# Cell-based therapies have disease-modifying effects on osteoarthritis in animal models: A systematic review by the ESSKA Orthobiologic Initiative. Part 3: Umbilical cord, placenta, and other sources for cell-based injectable therapies

Yosef Sourugeon, Angelo Boffa, Carlotta Perucca Orfei, Laura de Girolamo, Jérémy Magalon, Mikel Sánchez, Thomas Tischer, Giuseppe Filardo, Lior Laver

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Yosef Sourugeon, Angelo Boffa, Carlotta Perucca Orfei, Laura de Girolamo, Jérémy Magalon, et al. Cell-based therapies have disease-modifying effects on osteoarthritis in animal models: A systematic review by the ESSKA Orthobiologic Initiative. Part 3: Umbilical cord, placenta, and other sources for cell-based injectable therapies. Knee Surgery, Sports Traumatology, Arthroscopy, 2025, 33 (5), pp.1695-1708. 10.1002/ksa.12472. hal-04948786

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# Cell-based therapies have disease-modifying effects on osteoarthritis in animal models: A systematic review by the ESSKA Orthobiologic Initiative. Part 3: Umbilical cord, placenta, and other sources for cell-based injectable therapies

Yosef Sourugeon¹ ID

Angelo Boffa²,³

Carlotta Perucca Orfei⁴ ID

Laura de Girolamo⁴

Jeremy Magalon⁵,⁶,⁷

Mikel Sánchez⁸,⁹

Thomas Tischer¹⁰,¹¹

Giuseppe Filardo²,¹²,¹³

Lior Laver¹⁴,¹⁵,¹⁶

## Correspondence

Yosef Sourugeon, Chaim Sheba Medical Centre, Division of Surgery, Orthopaedics Department, Israel - Writing, Investigation. Email: yossi2k10@gmail.com

## Funding information

None

## Abstract

**Purpose:** This systematic review aimed to investigate in animal models the presence of disease-modifying effects driven by non-bone marrow-derived and non-adipose-derived products, with a particular focus on umbilical cord and placenta-derived cell-based therapies for the intra-articular injective treatment of osteoarthritis (OA).

**Methods:** A systematic review was performed on three electronic databases (PubMed, Web of Science and Embase) according to PRISMA guidelines. The results were synthesised to investigate disease-modifying effects in preclinical animal studies comparing injectable umbilical cord, placenta, and other sources-derived products with OA controls. The risk of bias was assessed using the SYRCLE tool.

**Results:** A total of 80 studies were included (2314 animals). Cell therapies were most commonly obtained from the umbilical cord in 33 studies and placenta/amniotic tissue in 18. Cell products were xenogeneic in 61 studies and allogeneic in the remaining 19 studies. Overall, 25/27 (92.6%) of studies on umbilical cord-derived products documented better results compared to OA controls in at least one of the following outcomes: macroscopic, histological and/or immunohistochemical findings, with 19/22 of studies (83.4%) show positive results at the cartilage level and 4/6 of studies (66.7%) at the synovial level. Placenta-derived injectable products documented positive

For affiliations refer to page 10.

**Abbreviations:** ADAMTS5, A disintegrin and metalloproteinase with thrombospondin motifs 5; ASA, amniotic suspension allograft; BMAC, bone marrow aspirate concentrate; CTXII, C-terminal telopeptide of type II collagen; EVs, extracellular vesicles; ICAM-1, intercellular adhesion molecule 1; IHC, immunohistochemistry; IL-1β, interleukin 1 beta; iPSCs, induced pluripotent stem cells; micro-CT, micro-computed tomography; MMP13, matrix metallopeptidase 13; MRI, magnetic resonance imaging; MSC, mesenchymal stromal cells; NO, nitric oxide; OA, osteoarthritis; PGE2, prostaglandin E2; PRISMA, Preferred Reporting Items for Systematic Reviews and Meta-Analyses; PRP, platelet-rich plasma; SVF, stromal vascular fraction; SYRCLE, Systematic Review Centre for Laboratory Animal Experimentation; TGFβ, transforming growth factor beta; TNFα, tumour necrosis factor alpha; UC-MSC, umbilical cord mesenchymal stromal cells.

[Correction added on 19 October 2024, after first online publication: Affiliations for co-authors Laura de Girolamo and Jeremy Magalon have been updated.]

This is an open access article under the terms of the [Creative Commons Attribution License](https://creativecommons.org/licenses/by/4.0/), which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

© 2024 The Author(s). *Knee Surgery, Sports Traumatology, Arthroscopy* published by John Wiley & Sons Ltd on behalf of European Society of Sports Traumatology, Knee Surgery and Arthroscopy.
results in 13/16 (81.3%) of the studies, 12/15 (80.0%) at the cartilage level, and 2/4 (50.0%) at the synovial level, but 2/16 studies (12.5%) found overall worse results than OA controls. Other sources (embryonic, synovial, peripheral blood, dental pulp, cartilage, meniscus and muscle-derived products) were investigated in fewer preclinical studies. The risk of bias was low in 42% of items, unclear in 49%, and high in 9% of items.

**Conclusion:** Interest in cell-based injectable therapies for OA treatment is soaring, particularly for alternatives to bone marrow and adipose tissue. While expanded umbilical cord mesenchymal stem cells reported auspicious disease-modifying effects in preventing OA progression in animal models, placenta/amniotic tissue also reported deleterious effects on OA joints. Lower evidence has been found for other cellular sources such as embryonic, synovial, peripheral blood, dental-pulp, cartilage, meniscus, and muscle-derived products.

**Level of Evidence:** Level II.

KEYWORDS

cartilage, mesenchymal stromal cells (MSCs), placenta, stem cells, synovial, umbilical cord

INTRODUCTION

Osteoarthritis (OA) is the most common form of joint degenerative disease and one of the major causes of pain and disability in older adults, affecting around 3.6% of the population globally with a heavy burden on healthcare systems [10, 32]. Current non-operative treatment paradigms are focused on symptom relief, with benefits often of limited duration, rather than providing disease-modifying effects and changing the OA course. The limitations of these treatments in addressing altered tissue homoeostasis in OA have led to an increasing interest in orthobiologic strategies. Relying on their regenerative and immuno-modulating properties through cellular mechanisms or blood-derived proteins, they have been suggested to have the potential to restore homoeostasis in many tissues, including cartilage and overall joint tissues [12]. Recently, the European Society of Sports Traumatology, Knee Surgery and Arthroscopy (ESSKA) Orthobiologic Initiative (ORBIT) underlined OA disease-modification properties in animal models for orthobiologic agents such as platelet-rich plasma (PRP) [9] and mesenchymal stromal cells (MSCs) from adipose tissue [56] and bone marrow [8].

