Medical Update – October 2026

Did You Know?

Highlights from this issue

A boost for haploidentical transplantation:

Adding cord blood and MSCs was linked to better five-year survival in aplastic anemia, although larger prospective studies are still needed.

More cells from one cord blood unit:

Expansion technologies can multiply CD34+ cells up to 164-fold and help speed up blood-cell recovery after transplantation.

Choosing an alternative donor

In adolescents and young adults, cord blood was linked to the most favorable five-year survival results, despite slower early blood-cell recovery.

Beyond insulin:

MSC-based therapies may help protect insulin-producing cells and improve glucose control, but researchers still need to make the benefits last longer.

After optic nerve trauma:

MSCs may help protect retinal cells and support nerve repair, but clinical evidence is still limited to small early studies.

A milestone in acute GVHD:

Remestemcel-L became the first FDA-approved MSC therapy, although researchers still need to clarify which patients benefit most and how durable the effect is.

A natural dressing for the eye:

Amniotic membrane can calm inflammation, limit scarring, and support ocular surface healing, although products still need better standardization.

Stronger Together: Umbilical Cord Blood and MSCs Support Transplantation

ADDING CORD BLOOD AND MSCS TO HAPLOIDENTICAL TRANSPLANTATION MAY SUPPORT BETTER LONG-TERM OUTCOMES IN APLASTIC ANEMIA

Think of the bone marrow as the body’s blood-cell factory. In aplastic anemia, this factory slows down or stops, leaving the body with too few blood cells. Hematopoietic stem cell transplantation is one of the treatments that can restore blood-cell production. If a fully matched donor is unavailable, doctors may use a partially matched family member. Researchers asked whether adding cord blood and MSCs could give such a transplant an extra boost. The combined approach did not speed up blood-cell recovery or clearly reduce overall GVHD, but it was linked to better five-year survival and fewer serious complications. The signal is encouraging, although larger prospective studies are needed before this strategy can become standard practice.

Aplastic anemia is a rare, life-threatening condition in which the bone marrow stops producing enough blood cells, often for no clear reason. The two treatments that can offer a cure are immunosuppressive therapy and hematopoietic stem cell transplantation (HSCT). Yet finding a fully matched sibling donor is difficult: around two-thirds of patients do not have one. A haploidentical transplant from a partially matched family member can provide another route, although it brings a risk of graft-versus-host disease (GVHD). Researchers are therefore exploring whether adding mesenchymal stem cells (MSCs) and umbilical cord blood to the transplant could help the donor cells take hold and lower the risk of GVHD.

In 2026, Tan Z and colleagues reported results from a single-center retrospective study designed to test this strategy. They compared haploidentical transplantation alone with transplantation supported by the co-infusion of umbilical cord blood and MSCs.

The analysis included 108 patients who underwent haploidentical HSCT between January 2018 and January 2025; 40 received the additional cord blood and MSC co-infusion. The researchers compared the time to neutrophil and platelet recovery, the incidence of GVHD and viral reactivation, and long-term patient outcomes.

The two groups showed similar rates of blood-cell recovery and GVHD overall. However, patients who received cord blood and MSCs showed a downward trend in grade II–IV acute GVHD and achieved significantly better five-year overall survival and GVHD-free, relapse-free survival (GRFS). These findings suggest that the combined approach may support better long-term outcomes after haploidentical HSCT. Because the study was retrospective and conducted at a single center, larger prospective trials are still needed before firm conclusions can be drawn.

Key points

• An extra boost for transplantation: The study tested whether adding cord blood and MSCs could improve haploidentical HSCT for aplastic anemia.
• Promising long-term results: Among 108 patients, the combined approach was linked to better five-year overall survival and GVHD-free, relapse-free survival.
• Encouraging, but not definitive: Blood-cell recovery and overall GVHD rates were similar, and larger prospective studies are still needed.

