular injection of umbilical cord-derived MSCs — given as a single dose or as two repeated doses — was safe and how it compared to hyaluronic acid over 12 months in people with knee osteoarthritis.
What they found: The authors reported no severe adverse events. Only the MSC-treated groups showed significant improvement in pain and function from baseline, and the repeated-dose group reported lower pain scores than the hyaluronic acid group at 12 months. No differences were detected on MRI.
Important limitation: A small phase I/II trial (26 participants across three arms), single-center, and not blinded. Several authors declared employment or intellectual-property ties to the cell-therapy company involved. Larger, blinded trials are needed to confirm the findings.

Original publication

Human clinicalOrthopedics

Treatment of Knee Osteoarthritis With Allogeneic Bone Marrow Mesenchymal Stem Cells: A Randomized Controlled Trial

Transplantation · 2015

Evidence type: Human clinical
Cell source: Bone marrow (allogeneic)
Study design: Randomized controlled trial
Population: 30 adults with chronic knee OA

What researchers investigated: The feasibility, safety, and efficacy of a single intra-articular injection of allogeneic (donor) bone-marrow MSCs versus hyaluronic acid in patients with chronic knee osteoarthritis, followed for one year.
What they found: The authors reported that the treatment was feasible and safe, and that MSC-treated patients showed greater improvement in pain and function scores than the hyaluronic acid group. Quantitative MRI (T2 mapping) indicated improved cartilage quality in the MSC group.
Important limitation: A small trial (15 patients per arm) with a one-year follow-up and an active comparator rather than a placebo. Findings are preliminary indications of efficacy, not confirmation, and require larger studies.

Original publication

Human clinicalSafety

Safety of cell therapy with mesenchymal stromal cells (SafeCell): a systematic review and meta-analysis of clinical trials

PLoS One · 2012

Evidence type: Human clinical
Cell source: Multiple / mixed sources
Study design: Systematic review
Population: 36 studies, 1,012 participants

What researchers investigated: A systematic review and meta-analysis pooling clinical trials that delivered MSCs into the bloodstream (intravenously or intra-arterially), to characterize the safety profile across a range of conditions.
What they found: Across the pooled trials the authors did not detect an association between MSC administration and acute infusional toxicity, organ-system complications, infection, death, or malignancy. The one significant association identified was with transient fever.
Important limitation: The authors concluded MSC therapy 'appears safe' but noted that larger controlled trials with rigorous adverse-event reporting are needed. Covers intravascular delivery through mid-2011 and does not address every cell source, dose, or route.

Original publication

PreclinicalStem Cell Biology

Minimal criteria for defining multipotent mesenchymal stromal cells. The International Society for Cellular Therapy position statement

Cytotherapy · 2006

Evidence type: Preclinical
Cell source: Not applicable
Study design: Narrative review
Population: Not applicable (laboratory/consensus)

What researchers investigated: A position statement from the International Society for Cellular Therapy proposing a minimum set of standard criteria for defining human mesenchymal stromal cells, so that results could be compared across laboratories.
What they found: The committee proposed three criteria: cells must be plastic-adherent in standard culture; must express CD105, CD73 and CD90 while lacking CD45, CD34, CD14/CD11b, CD79α/CD19 and HLA-DR; and must differentiate into osteoblasts, adipocytes and chondroblasts in vitro.
Important limitation: A consensus definition rather than an experimental study, and the authors expected the criteria to be revised as knowledge advanced. It standardizes characterization; it does not establish any clinical benefit.

Original publication

PreclinicalExtracellular Vesicles

Minimal information for studies of extracellular vesicles 2018 (MISEV2018): a position statement of the International Society for Extracellular Vesicles and update of the MISEV2014 guidelines

Journal of Extracellular Vesicles · 2018

Evidence type: Preclinical
Cell source: Not applicable
Study design: Narrative review
Population: Not applicable (laboratory/consensus)

What researchers investigated: A consensus position statement from the International Society for Extracellular Vesicles establishing recommended standards for the nomenclature, separation, characterization and functional analysis of extracellular vesicles (which include exosomes).
What they found: The guidelines set out reporting expectations — including protein-marker validation and documentation of functional activity — intended to improve reproducibility and rigor across extracellular-vesicle research, with a summary checklist for researchers.
Important limitation: A methodological framework authored by a large expert consortium, not a clinical study. It governs how EV research should be reported and makes no claim about any therapeutic effect.

Original publication

Human clinicalSkin & Aesthetics

Combination Treatment with Human Adipose Tissue Stem Cell-derived Exosomes and Fractional CO2 Laser for Acne Scars: A 12-week Prospective, Double-blind, Randomized, Split-face Study

Acta Dermato-Venereologica · 2020

Evidence type: Human clinical
Cell source: Adipose-derived (exosomes)
Study design: Randomized controlled trial
Population: 25 adults with atrophic acne scars

What researchers investigated: Whether an adipose-stem-cell-derived exosome gel applied after fractional CO2 laser resurfacing improved atrophic acne scars, using a split-face design where each patient's other side received a control gel.
What they found: The authors reported a significantly greater reduction in acne-scar scores on the exosome-treated side than the control side (32.5% vs 19.9%), along with milder post-treatment redness and shorter downtime on the exosome side.
Important limitation: A small single-center study (25 patients) using adipose-derived exosomes as an adjuvant to laser treatment. It does not isolate exosomes as a standalone therapy, and results may not generalize to other exosome sources or indications.

Original publication

These studies investigate mesenchymal stromal/stem cells and extracellular vesicles as a scientific field. They are not studies of Stem Nova Direct products, and their results do not establish that any product offered through Stem Nova Direct treats, cures or improves any condition. Study inclusion does not imply endorsement of any outcome.

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