Given their therapeutic properties, MSCs have been suggested to be suitable candidates for treating damaged tissues. These cells are found in most vascularises tissues, especially in adipose tissue and bone marrow, although other sources have also been suggested. The current review will focus on other tissue sources for MSCs, including foetal annexes (i.e., placenta and amnion), synovial tissue, blood-derived, muscle-derived, and induced pluripotent stem cells (iPSCs). Compared to bone marrow and adipose tissue, these sources are more challenging to obtain due

to procedural complexity, regulatory and ethical issues, lower MSC yield, or the need for lab manipulation [3]. Despite the source, abundant literature showed that MSCs exert an anti-inflammatory effect on chondrocytes and synoviocytes and modulate the immune system response towards an anti-inflammatory phenotype. In this light, the MSCs from various sources may affect the cartilage tissue of OA patients in two ways: (1) counteract the inflammatory processes in the cartilage tissue; (2) induce a chondrogenic response in the cartilage tissue. The culminating effect of these two processes may lead to a disease-modifying effect on the affected joint [55, 70]. Transcriptional and epigenetic analysis of different MSC populations has been shown to have striking similarities [7]. However, not all MSCs are the same, as the cells' efficacy might also be source-dependent [65]. The difference lies in the expressed growth factors or active pathways between the various MSC sources, which may affect the chondrogenic potential of each cell source and the required conditions required for such a process, thus underlining the importance of exploring the potential of the different sources when applied to address OA processes [7].

This systematic review, Part 3 of a series of publications by the ESSKA ORBIT on cell-based products for OA treatment, aimed to investigate in animal models the presence of disease-modifying effects driven by non-bone marrow-derived and non-adipose-derived products, with a particular focus on umbilical cord and placenta-derived cell-based therapies for the intraarticular injective treatment of OA. This study hypothesises that cell-based injectable therapies derived from umbilical cord and placental tissues will exhibit significant disease-modifying effects on osteoarthritis in animal models.
# MATERIALS AND METHODS

## Search strategy and article selection

A systematic review of the literature was conducted on three electronic databases (PubMed, Web of Science, and Embase) according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The methodology of this systematic review, divided into three articles (according to different MSCs sources), was already reported in previous publications [8, 56]. Two authors (CP and YS) conducted the screening process and analysis, and a third author (AB) was involved in resolving any discrepancies. Preclinical studies focusing on the intra-articular use of MSCs to address joints affected by OA were included based on the following inclusion criteria: Animal studies, articles written in English, purely injective treatments for cartilage degeneration and OA. Exclusion criteria were: In vitro or clinical studies, congress abstracts, reviews, articles written in other languages than English, studies on joint diseases different from OA, studies analysing associated surgery, studies on the use of MSC secretome/extracellular vesicles, and studies reporting the use of MSCs without a control group or the combined use of MSCs with another product without analysing the specific contribution of MSCs application.

While the first two articles of this ORBIT series analysed the disease-modifying effects of adipose tissue-derived products and bone marrow-derived products, respectively [8, 56], the current manuscript focuses on other remaining MSC sources. The flow-chart reported in Figure 1 graphically describes the systematic review process updated on 1 July 2023 for this third party using the same string: (MSC OR mesenchymal cell OR stem cell OR stromal cell OR progenitor cell OR bone marrow concentrate OR bone marrow aspirate concentrate OR BMAC OR micro-fra* adipose tissue OR microfra* adipose tissue OR stromal vascular fraction OR SVF OR amniotic suspension allograft OR ASA OR placenta* OR umbilical cord OR amnio*) AND (osteoarthritis).

## Data extraction and quality assessment

Relevant data were extracted from article texts, tables, and figures and then collected in a database to be analysed for the purpose of the present study. In detail, the following data were collected: authors, journal, year of publication, number and type of evaluated animals, joint involved, OA model, type of treatment, follow-up, results, and cell product characteristics, including source, origin, MSC count, additional procedures, processing modality

<figure><img src="image_2.png" /><figcaption>FIGURE 1 PRISMA flowchart of the study selection process. EVs, extracellular vesicles, OA, osteoarthritis.</figcaption></figure>
(expanded versus “point-of-care”), and injective protocol. A synthesis of the obtained results was performed, analysing the clinical and imaging findings as well as the disease-modifying effects on the OA process of the different preparations. The effects provided by the cell-based injectable therapies were considered positive from a disease-modifying perspective when the study reported better objective results (with a statistical significance) for cell therapies compared to OA controls in at least one of the following outcomes: macroscopic, histological, and/or immunohistochemical findings. In particular, the analysis was based on comparing the experimental groups versus the respective controls (vehicle injection or no treatment). The risk of bias assessment of the included studies was performed using the Systematic Review Centre for Laboratory Animal Experimentation (SYRCLE)'s tool [33].

## RESULTS

### Study selection and analysis

Out of 4732 titles initially identified, 80 studies met the inclusion criteria after screening (Figure 1). These studies, which showed a significant increase in publications after 2018, focused primarily on cell therapies derived from umbilical cord and placental tissues. Small animal models, mainly rodents and rabbits, were most commonly used, with most studies evaluating the effects of expanded MSCs. The diversity in cell sources and the distribution of studies across different animal models are further detailed in Figures 1 and 2.

Sixty-seven studies evaluated the effects on small animal OA models (rodents: 55; rabbits: 12) while 13

studies focused on large animals (dogs: 4; horses: 3; sheep: 3; goats: 1; monkeys: 1; and pigs: 1). The number of assessed animals were reported in 75 studies, with a total of 2314 animals: 1831 rodents, 208 rabbits, 129 dogs, 59 sheep, 42 horses, 27 goats, 10 pigs, and 8 monkeys. The treated joint was the knee in most studies (74), the elbow in two studies, the metacarpophalangeal in two studies, the fetlock joint in one study, and the temporomandibular joint in one study. The OA model was surgically induced in 45 studies (mostly through ligament transection and/or meniscectomy), chemically induced in 29 studies (through the injection of pro-inflammatory or chondrotoxic products), or naturally occurring in six studies (veterinary clinical studies). Expanded MSCs were evaluated in 69 studies, while “point-of-care” products were analysed in 11 studies (all small animal studies). For expanded MSCs, the injected dose ranged from $3.0 \times 10^4$ to $1.8 \times 10^8$ cells for small animals and from $1.0 \times 10^6$ to $5.0 \times 10^7$ cells for large ones. Cell products were xenogeneic in 61 studies and allogeneic in the remaining 19 studies. The amount of the injected volume ranged from 25.0 µL to 4.0 mL in small animals and from 0.1 mL to 2.0 mL in large animals. The injective protocol consisted of a single injection in 52 studies, multiple injections (from 2 to 14) in 19 studies, seven studies compared different injective protocols, while two studies did not describe the injection schedule. The follow-up period of the included studies ranged from 2 weeks to 12 months following OA induction. Further details on the characteristics of the included studies are reported in Supporting Information: Table 1, while the following paragraphs describe the disease-modifying effects of cell therapies based on the cell source.