Reference:
Tan Z et al. Clinical Outcomes of Haploidentical Transplantation Combined With Umbilical Cord Blood and Mesenchymal Stem Cells Co-Infusion for Aplastic Anemia: A Single-Center Retrospective Study. Transplant Proc. 2026 May;58(4):808-815.
https://pubmed.ncbi.nlm.nih.gov/41982020/

More Cells, Faster Recovery: The New Era of Cord Blood Expansion

SMALL CORD BLOOD UNIT, BIGGER TRANSPLANT POTENTIAL: EXPANSION TECHNOLOGIES CAN MULTIPLY STEM CELLS AND HELP PATIENTS RECOVER FASTER AFTER TRANSPLANTATION

A single cord blood unit contains only a limited number of blood-forming stem cells. This can be enough for a child, but often not for an adult, and a low cell dose can mean slower recovery or even graft failure. Scientists are therefore learning how to grow these cells outside the body before transplantation, while keeping their ability to rebuild the blood system. Some methods increase CD34⁺ cell numbers more than 30-fold, while Notch-based systems have achieved up to 164-fold expansion. Clinical studies show that expanded products can help neutrophils and platelets recover sooner, reducing the vulnerable period after transplantation. One product, NiCord® (omidubicel), is already FDA-approved, and another, Zemcelpro®, has taken an important step toward authorization in Europe. The science is moving fast, but wider use will still depend on reliable large-scale manufacturing, consistent product quality, regulatory safety, and proof that the expanded cells continue to work well over the long term.

In umbilical cord blood transplantation (UCBT), cell dose matters. When the total nucleated cell (TNC) dose is below 2.5 × 10⁷/kg, graft failure can reach 38%, versus about 12% above 5.0 × 10⁷/kg. Two strategies address this limitation: transplanting two cord blood units or expanding hematopoietic stem and progenitor cells (HSPCs) outside the body. A dual-unit transplant raises the median TNC dose to 4.8 × 10⁷/kg but does not speed engraftment. Attention has therefore shifted to ex vivo expansion, which increases HSPC numbers while preserving stem-cell properties. Methods include nicotinamide, copper chelators, stromal co-culture, and Notch signaling activation.

In 2026, Ke Pi and colleagues combined findings from hematopoietic biology, bioengineering, and clinical studies to map the next generation of cord blood expansion platforms. Their goal is to deliver more than 10⁶ CD34⁺ cells/kg, the level linked to reliable adult engraftment without weakening long-term blood-system recovery.

How much can these methods expand CD34⁺ cells? Cytokine-only culture achieves a median 4-fold increase, copper chelation 2.2-fold, nicotinamide more than 30-fold, and MSC co-culture 30.1-fold. Notch-based systems can reach 164-fold expansion and shortened neutrophil engraftment to 16 days in trials. Median recovery was 28 days with cytokines, 30 with copper chelation, 16 with Notch, 11.5 with nicotinamide, and 15 with MSC co-culture. Each method offers a different balance of speed, scale, and complexity.

Co-culture systems aim to recreate the supportive bone marrow environment outside the body. Endothelial cells and MSCs provide hematopoietic progenitor cells with structural, biochemical, and regulatory support. Researchers are also engineering this niche through extracellular-matrix modulation, 3D scaffolds, and bioreactors.

The review also assessed clinical performance. It covered 18 trials, including 13 completed studies, and 559 patients with hematologic malignancies who received expanded cord blood. Strategies included NiCord, UM171, SR-1, PGE2, Notch ligands, valproic acid, tetraethylenepentamine (TEPA), and MSC co-culture.

A major milestone came in April 2023, when the FDA approved NiCord® (omidubicel) for patients aged 12 years and older who require hematopoietic stem cell transplantation. The product uses CD133⁺ cells from one cord blood unit, expanded with nicotinamide (a form of vitamin B3)—and hematopoietic cytokines. In a randomized phase III trial, omidubicel produced faster neutrophil and platelet recovery, fewer infections, and shorter hospital stays than unmanipulated UCB transplantation.

Europe is also advancing. Zemcelpro® (dorocubicel; UM171) combines expanded CD34⁺ HSCs with non-expanded CD34⁻ cells from the same cord blood unit. The European Medicines Agency’s Committee for Medicinal Products for Human Use recommended conditional authorization for adults with blood cancers who need an allogeneic HSC transplant but lack a suitable donor. In phase 1–2 trials, median neutrophil recovery fell to 10–12 days versus 24–28 days in controls; full engraftment was achieved, and one-year survival rose to 75% versus 50–60%.

Another approach uses StemRegenin-1 (SR-1). In the phase I/II NCT01474681 trial, patients received two cord blood units: one with SR-1-expanded HSCs (HSC835) and one unmanipulated. The product was well tolerated, accelerated neutrophil and platelet recovery, and produced sustained engraftment in 11 of 17 patients.

Tetraethylenepentamine (TEPA) has also reached clinical testing. TEPA-expanded CD133⁺ cells were evaluated in phase I/II (NCT01484470) and phase II/III (NCT00469729) trials. Patients achieved neutrophil recovery by day 30, platelet recovery by day 48, and approximately 90% survival at 100 days. Compared with historical controls, the TEPA group showed better 100-day survival, faster myeloid engraftment (21 versus 28 days), and earlier platelet recovery (54 versus 105 days).

MSC-based expansion has also shown encouraging results. Studies paired one MSC-expanded cord blood unit with one unmanipulated unit. In NCT00498316, neutrophil and platelet recovery occurred sooner than with two unmanipulated units: 15 versus 24 days and 40 versus 49 days, respectively. A later phase 3 trial (NCT01854567) again showed faster neutrophil engraftment: 12 versus 16 days.

Together, these findings make cord blood expansion one of the most promising advances in hematologic transplantation. Yet important hurdles remain: methods vary in efficiency, long-term cell function is uncertain, and manufacturing still faces scalability, reproducibility, and regulatory challenges. These barriers limit wider clinical use.

What comes next? Researchers aim to combine multiomics and single-cell tools with gene editing, AI-guided culture optimization, smart bioreactors, personalized and epigenetic strategies, and new small molecules. The goal is to make HSC expansion more efficient, standardized, and clinically effective.

Key points

• More cells, better odds: A low cell dose can delay engraftment and increase the risk of graft failure, especially in adults.
• Expansion can make a big difference: Some platforms increase CD34⁺ cell numbers more than 30-fold, while Notch-based systems have achieved up to 164-fold expansion.
• The technology is reaching patients: NiCord® is FDA-approved, and Zemcelpro® has received a positive recommendation for conditional authorization in Europe.
• What still needs to improve: Wider use will require scalable manufacturing, consistent quality, regulatory confidence, and durable long-term cell function.

Reference:
Pi K et al. Next-Generation Cord Blood Expansion: Bridging the Cell Dose Gap with Bioengineered Niches and Clinical Breakthroughs. Stem Cell Rev Rep. 2026 Apr;22(3):1250-1272. https://pubmed.ncbi.nlm.nih.gov/41612010/

Cord Blood Takes the Lead: Better Survival for Young Transplant Patients

A SLOWER START, BUT STRONGER LONG-TERM RESULTS: CORD BLOOD SHOWS ENCOURAGING SURVIVAL OUTCOMES FOR ADOLESCENTS AND YOUNG ADULTS

When a patient needs a stem cell transplant but has no fully matched sibling, doctors can consider other donor sources. Two important options are banked umbilical cord blood and a haploidentical donor, usually a family member who is only a partial match.A nationwide study compared these approaches in 458 adolescents and young adults. Cord blood transplants took a little longer to start producing new white blood cells, but patients in this group had the most favorable five-year survival results.
Put simply, cord blood may be slower to “switch on,” yet it can still be a strong alternative when a fully matched donor is unavailable. Because this was a retrospective study rather than a randomized trial, the findings are encouraging but do not prove that cord blood is the best choice for every patient.

Finding a fully matched family donor is not easy: in developed countries, only about 30% of patients have an HLA-matched sibling. Fortunately, other donor options can also lead to good outcomes. These include unrelated umbilical cord blood transplantation (UCBT) and haploidentical transplantation, which uses a partially matched family donor. Cord blood has a practical advantage: it is already cryopreserved and can be made available quickly. It is also linked to a lower risk of chronic graft-versus-host disease (GVHD), a complication that remains an important concern after haploidentical transplantation.