<figure><img src="image_3.png" /><figcaption>**FIGURE 2** Animal studies over the years on intra-articular injections of cell therapies different to adipose tissue and bone marrow to address OA. X axis, year of publication; Y axis, number of published articles.</figcaption></figure>
## Umbilical cord-derived injectable products

A total of 33 studies analysed the injective use of expanded umbilical cord MSCs (UC-MSCs) in animal OA joints. Out of these, 27 studies investigated their disease-modifying effects concerning OA controls (vehicle injections or untreated joints). Overall, 25/27 studies (92.6%) documented better results compared to OA controls in at least one of the following outcomes: macroscopic, histological, and/or immunohistochemical findings, while the remaining 2/27 studies (7.4%) reported no improvement from the injective treatment. In detail, overall better results in favour to UC-MSCs treatment were documented in 5/7 studies (71.4%) for macroscopic evaluations (gross morphological scores), in 19/23 studies (82.6%) for histological evaluations, and 12/12 studies (100.0%) for immunohistochemical analyses. A summary of UC-MSCs effects on OA joints is reported in Figure 3, while more specific details on their effects are reported in Table 1.

## Placental tissue-derived injectable products

The effects of placental tissue-derived injectable products on animal OA models were evaluated in 18 studies: 11 studies focused on “point of care” products, while seven studies focused on expanded MSCs. Out of these 18 studies, 16 investigated the disease-modifying effects of these products with respect to OA controls. Overall, 13/16 of studies (81.3%) documented better results compared to OA controls in at least one

of the following outcomes: macroscopic, histological, and/or immunohistochemical findings, one study (6.3%) reported no improvement from the injective treatment, while 2/16 studies (12.5%) found worse results than OA controls. In detail, overall better results were documented in 3/4 studies (75.0%) for macroscopic evaluations (gross morphological scores), in 11/14 studies (78.6%) for histological evaluations, and in 2/3 studies (66.7%) for immunohistochemical analyses. A summary of placental tissue-derived injectable products effects on OA joints is reported in Figure 4, while more specific details on their effects are reported in Table 2.

## Other cell sources

Disease-modifying effects induced by cell therapies obtained from the remaining sources have been analysed in less than 10 studies per source. Therefore, they are all described in this paragraph.

Eleven studies evaluated the injective use of expanded synovial fluid/membrane MSCs in animal OA joints, of which nine reported objective outcomes. In detail, 8/9 studies (88.9%) documented better results compared to OA controls in at least one of the following outcomes: macroscopic, histological, and/or immunohistochemical findings, while one study (11.1%) reported no improvement. Disease-modifying effects were documented at both cartilage and synovial membrane levels. Moreover, three studies conducted a biomarker evaluation, all reporting positive changes in inflammatory and catabolic markers compared to OA controls [22, 58, 75]. Three studies also evaluated imaging outcomes, finding

<figure><img src="image_4.png" /><figcaption>**FIGURE 3** Disease-modifying effects on OA joints induced by umbilical cord-derived products. The bar chart shows the percentage of studies that met the specific effects. Positive effects (green) vs. no effects (orange) in imaging findings (n = 8), clinical results (n = 7), biomarker evaluation (n = 10), macroscopic results (n = 7), histological results (n = 23), and immunohistochemical results (n = 12). IHC, immunohistochemistry; OA, osteoarthritis.</figcaption></figure>
<table><caption>TABLE 1 Disease-modifying (DM) effects of umbilical cord-derived injectable products.</caption><thead><tr><th></th><th>Results compared to OA controls</th><th>Details</th></tr></thead><tbody><tr><td>DM effects at cartilage level</td><td>19/22 studies (83.4%) → Positive results</td><td>Better articular surface, less cartilage fibrillation, higher chondrocyte count, upregulation of aggrecan and type 2 collagen, and lower staining of IL-1β, TNFα, MMP13, and ADAMTS5 compared to OA controls [6, 27, 37, 51, 68, 71, 84].</td></tr><tr><td>DM effects at synovial level</td><td>4/6 studies (66.7%) → Positive results</td><td>Lower inflammatory cell infiltration and hyperplasia compared to OA controls [15, 34, 71].</td></tr><tr><td>Effects on OA biomarkers</td><td>9/10 studies (90.0%) → Positive results</td><td>Higher serum levels of IL-10 and synovial fluid levels of TGFβ. Lower serum levels of IL-6, TNFα, and NO, and synovial fluid levels of IL-1β, IL-6, TNFα, and MMP13 [21, 45, 83, 84].</td></tr><tr><td>Clinical effects</td><td>6/7 studies (85.7%) → Positive results</td><td>Higher peak vertical force, better thermal withdrawal latency, better paw withdrawal threshold, and lower lameness [38, 39, 80, 85].</td></tr><tr><td>Imaging findings</td><td>7/8 studies (87.5%) → Positive results</td><td>Micro-CT analysis (positive results in 5/5 studies): lower grade of OA change, larger joint space, and higher trabecular thickness and bone volume fraction [14, 15, 34, 53, 77]. Radiographic evaluation (positive results in 2/3 studies): less osteophyte formation and joint narrowing after UC-MSCs treatment [4, 38, 77]. MRI (positive results in 1/2 studies): better cartilage thickness and volume [4, 83]. Ultrasonographic evaluation: one study not reporting benefits [4].</td></tr></tbody></table>

Abbreviations: ADAMTS5, a disintegrin and metalloproteinase with thrombospondin motifs 5; IL, interleukin; Micro-CT, micro-computed tomography; MMP13, matrix metallopeptidase 13; MRI, magnetic resonance imaging; NO, nitric oxide; OA, osteoarthritis; TGFβ, transforming growth factor beta; TNF-α, tumour necrosis factor-α; UC-MSC, umbilical cord mesenchymal stromal cells.

<figure><img src="image_5.png" /><figcaption>FIGURE 4 Disease-modifying effects on OA joints induced by placental tissue-derived injectable products. The bar chart shows the percentage of studies that met the specific effects. Positive effects (green) vs. no effects (orange) vs. negative effects (red) in imaging findings (n = 4), clinical results (n = 6), biomarker evaluation (n = 10), macroscopic results (n = 4), histological results (n = 14) and immunohistochemical results (n = 3). IHC, immunohistochemistry; OA, osteoarthritis.</figcaption></figure>

positive results after the injections in two studies (MRI and radiograph analyses) and no benefits in one study (MRI analysis) [31, 40, 81]. Finally, no studies assessed clinical outcomes after synovial fluid/membrane-derived cell products.

Four studies evaluated the injective use of expanded peripheral blood MSCs in animal OA joints, of which only two reported objective outcomes: both studies documented better results compared to OA controls in terms of macroscopic, histological, and immunohistochemical

findings [11, 44]. The same two studies documented positive changes in terms of serum and synovial fluid biomarker levels [11, 44]. Regarding imaging evaluations, one study reported positive findings at the subchondral level at micro-CT analysis, while one study did not find any benefits at radiographic evaluation [11, 44]. Regarding clinical assessment, one study reported better clinical scores in OA animals treated with peripheral blood MSCs injections, while one study did not find any clinical benefits [11, 17].
<table><caption>TABLE 2 Disease-modifying (DM) effects of placental tissue-derived injectable products.</caption><thead><tr><th></th><th>Results compared to OA controls</th><th>Details</th></tr></thead><tbody><tr><td>DM effects at cartilage level</td><td>12/15 studies (80.0%) →<br>Positive results</td><td>Lower cartilage degeneration and articular fibrillation, higher staining of type 2 collagen and Sox-9, and lower staining of MMP13, ADAMT4, and ADAMT5 [23, 26, 48, 66].</td></tr><tr><td>DM effects at synovial level</td><td>2/4 studies (50.0%) →<br>Positive results</td><td>Better synovitis scores [47,77].</td></tr><tr><td>Effects on OA biomarkers</td><td>6/6 studies (100.0%) →<br>Positive results</td><td>Higher serum levels of IL-4, IL-10, and TIMP-1, and synovial fluid levels of IL-2 and IL-10. Lower serum levels of IL-1β, IL-6, TNFα, ICAM-1, leptin, and selectin, and synovial fluid levels of IL-1β, IL-6, CTXII, TNFα, and PGE2 [5, 41, 42, 73, 73].</td></tr><tr><td>Clinical effects</td><td>4/4 studies (100.0%) →<br>Positive results</td><td>Better clinical outcomes in terms of pain threshold levels, joint swelling, and weight-bearing differences [5, 26, 41, 42].</td></tr><tr><td>Imaging findings</td><td>2/4 studies (50.0%) →<br>Positive results</td><td>Micro-CT analysis (positive results in 2/4 studies): greater articular cartilage thickness and volume. Negative results in one study reporting higher cartilage surface roughness and osteophyte cartilage thickness [41, 59, 63, 78].</td></tr></tbody></table>

Abbreviations: ADAMTS, a disintegrin and metalloproteinase with thrombospondin motifs; CTXII, C-terminal telopeptide of type II collagen; ICAM-1, intercellular adhesion molecule 1; IL, interleukin; Micro-CT, micro-computed tomography; MMP13, matrix metallopeptidase 13; OA, osteoarthritis; PGE2, prostaglandin E2; TNF-α, tumour necrosis factor-α.

Three studies evaluated the injective use of expanded cartilage-derived MSCs in animal OA joints. All these studies documented better results compared to OA controls in terms of histological and immunohistochemical findings at cartilage levels [18, 24, 79]. One of these studies also detected positive changes in the biomarkers profile compared to OA controls [24].

Three studies evaluated the injective use of expanded muscle-derived MSCs in animal OA joints. Two of these studies documented better results compared to OA controls in terms of histological and immunohistochemical findings at the cartilage level, while the third study did not find any benefit [13, 49, 50]. One of these studies also detected positive changes in the biomarker profile compared to OA controls [13].

The remaining studies, focusing on expanded MSCs derived from meniscus (two studies), embryonic tissue (one study), epidermidis (one study), and dental pulp (one study), also reported overall positive disease-modifying effects. Supporting Information: Table 1 provides further details on the characteristics of these studies.

## Risk of bias assessment

The SYRCLE's risk of bias tool assessment of the included studies found an 84% agreement between the two authors involved in the evaluation. 42% of items were rated as low risk of bias, 9% of items were rated as high risk of bias, and 49% of items were rated as unclear. The analysis of the risk of bias over time did not display a significant trend toward improving the quality of the included studies, with low-risk items reported in 42% versus 41% in the most recent half of the

papers vs. the older ones. The risk of bias assessment of all included studies is illustrated in Figure 5.

## DISCUSSION

The main finding of this systematic review of preclinical studies is that there is an increasing interest in the use of cell-based injectable therapies for OA treatment alternative to the most common bone marrow and adipose tissue sources, with stronger evidence on cell therapies obtained from the umbilical cord and placenta/amniotic tissue. While expanded umbilical cord, MSCs reported promising disease-modifying effects in preventing OA progression in animal models, placenta/amniotic tissue also reported negative effects on OA joints. Lower evidence has been found for other cellular sources such as embryonic, synovial, peripheral blood, dental-pulp, cartilage, meniscus, and muscle-derived products.

Over the past decade, growing interest in the clinical use of MSCs has led to exploring various sources. While bone marrow and adipose tissue are the most common due to their ease of extraction and beneficial properties, other MSC sources like umbilical cord blood, dental pulp, amniotic fluid, and placenta-derived MSCs have also shown promise. These alternatives offer advantages like higher proliferative capacity, excellent regenerative potential, low immunogenicity, and non-invasive collection [30, 43, 47, 52, 57]. However, comparative studies comparing different sources of MSCs showed contradictory results [1, 35, 36, 62]. Moreover, current evidence is limited to in vitro studies, which do not necessarily directly translate into effects
<figure><img src="image_6.png" /><figcaption>**FIGURE 5** SYRCLE's risk of bias tool assessment of the included studies. The bar chart shows the percentage of all studies that met each quality item, scored as “Low risk”, “High risk”, or “Unclear”.</figcaption></figure>

at the joint level. This systematic review evaluated the disease-modifying effects of these treatments in animal studies to provide objective evidence and support their clinical use.