In May 2026, researchers published a nationwide retrospective study of allogeneic hematopoietic cell transplantation (HCT) in adolescents and young adults aged 16–25 years. This age group sits at the crossroads of pediatric and adult hematology. Patients may differ in disease biology, other health conditions, tolerance of conditioning regimens, and treatment plans. Moving between pediatric and adult healthcare systems can also influence how donors are selected and which transplantation strategy is used.

Because direct comparisons of alternative donor strategies in this age group are scarce, the study fills an important evidence gap. Researchers compared three transplantation approaches: unrelated umbilical cord blood transplantation (UCBT), haploidentical transplantation without post-transplant cyclophosphamide (non-PTCy-haplo), and haploidentical transplantation with PTCy (PTCy-haplo), which is used to help prevent GVHD. The analysis covered 458 patients: 101 received UCBT, 132 underwent non-PTCy-haplo transplantation, and 225 underwent PTCy-haplo transplantation.

Blood-cell recovery was faster after haploidentical transplantation. Neutrophil engraftment took a median of 20 days with UCBT, 14 days with non-PTCy-haplo, and 16 days with PTCy-haplo. Despite this slower recovery, UCBT showed the most favorable survival results. Five-year overall survival was 79.2% with UCBT, compared with 43.6% for non-PTCy-haplo and 62.1% for PTCy-haplo (log-rank P < 0.001). Five-year relapse-free survival was 71.3%, 40.7%, and 60.2%, respectively (log-rank P < 0.001), while relapse rates were similar. Within 100 days, grade II–IV acute GVHD occurred in 30.7% of the UCBT group, 42.5% of the non-PTCy-haplo group, and 32.1% of the PTCy-haplo group (Gray P = 0.041).

The study offers valuable real-world evidence on alternative donor options for adolescents and young adults—a group still underrepresented in transplantation research. Although neutrophil recovery took longer with UCBT, this strategy was linked to better long-term survival than non-PTCy-haploidentical transplantation. The findings underline that cord blood remains a relevant donor option for adolescents and young adults.

Key points

• Three donor strategies, one key question: The study followed 458 patients aged 16–25 years to compare UCBT with two haploidentical transplantation approaches.
• Slower start, stronger finish: Neutrophil recovery took longer after UCBT, yet this group achieved the most favorable five-year survival results.
• The take-home message: Cord blood remains a compelling donor option, although this retrospective study cannot identify the best choice for every patient.

Reference:
Yanagisawa R et al. Comparative outcomes of umbilical cord blood transplantation versus haploidentical transplantation according to post-transplant cyclophosphamide use in adolescent and young adult patients. Bone Marrow Transplant. 2026 Aug;61(8):996-1005. https://pubmed.ncbi.nlm.nih.gov/42215621/

Beyond Insulin: Can MSCs Help Rewrite the Future of Diabetes Care?

MSCS MAY HELP PROTECT INSULIN-PRODUCING CELLS AND IMPROVE GLUCOSE CONTROL, BUT LONGER-LASTING BENEFITS WILL REQUIRE MORE RESEARCH AND BETTER DELIVERY STRATEGIES

Diabetes is more than a problem with high blood sugar. It also involves chronic inflammation, disrupted immune regulation, and damage to blood vessels. Researchers are therefore exploring whether MSCs could help protect insulin-producing cells, calm harmful immune responses, and improve the way the body controls glucose.
Early studies suggest that MSC-based therapies may improve glucose control, reduce insulin requirements, and support insulin-producing cells in some patients. However, the benefits often weaken after six months. Larger phase III trials and better delivery strategies are needed to determine whether MSC therapy can produce reliable, long-lasting effects.

Diabetes affected 537 million adults worldwide in 2021, according to the International Diabetes Federation. By 2045, this number is expected to rise by 46% to 783 million. Despite major advances in treatment, long-term blood glucose control remains difficult, and type 1 diabetes still has no cure. Diabetes also involves chronic inflammation, disrupted immune regulation, and damage to blood vessels. Researchers are therefore exploring therapies that address more than glucose levels. One promising option is mesenchymal stem cells (MSCs), which can influence immune responses and support tissue repair.