Different sources of MSCs have been explored, but a synthesis of the disease-modifying effects could only be carried out for umbilical cord, placenta, and synovial fluid-derived MSCs. Umbilical cord-derived injectable products have been the most investigated in animal studies, showing a 92.6% rate of positive disease-modifying effects, with 83.4% of the studies reporting benefits at the cartilage level. These benefits have been observed through macroscopic, histological, and immunohistochemical analysis, reported in 71.4%, 82.6%, and 100% of cases, respectively. Similarly, expanded synovial fluid/membrane cells showed positive results, with 88.9% of the studies reporting a reduction of OA progression at macroscopic, histological, and immunohistochemical levels. On the other hand, placenta-derived products have demonstrated some conflicting results. On one side, there were positive disease-modifying effects, with 80% of the studies reporting benefits at the cartilage level. These benefits have been observed through macroscopic, histological, and immunohistochemical analysis, showing positive disease-modifying effects in 75%, 78.6%, and 66% of the cases, respectively. On the other side, placenta-derived products also led to some negative effects on OA joints, with an increase in synovitis and fibrosis after ASA injections, as documented in two studies [41, 42]. Looking at these results, greater attention must be paid to the clinical translation for placental-derived products. Unfortunately, despite some promising results, evidence on the other cell sources is still scarce. Thus, further investigation into their clinical potential is warranted.

Imaging analysis, from simple radiography to MRI, showed more consistent results with UC-MSCs, with seven out of eight studies reporting a positive effect compared to OA controls (micro-CT in five studies, plain radiographs in three studies, and MRI in two studies). For placenta-derived products, results were less consistent, with two out of four studies (Micro-CT) reporting positive effects, one study reporting no significant changes, and one study reporting a worsening. Concerning the findings derived from histological and immunohistochemical analyses, these evaluations should be considered with more caution due to the limits of the imaging analyses in detecting cartilage and subchondral bone level changes, as previously documented in the previous ESSKA-ORBIT studies [4, 18] as well as in clinical practice, where there is poor correlation between clinical outcome and imaging findings [79].

The comparison of the results of the current study with those obtained by the previous ESSKA-ORBIT systematic reviews on adipose and bone-marrow-derived products showed that umbilical-cord-derived products reported similar disease-modifying effects compared to adipose-derived products and better than bone-marrow products, although supported by a lower number of studies. In contrast, placenta-derived products yielded inferior disease-modifying effects to these treatments. More precisely, overall disease-modifying effects were found in 94% of studies on adipose-derived products, 93% for umbilical cord products, 85% for bone marrow, and 81% for placenta-derived products. Interestingly, umbilical cord and placenta-derived products showed better clinical performance, with 86% and 100% of papers reporting a significant improvement in treated animals versus 78% in both adipose and bone marrow groups, respectively. This may be
due to the limited number of studies. Also, it may be speculated to be related to a better overall inflammatory response, reflected by an improved biomarker secretion profile reported in 100% and 90% of the placenta and umbilical cord-derived products, respectively, versus 86% and 50% in adipose and bone-marrow-derived products, respectively. Finally, while over 80% of the included studies found improvement at the cartilage level, only 67% and 50% found the same effects on the synovium tissue in the umbilical cord and placenta-derived products, respectively. These results are comparable to those reported in adipose-derived products (60%) and superior to bone-marrow products (30%).

Umbilical cord and placenta-derived products have been a focus of interest for researchers, clinicians, and patients for years. These cell-based products have a lower occurrence of replicative senescence, a higher proliferation rate than other MSC sources, robust immunomodulatory qualities, and are relatively easy to produce and readily available [29, 72, 74]. They also provide a solution for those who cannot have autologous tissue harvested due to contraindications or those who wish to avoid the harvesting procedure. Therefore, they seem ideal candidate sources for treating OA. This systematic review confirms that regenerative properties seen in in vitro studies in umbilical cord and placenta-derived MSCs were translated into improved structural and clinical outcomes in animal models. Most of the immunomodulatory response was seen at the cartilage level and indirectly at the serum and synovial fluid levels. However, the current study's findings and previous studies in this series showed that MSCs from different sources had less effect on synovium [8, 56]. It has been demonstrated that MSCs show immunomodulatory activity in co-culture studies, reducing inflammation and apoptosis. Still, this effect was not as pronounced in animal studies included in the previous ESSKA-ORBIT reviews and the current study [8, 56, 82]. The dosage and timing of MSC injections could be key factors influencing the outcomes. The quantity of cells administered may have been optimal for cartilage while insufficient for producing a significant impact on the synovium, which suffers more from inflammatory infiltration and thus is more difficult to influence by treatments that rely on mechanisms of action directed against inflammation. It has been hypothesised that synovitis, especially at the early stages of OA, mediates OA structural and clinical OA progression [2, 54, 64]. However, studies that examined direct inhibition of inflammatory mediators such as IL-1β, IL-6, and TNFα found that they did not improve pain, synovitis, or OA progressions as assessed by MRI or ultrasound [16, 67, 69]. This ESSKA-ORBIT review suggests that most clinical and structural positive effects could result from cartilage anabolic and anti-inflammatory effects rather than a product of

synovial tissue response. Regardless, only a handful of papers have examined the synovial effect of intraarticular MSC injection. R. Ferracini et al. investigated preclinical conditions in patients that may affect clinical outcomes following MSC treatment. They found that patients with predominant synovitis are prone to persistent pain 1-year post-treatment [25]. These results underscore the complexity of OA pathomechanism and potential therapies. Further research should be conducted on the role of synovium on OA progression in the different stages of the disease and its role in the response to cell-based therapies.

Most of our knowledge of umbilical cord and placenta-derived products stems from preclinical in vitro and animal studies. Results as objective as those reported in animals are difficult to reproduce in humans due to various ethical and practical concerns. In contrast, clinical outcomes are more difficult to assess in animal studies. Dhillon et al. [19] conducted a systematic review examining the clinical efficacy of umbilical cord-derived products in treating OA. Overall, seven studies were included. They found umbilical cord-derived products yielded clinical improvement in patients, but the literature lacks high-quality randomised studies [19]. A recent systematic review by Di Matteo et al. [20] included 16 clinical studies on placenta-derived products. The authors concluded that these products show a good safety profile and satisfactory results in treating OA. Another potential clinical use may be in the augmentation of surgical procedures. In patients with OA with axial deformity, a high tibial osteotomy (HTO) may be indicated. HRB Abd Razak et al. conducted a systematic review examining the efficacy of adipose and umbilical cord-derived MSC therapy for early OA combined with HTO. They reviewed nine articles and reported good short-term clinical results [60]. Similarly, Reale et al. [61] examined a broader spectrum of cartilage surgical treatments combined with cellular injective treatments. They found that injective treatments enhance pain relief and functional recovery in these patients [61]. However, the aforementioned clinical studies are heterogeneous in their preparation process and need more high-quality evidence [20].

The current systematic review has several limitations. Firstly, the included papers exhibit heterogeneity across various aspects, including diverse methodologies employed for OA induction, differences in follow-up periods and measurement criteria, various injection formulations and protocols, and the use of different animal models. The heterogeneous nature of the studies included may be explained by the relative novelty of MSC application in OA and the lack of clear treatment protocols and recommendations. Methodological heterogeneity can be improved by adherence to specific guidelines, that is, SYRCLE's tool. Addressing methodological heterogeneity alone can enhance the quality and reliability of results. Secondly, the prevalent
utilisation of xenograft products, particularly those derived from umbilical and placental sources, raises concerns regarding potential immune responses and rejection in the treated animals, compromising effectiveness. Unlike allo- and auto-grafts, the regenerative potential of xenografts is unclear, especially in humans. Furthermore, MSCs are commonly sourced from autografts and allografts in the clinical setting. Consequently, the translatability of the observed results to the clinical domain remains uncertain. Thirdly, in most cases, animal models did not follow the pathophysiology of OA development in humans, as it was mostly induced using chemical or mechanical methods. However, while different in physiology and composition, animal models allow us to examine the modulatory effects of MSCs on impaired cartilage in ways that are challenging in human trials (i.e., histological examination). It is essential, as MR imaging and radiographic evaluations, the most commonly used imaging evaluation tools in human trials, proved less reliable in assessing the effect of MSC treatment on cartilage tissue. In this light, preclinical studies remain important to understand how MSCs target and affect joint tissues affected by OA processes, giving useful indications for translating these cell-based approaches into clinical practice [28]. Lastly, in their scoping review, Liu et al. [46] emphasised the lack of standardisation in MSC preparation devices and cellular characterisation, highlighting the need for improved reporting and standardised protocols in future studies.

## CONCLUSIONS

There is an increasing interest in using cell-based injectable therapies for OA treatment alternative to the most common bone marrow and adipose tissue sources, with higher evidence on cell therapies obtained from umbilical cord and placenta/amniotic tissue. While expanded umbilical cord, MSCs reported promising disease-modifying effects in preventing OA progression in animal models, placenta/amniotic tissue also reported deleterious effects on OA joints. Lower evidence has been found for other cellular sources such as embryonic, synovial, peripheral blood, dental pulp, cartilage, meniscus, and muscle-derived products.

## AUTHOR CONTRIBUTIONS

**Yosef Sourugeon:** Writing; investigation. **Angelo Boffa:** Investigation; formal analysis; resources.

**Carlotta Perucca Orfei:** Investigation. **Laura de Girolamo:** Conceptualization; review & editing; methodology.

**Jeremy Magalon:** Review & editing. **Mikel Sánchez:** Review & editing. **Thomas Tischer:** Conceptualization; review & editing. **Giuseppe Filardo:** Project administration. **Lior Laver:** Supervision.

## AFFILIATIONS

## ACKNOWLEDGMENTS

Authors LDG, GF, LL, JM, MS, and TT are members of the Orthobiologics Initiative (ORBIT) of the European Society of Sports Traumatology, Knee Surgery & Arthroscopy (ESSKA).

## CONFLICT OF INTEREST STATEMENT

The authors declare no conflicts of interest.

## DATA AVAILABILITY STATEMENT

Data supporting this study are included within Supporting Information (Table 1).

## ETHICS STATEMENT

This material is the authors' own original work, which has not been previously published elsewhere. The paper is not currently being considered for publication elsewhere. The paper reflects the authors' own research and analysis in a truthful and complete manner. The paper properly credits the meaningful contributions of co-authors and co-researchers. The results are appropriately placed in the context of prior and existing research. All sources used are properly disclosed (correct citation). Literally copying of text must be indicated as such by using quotation marks and giving proper reference. All authors have been personally and actively involved in substantial work

<footnote n="1">¹Division of Surgery, Orthopaedics Department, Chaim Sheba Medical Centre, Ramat Gan, Israel</footnote>

<footnote n="2">²Applied and Translational Research Center, IRCCS Istituto Ortopedico Rizzoli, Bologna, Italy</footnote>

<footnote n="3">³Clinica Ortopedica e Traumatologica 2, IRCCS Istituto Ortopedico Rizzoli, Bologna, Italy</footnote>

<footnote n="4">⁴Laboratorio di Biotecnologie Applicate all'Ortopedia, IRCCS Ospedale Galeazzi Sant'Ambrogio, Milan, Italy</footnote>

<footnote n="5">⁵INSERM, NRA, C2VN, Aix Marseille University, Marseille, France</footnote>

<footnote n="6">⁶SAS Remedex, Marseille, France</footnote>

<footnote n="7">⁷Cell Therapy Laboratory, Hôpital De La Conception, AP-HM, Marseille, France</footnote>

<footnote n="8">⁸Advanced Biological Therapy Unit, Hospital Vithas Vitoria, Vitoria-Gasteiz, Spain</footnote>

<footnote n="9">⁹Arthroscopic Surgery Unit, Hospital Vithas Vitoria, Vitoria-Gasteiz, Spain</footnote>

<footnote n="10">¹⁰Department of Orthopaedic and Trauma Surgery, Malteser Waldkrankenhaus, Erlangen, Germany</footnote>

<footnote n="11">¹¹Department of Orthopaedic Surgery, University of Rostock, Rostock, Germany</footnote>

<footnote n="12">¹²Department of Surgery, Service of Orthopaedics and Traumatology, EOC, Lugano, Switzerland</footnote>

<footnote n="13">¹³Faculty of Biomedical Sciences, Università Della Svizzera Italiana, Lugano, Switzerland</footnote>

<footnote n="14">¹⁴Arthrosport Clinic, Tel-Aviv, Israel</footnote>

<footnote n="15">¹⁵Rappaport Faculty of Medicine, Technion University Hospital (Israel)Institute of Technology), Haifa, Israel</footnote>

<footnote n="16">¹⁶Department of Orthopaedics, Hillel Yaffe Medical Center (HYMC), Hadera, Israel</footnote>
leading to the paper, and will take public responsibility for its content.