In 2026, Leyi Tu and colleagues published a broad review of MSC-based treatments for diabetes. They examined how MSCs may work, what laboratory and animal studies have shown, how patients have responded in clinical trials, and what still prevents routine use.

MSCs may work in several ways. In type 1 diabetes, they may calm the immune attack and protect insulin-producing β-cells. In type 2 diabetes, they may improve metabolism and help preserve β-cell function. They can also affect chronic inflammation, stress inside cells, and epigenetic changes. MSCs release factors such as VEGF, HGF, and IGF-1, which may protect β-cells and support repair. Under special culture conditions, they can even develop into insulin-producing cells. MSCs may also improve insulin sensitivity and help tissues manage glucose more effectively.

Clinical interest is growing rapidly. A ClinicalTrials.gov search for “mesenchymal stromal cells” AND “diabetes” found 111 registered trials, mostly using MSCs from umbilical cord or bone marrow. Laboratory research and early clinical studies suggest a generally encouraging safety profile and possible benefits. Reported results include HbA1c reductions of at least 1% and cuts in insulin requirements of 50% or more.

Some results are especially notable. Among patients treated with UC-MSCs, 40.7% achieved at least a 10% improvement in fasting C-peptide over 12 months (p < 0.05). Three patients became insulin-independent for 3–12 months, while none did in the control group (NCT04078308). In another study, UC-MSCs were combined with the patient’s own bone marrow mononuclear cells and delivered through the pancreatic artery. This increased the C-peptide area under the curve by 105.7% (p = 0.00012), insulin secretion by 49.3% (p = 0.01), and reduced HbA1c by 12.6% (p < 0.01) (NCT01374854). However, in most trials, the treatment effect fell by 40–60% after six months. Delivery through the pancreatic artery appeared to produce stronger metabolic effects than other routes. Even so, one intravenous dose of donor MSCs also induced clinical remission, supporting the idea of an off-the-shelf therapy. MSC-based treatments are also being studied for diabetic kidney disease, diabetic wounds—including foot ulcers—and diabetic retinopathy.

Before MSC therapy can be widely used for diabetes, researchers need standard treatment protocols, strong phase III trials, and proof that the benefits justify the costs. The main challenge is durability. MSCs often do not survive or settle in the target tissue for long, which may explain why their effects fade. Researchers are testing ways to improve this, including low-oxygen preconditioning, biomaterial encapsulation, and genetic modification.

Key points

• Beyond blood sugar: MSCs may calm inflammation, protect insulin-producing β-cells, and improve insulin sensitivity.
• Encouraging early signals: Studies reported HbA1c reductions of at least 1%, insulin-requirement cuts of 50% or more, and temporary insulin independence in selected patients.
• The durability challenge: Benefits often weaken after six months, so standardized protocols and robust phase III trials are still needed.

Reference:
Tu L et al. The progress and challenges of mesenchymal stromal cell-based therapy for diabetes and its complications. Biol Res. 2026 Mar 16;59(1):26. https://pmc.ncbi.nlm.nih.gov/articles/PMC13104284/

A New Vision for Optic Nerve Repair: Can MSCs Help Restore Sight After Trauma?

MSCS MAY HELP PROTECT INJURED RETINAL CELLS AND SUPPORT OPTIC NERVE REPAIR AFTER TRAUMA, ALTHOUGH EVIDENCE REMAINS AT AN EARLY STAGE

The optic nerve works like a cable, carrying visual signals from the eye to the brain. When trauma damages this cable, sight can be partly or completely lost, and current treatments offer limited help. Researchers are now asking whether MSCs could protect injured retinal cells and support the regrowth of damaged nerve fibres. In two small clinical studies, placental and umbilical cord-derived MSCs were reported to be acceptably safe. Visual acuity improved in four patients treated with placental MSCs, but the evidence is still very limited. The results are encouraging, yet much larger and better-standardized studies are needed before we can know whether MSCs can reliably restore vision after optic nerve injury.

Traumatic optic neuropathy occurs when an injury damages the optic nerve, most often after a road traffic accident. Current treatments, including corticosteroids and surgery, offer limited benefits. This has sparked interest in cell-based therapies that may both protect nerve cells and support the repair of retinal ganglion cells. A recent review by Wang Y and colleagues (2026) brings together the latest progress in this emerging field.

Cell-based treatments are already being studied for corneal blindness, macular degeneration, and retinitis pigmentosa, and researchers are now exploring their potential in traumatic optic neuropathy. Mesenchymal stem cells (MSCs) are especially interesting because they can release neuroprotective and immune-regulating factors that may help retinal ganglion cells survive and encourage damaged axons to regrow. This strategy—protecting injured cells while supporting repair—is often called rescue therapy. MSCs can be obtained from bone marrow, adipose tissue, umbilical cord, or placenta. The first human trial of MSC therapy for traumatic optic neuropathy, reported in 2020, used placental MSCs and highlighted this tissue as a potential source for regenerative treatment.

Several studies have explored whether MSC transplantation can help patients with traumatic optic neuropathy and how the cells might work. The review highlights two clinical trials: one using placental MSCs delivered into the sub-Tenon space around the eye (NCT05147701), and another using umbilical cord-derived MSCs (ChiCTR-TRC-14005093). Both studies reported acceptable safety. Visual acuity improved in all four patients who received placental MSCs, and the same cells also increased axon survival in an optic nerve crush model.

The therapeutic effect of MSCs appears to come mainly from the substances they release. These neurotrophic and immunomodulatory factors may protect injured retinal ganglion cells and support axon survival and regeneration. MSCs also offer practical advantages: they are relatively easy to collect and expand outside the body, and their low immunogenicity and immune-regulating properties make both autologous and donor-derived transplantation possible.

The outlook is promising, but the evidence is still at an early stage. Before cell-based therapies can move into routine care for traumatic optic neuropathy, researchers need stronger preclinical data, standardized methods for preparing and delivering the cells, consistent ways to measure visual and nerve recovery, and clear criteria for selecting patients. These steps will be essential to determine whether the approach can achieve meaningful optic nerve regeneration.

Key points

• A rescue strategy for sight: MSCs may release factors that protect retinal ganglion cells and support the regrowth of damaged axons.
• Early clinical experience: Trials have tested placental and umbilical cord-derived MSCs, with acceptable safety reported in both studies.
• Promising, but still early: Visual acuity improved in four patients treated with placental MSCs, but larger, standardized studies are needed.

Reference:
Wang Y et al. Cell-based therapies for traumatic optic neuropathy: Recent advances, challenges, and perspectives. Neural Regen Res. 2026 May 1;21(5):1961-1980. https://pubmed.ncbi.nlm.nih.gov/40537004/

From Approval to Answers: What Comes Next for MSC Therapy in Acute GVHD?

THE FIRST FDA APPROVAL MARKS A TURNING POINT FOR MSC THERAPY IN ACUTE GVHD, BUT MIXED TRIAL RESULTS LEAVE IMPORTANT QUESTIONS UNANSWERED

Graft-versus-host disease (GVHD) can develop after a stem cell transplant when donor immune cells attack the patient’s tissues. It often affects the skin, liver, and digestive tract, and severe cases can become life-threatening. Steroids are the standard first treatment, but they do not work for everyone. MSCs may offer another way to calm harmful immune reactions without completely suppressing protective immunity. Rather than replacing damaged tissue, they release signals that reduce inflammation and reshape the immune response. Many infused MSCs become trapped in the lungs and are cleared by immune cells, which may trigger their anti-inflammatory effects. Remestemcel-L is now FDA-approved for children under 12 with steroid-refractory acute GVHD—a major milestone after two decades of research. Still, study results are mixed, products and manufacturing methods vary, and benefits may not last. Overall, MSCs may help selected patients, but standardized products, reliable potency tests, clearer patient selection, and robust trials are needed to define their role in GVHD care.