## ORCID

Yosef Sourugeon ID http://orcid.org/0000-0002-1994-3274

Carlotta Perucca Orfei ID http://orcid.org/0000-0001-6162-8668

## REFERENCES

1. Baksh, D., Yao, R. & Tuan, R.S. (2007) Comparison of proliferative and multilineage differentiation potential of human mesenchymal stem cells derived from umbilical cord and bone marrow. *Stem Cells*, 25(6), 1384-1392. Available from: https://doi.org/10.1634/stemcells.2006-0709

2. Benito, M.J. (2005) Synovial tissue inflammation in early and late osteoarthritis. *Annals of the Rheumatic Diseases*, 64(9), 1263-1267. Available from: https://doi.org/10.1136/ard.2004.025270

3. Berebichez-Fridman, R. & Montero-Olvera, P.R. (2018) Sources and clinical applications of mesenchymal stem cells. *Sultan Qaboos University Medical Journal* [SQUMJ], 18(3), 264. Available from: https://doi.org/10.18295/squmj.2018.18.03.002

4. Bertoni, L., Jacquet-Guibon, S., Branly, T., Desancé, M., Legendre, F., Melin, M. et al. (2021) Evaluation of allogeneic bone-marrow-derived and umbilical cord blood-derived mesenchymal stem cells to prevent the development of osteoarthritis in an equine model. *International Journal of Molecular Sciences*, 22(5), 2499. Available from: https://doi.org/10.3390/ijms22052499

5. Bhattacharjee, M., Escobar Ivirico, J.L., Kan, H.-M., Shah, S., Otsuka, T., Bordett, R. et al. (2022) Injectable amnion hydrogel-mediated delivery of adipose-derived stem cells for osteoarthritis treatment. *Proceedings of the National Academy of Sciences of the United States of America*, 119(4), e2120968119. Available from: https://doi.org/10.1073/pnas.2120968119

6. Bie, Y., Chen, Q., Xu, J., Ou, B., Chen, B., Guan, Y. et al. (2023) Human umbilical-cord-derived mesenchymal stem cells in combination with rapamycin reduce cartilage degradation via inhibition of the AKT/mTOR signaling pathway. *Immunopharmacology and Immunotoxicology*, 45(5), 549-557. Available from: https://doi.org/10.1080/08923973.2023.2189062

7. Boeuf, S. & Richter, W. (2010) Chondrogenesis of mesenchymal stem cells: role of tissue source and inducing factors. *Stem Cell Research & Therapy*, 1(4), 31. Available from: https://doi.org/10.1186/scrt31

8. Boffa, A., Perucca Orfei, C., Sourugeon, Y., Laver, L., Magalon, J., Sánchez, M. et al. (2023) Cell-based therapies have disease-modifying effects on osteoarthritis in animal models. A systematic review by the ESSKA Orthobiologic Initiative. Part 2: bone marrow-derived cell-based injectable therapies. *Knee Surgery, Sports Traumatology, Arthroscopy*, 31, 3230-3242. Available from: https://doi.org/10.1007/s00167-023-07320-3

9. Boffa, A., Salerno, M., Merli, G., De Girolamo, L., Laver, L., Magalon, J. et al. (2021) Platelet-rich plasma injections induce disease-modifying effects in the treatment of osteoarthritis in animal models. *Knee Surgery, Sports Traumatology, Arthroscopy*, 29(12), 4100-4121. Available from: https://doi.org/10.1007/s00167-021-06659-9

10. Bortoluzzi, A., Furini, F. & Scirè, C.A. (2018) Osteoarthritis and its management - epidemiology, nutritional aspects and environmental factors. *Autoimmunity Reviews*, 17(11), 1097-1104. Available from: https://doi.org/10.1016/j.autrev.2018.06.002

11. Broeckx, S.Y., Martens, A.M., Bertone, A.L., Van Brantegem, L., Duchateau, L., Van Hecke, L. et al. (2019) The use of equine chondrogenic-induced mesenchymal stem cells as a treatment for osteoarthritis: a randomised, double-blinded, placebo-controlled proof-of-concept study. *Equine Veterinary Journal*, 51(6), 787-794. Available from: https://doi.org/10.1111/evj.13089

12. Centeno, C.J. & Pastoriza, S.M. (2020) Past, current and future interventional orthobiologics techniques and how they relate to regenerative rehabilitation: a clinical commentary. *International Journal of Sports Physical Therapy*, 15(2), 301-325. Available from: https://doi.org/10.26603/ijspst202000301

13. Chan, D.-C., Chiu, C.-Y., Lan, K.-C., Weng, T.-I., Yang, R.-S. & Liu, S.-H. (2017) Transplantation of human skeletal muscle-derived progenitor cells ameliorates knee osteoarthritis in streptozotocin-induced diabetic mice. *Journal of Orthopaedic Research*, 35(9), 1886-1893. Available from: https://doi.org/10.1002/jor.23503

14. Chen, P., Tang, S., Gao, H., Zhang, H., Chen, C., Fang, Z. et al. (2022) Wharton's jelly mesenchymal stem cell-derived small extracellular vesicles as natural nanoparticles to attenuate cartilage injury via microRNA regulation. *International Journal of Pharmaceutics*, 623, 121952. Available from: https://doi.org/10.1016/j.ijpharm.2022.121952

15. Cheng, J.-H., Wang, C.-J., Chou, W.-Y., Hsu, S.-L., Chen, J.-H. & Hsu, T.-C. (2019) Comparison efficacy of ESWT and Wharton's jelly mesenchymal stem cell in early osteoarthritis of rat knee. *American Journal of Translational Research*, 11(2), 586-598. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6413288/

16. Chevalier, X., Ravaud, P., Maheu, E., Baron, G., Rialland, A., Vergnaud, P. et al. French Section of Osteoarthritis. (2015) Adalimumab in patients with hand osteoarthritis refractory to analgesics and NSAIDs: a randomised, multicentre, double-blind, placebo-controlled trial. *Annals of the Rheumatic Diseases*, 74(9), 1697-1705. Available from: https://doi.org/10.1136/annrheumdis-2014-205348

17. Daems, R., Van Hecke, L., Schwarzkopf, I., Depuydt, E., Broeckx, S.Y., David, M. et al. (2019) A feasibility study on the use of equine chondrogenic induced mesenchymal stem cells as a treatment for natural occurring osteoarthritis in dogs. *Stem Cells International*, 2019(1), 1-11. Available from: https://doi.org/10.1155/2019/4587594

18. Desai, S., Dooner, M., Newberry, J., Twomey-Kozak, J., Molino, J., Trivedi, J. et al. (2022) Stable human cartilage progenitor cell line stimulates healing of meniscal tears and attenuates post-traumatic osteoarthritis. *Frontiers in Bioengineering and Biotechnology*, 10, 970235. Available from: https://doi.org/10.3389/fbioe.2022.970235

19. Dhillon, J., Kraeutler, M.J., Belk, J.W. & Scillia, A.J. (2022) Umbilical cord-derived stem cells for the treatment of knee osteoarthritis: a systematic review. *Orthopaedic Journal of Sports Medicine*, 10(7), 232596712211044. Available from: https://doi.org/10.1177/23259671221104409

20. Di Matteo, B., Anzillotti, G., Gallese, A., Vitale, U., Gaggia, G.M.M.C., Ronzoni, F.L. et al. (2023) Placenta-derived products demonstrate good safety profile and overall satisfactory outcomes for treating knee osteoarthritis: a systematic review of clinical evidence. *Arthroscopy*, 39(8), 1892-1904. Available from: https://doi.org/10.1016/j.arthro.2023.03.033