The FDA approval of remestemcel-L for children with steroid-refractory acute graft-versus-host disease (GVHD) marked a major milestone after two decades of work to bring mesenchymal stromal cell (MSC) therapy into clinical practice. The journey was far from straightforward. MSCs can come from different tissues and donors, patients vary biologically, manufacturing methods are not uniform, and clinical trials have often used different designs and endpoints. Together, these challenges show both the strong scientific interest in cell-based therapies and the difficulty of turning early promise into reliable clinical benefit.

Areez Shafqat and colleagues recently reviewed what comes next for MSC trials in acute GVHD in Cytotherapy. They traced the studies that shaped the field, examined why results have sometimes been difficult to compare, and outlined how future trials could become more rigorous, consistent, and clinically meaningful.

The story began in 2000, when MSCs first entered clinical trials to support blood-cell recovery in patients with breast cancer. In 2004, an MSC infusion induced remission in a patient with severe GVHD. Four years later, a European phase II study involving 55 patients with acute GVHD reported promising response rates. Regulatory progress followed: Japan approved JR-031 in 2013, and Germany authorized MSC-FFM under the hospital exemption pathway in 2018. In Australia, Cynata Therapeutics developed CYP001, an iPSC-derived MSC product. In a phase I trial for steroid-refractory acute GVHD, the 28-day overall response rate was 73.3%, and 100-day overall survival reached 86.7%; a randomized phase II trial is ongoing. In Asia, human umbilical cord-derived MSCs have produced promising but variable results, and China granted conditional approval to amimestrocel in 2025 after encouraging early-phase data.

Remestemcel-L remains the only FDA-approved MSC therapy and is indicated for children younger than 12 years with steroid-refractory acute GVHD. Early studies reported striking results, including a 94% overall response rate at day 28. However, later phase III trials did not confirm a durable clinical benefit. Overall, MSCs continue to show promising activity, especially in gastrointestinal GVHD, but available studies have not established a consistent advantage over other treatment options, including corticosteroids and ruxolitinib.

How MSCs work in GVHD is also more complex than researchers first expected. Rather than travelling directly to damaged tissues, most MSCs given intravenously become trapped in the lungs. There, the cells undergo apoptosis and are cleared by phagocytes. This process appears to trigger the anti-inflammatory and immune-regulating responses that may drive their therapeutic effect in acute GVHD.

The take-home message is cautiously optimistic. MSC therapy may help some patients with acute GVHD, but the field still faces major hurdles: products differ, the cells persist only briefly, their mechanisms are not fully understood, and trial results remain inconsistent. Standardized manufacturing, better potency testing, more precise patient selection, and robust clinical trials will be essential to define where MSCs truly fit in GVHD treatment.

Key points

• A major regulatory milestone: Remestemcel-L is the first FDA-approved MSC therapy, indicated for children under 12 with steroid-refractory acute GVHD.
• Promising, but mixed results: MSCs show encouraging activity, especially in gastrointestinal GVHD, but later trials have not confirmed a consistent, durable advantage over established treatments.
• The next challenge: Standardized manufacturing, better potency tests, careful patient selection, and robust trials are needed to define where MSCs fit in GVHD care.

Reference:
Shafqat A et al. The future of clinical trials of mesenchymal stromal cells in acute graft-versus-host disease. Cytotherapy. 2026;28(10):102886. Published online April 13, 2026. https://www.isct-cytotherapy.org/action/showPdf?pii=S1465-3249%2826%2900847-9

Nature’s Eye Dressing: How Amniotic Membrane Supports Healing and Repair

A NATURAL BIOLOGICAL DRESSING FOR THE OCULAR SURFACE HELPING CALM INFLAMMATION, LIMIT SCARRING, AND SUPPORT HEALING AFTER INJURY

A tissue from the placenta helping the eye heal? That is exactly what the amniotic membrane can do. This thin inner layer of the placenta acts like a natural biological dressing: it protects the eye’s surface, calms inflammation, limits scarring, and creates better conditions for repair. Its strongest track record is in rebuilding the ocular surface and treating moderate eye burns early, when controlling inflammation can make a real difference. Safety starts long before the membrane reaches the patient—donors must be carefully screened, and the tissue must be processed and preserved using validated methods. The clinical experience is encouraging, but products still vary and evidence is stronger for some eye conditions than others. The take-home message: amniotic membrane is a valuable ophthalmic tool, but wider use will depend on better standardization and further research.

The amniotic membrane (amnion) is the innermost layer of the placenta, lining the amniotic sac. It is a thin, translucent, avascular membrane composed of a single epithelial layer, basement membrane, and underlying mesenchymal stroma. Lacking blood vessels, nerves, muscles, and lymphatics, it relies on diffusion for nutrient and gas exchange during gestation and provides structural and protective support to the developing fetus.

In 2026 Ashraf M et al. published a comprehensive review that covers the history, properties, and clinical applications of amniotic membrane in ophthalmology.

Amniotic membrane is increasingly used in modern ophthalmology, with the strongest clinical support for ocular surface reconstruction and more exploratory applications in oculoplastics, glaucoma, and vitreoretinal surgery. Unlike many alternatives, amniotic membrane is readily available in large graft sizes and quantities. Its semi-transparent nature facilitates visualization of underlying structures during and after placement, supporting surgical precision and cosmetic outcomes. Amniotic membrane also provides a smooth, uniform surface that is well suited for covering ocular defects and promoting re-epithelialization, while being non-immunogenic.

The therapeutic functions of amniotic membrane are based on its anti-inflammatory and anti-scarring properties, modulation of angiogenesis, and ability to facilitate wound healing and tissue regeneration, mediated by numerous cytokines it releases. Amniotic membrane also exhibits antimicrobial activity mediated by antimicrobial peptides expressed or retained within the membrane, including human β-defensins, elafin, secretory leukocyte protease inhibitor, and cathelicidin LL-37.

In accordance with the United States Public Health Service (USPHS) Recommendations and FDA Regulations and Guidance for Human Cells, Tissues, and Cellular and Tissue-Based Products (HCT/Ps), donor eligibility for amniotic membrane is determined through a combination of medical record review and laboratory testing for communicable diseases. The use of fresh amniotic membrane is contraindicated due to the elevated risk of transmitting infectious diseases during the serological diagnostic window period. The two primary approaches to amniotic membrane preservation are cryopreservation and dry-storage techniques, each offering distinct advantages and limitations.

In modern ophthalmology, amniotic membrane is a valuable adjunct in the acute management of ocular burns and immune-mediated ocular emergencies, including Stevens–Johnson syndrome/toxic epidermal necrolysis. It is also used or being investigated in ocular manifestations of graft-versus-host disease (GVHD), limbal stem cell deficiency, fornix reconstruction and symblepharon management, corneal thinning and perforation, and glaucoma drainage device surgery.

In ocular burns, amniotic membrane functions as a biological dressing that provides surface protection and modulates inflammation during the critical early healing phase. Two randomized controlled trials involving 128 patients demonstrated improved healing and visual outcomes in Roper-Hall grade II–III burns with cryopreserved amniotic membrane, although no significant benefit was observed in grade IV injuries. Alternative and emerging amniotic membrane preparations include amniotic membrane extract eye drops, which have recently emerged as an innovative, non-surgical adjunctive biological therapy for ocular surface disease.

Despite its established clinical benefits, amniotic membrane preparations remain limited by biological variability, challenges in processing and standardization, clinical constraints, and limited evidence and access, highlighting the need for improved standardization and further research to optimize their therapeutic potential.

Key points

• A natural biological dressing: Amniotic membrane protects the ocular surface, reduces inflammation and scarring, and supports wound healing.
• Strongest evidence on the eye surface: Its best-established role is in ocular surface reconstruction and the early treatment of moderate ocular burns.
• Safety starts with processing: Donor screening and validated preservation are essential; fresh membrane is avoided because of infection-transmission risk.
• Promising, but not fully standardized: Wider use will require more consistent products, stronger evidence, and better access to treatment.

Reference:
Ashraf M et al. Amniotic membrane in ophthalmology: Historical perspectives, biological properties, and clinical applications. Prog Retin Eye Res. 2026 Jul;113:101473. https://www.sciencedirect.com/science/article/pii/S135094622600039X?via%3Dihub

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