21. Endrinaldi, E., Darwin, E., Zubir, N. & Revilla, G. (2019) The effect of mesenchymal stem cell Wharton's jelly on ADAMTS-4 and iNOS levels in osteoarthritis rat model. *Open Access Macedonian Journal of Medical Sciences*, 7(8), 1270-1275. Available from: https://doi.org/10.3889/oamjms.2019.155

22. Estakhri, F., Reza Panjehshahin, M., Tanideh, N., Gheisari, R., Azarpira, N. & Gholijani, N. (2021) Efficacy of combination therapy with apigenin and synovial membrane-derived mesenchymal
stem cells on knee joint osteoarthritis in a rat model. *Iranian Journal of Medical Sciences*, 46(5), 383-394. Available from: https://doi.org/10.30476/IJMS.2020.83686.1301

23. Fan, M., Zhang, J., Zhou, L., Chen, Z., Bao, R., Zheng, L. et al. (2022) Intra-articular injection of placental mesenchymal stromal cells ameliorates pain and cartilage anabolism/catabolism in knee osteoarthritis. *Frontiers in Pharmacology*, 13, 983850. Available from: https://doi.org/10.3389/fphar.2022.983850

24. Fan, M.-P., Si, M., Li, B.-J., Hu, G.-H., Hou, Y., Yang, W. et al. (2018) Cell therapy of a knee osteoarthritis rat model using precartilaginous stem cells. *European Review for Medical and Pharmacological Sciences*, 22(7), 2119-2125. Available from: https://doi.org/10.26355/eurrev_201804_14745

25. Ferracini, R., Alessio-Mazzola, M., Sonzogni, B., Stambazzi, C., Ursino, C., Roato, I. et al. (2023) Age and synovitis affect the results of the treatment of knee osteoarthritis with micro-fragmented autologous fat tissue. *Knee Surgery, Sports Traumatology, Arthroscopy*, 31(9), 3655-3664. Available from: https://doi.org/10.1007/s00167-022-07139-4

26. Flannery, C.R., Seaman, S.A., Buddin, K.E., Nasert, M.A., Semler, E.J., Kelley, K.L. et al. (2021) A novel placental tissue biologic, PTP-001, inhibits inflammatory and catabolic responses in vitro and prevents pain and cartilage degeneration in a rat model of osteoarthritis. *Osteoarthritis and Cartilage*, 29(8), 1203-1212. Available from: https://doi.org/10.1016/j.joca.2021.03.022

27. Geng, Y., Chen, J., Alahdal, M., Chang, C., Duan, L., Zhu, W. et al. (2020) Intra-articular injection of hUC-MSCs expressing miR-140-5p induces cartilage self-repairing in the rat osteoarthritis. *Journal of Bone and Mineral Metabolism*, 38(3), 277-288. Available from: https://doi.org/10.1007/s00774-019-01055-3

28. de Girolamo, L., Filardo, G. & Laver, L. (2023) Disease-modifying effects of orthobiologics in the treatment of knee osteoarthritis: the lesson learned from preclinical research models. *Knee Surgery, Sports Traumatology, Arthroscopy*, 31(12), 5286-5290. Available from: https://doi.org/10.1007/s00167-023-07423-x

29. Guerrero, E.N., Vega, S., Fu, C., De León, R., Beltran, D. & Solis, M.A. (2021) Increased proliferation and differentiation capacity of placenta-derived mesenchymal stem cells from women of median maternal age correlates with telomere shortening. *Aging*, 13(22), 24542-24559. Available from: https://doi.org/10.18632/aging.203724

30. Harrell, C.R., Gazdic, M., Fellabaum, C., Jovicic, N., Djonov, V., Arsenijevic, N. et al. (2019) Therapeutic potential of amniotic fluid derived mesenchymal stem cells based on their differentiation capacity and immunomodulatory properties. *Current Stem Cell Research & Therapy*, 14(4), 327-336. Available from: https://doi.org/10.2174/1574888X14666190222201749

31. Hatsushika, D., Muneta, T., Nakamura, T., Horie, M., Koga, H., Nakagawa, Y. et al. (2014) Repetitive allogeneic intraarticular injections of synovial mesenchymal stem cells promote meniscus regeneration in a porcine massive meniscus defect model. *Osteoarthritis and Cartilage*, 22(7), 941-950. Available from: https://doi.org/10.1016/j.joca.2014.04.028

32. Hawker, G.A. (2019) Osteoarthritis is a serious disease. *Clinical and Experimental Rheumatology*, 37 Suppl 120(5), 3-6. Available from: https://pubmed.ncbi.nlm.nih.gov/31621562/

33. Hooijmans, C.R., Rovers, M.M., de Vries, R.B., Leenaars, M., Ritskes-Hoitinga, M. & Langendam, M.W. (2014) SYRCLE's risk of bias tool for animal studies. *BMC Medical Research Methodology*, 14, 43. Available from: https://doi.org/10.1186/1471-2288-14-43

34. Hsu, C.-C., Cheng, J.-H., Wang, C.-J., Ko, J.-Y., Hsu, S.-L. & Hsu, T.-C. (2020) Shockwave therapy combined with autologous adipose-derived mesenchymal stem cells is better than with human umbilical cord Wharton's jelly-derived mesenchymal stem cells on knee osteoarthritis. *International Journal of Molecular Sciences*, 21(4), 1217. Available from: https://doi.org/10.3390/ijms21041217

35. Jin, H., Bae, Y., Kim, M., Kwon, S.-J., Jeon, H., Choi, S. et al. (2013) Comparative analysis of human mesenchymal stem cells from bone marrow, adipose tissue, and umbilical cord blood as sources of cell therapy. *International Journal of Molecular Sciences*, 14(9), 17986-18001. Available from: https://doi.org/10.3390/ijms140917986

36. Kern, S., Eichler, H., Stoeve, J., Klüter, H. & Bieback, K. (2006) Comparative analysis of mesenchymal stem cells from bone marrow, umbilical cord blood, or adipose tissue. *Stem Cells*, 24(5), 1294-1301. Available from: https://doi.org/10.1634/stemcells.2005-0342

37. Kim, H., Yang, G., Park, J., Choi, J., Kang, E. & Lee, B.-K. (2019) Therapeutic effect of mesenchymal stem cells derived from human umbilical cord in rabbit temporomandibular joint model of osteoarthritis. *Scientific Reports*, 9(1), 13854. Available from: https://doi.org/10.1038/s41598-019-50435-2

38. Kim, M., Ahn, J., Lee, J., Song, S., Lee, S., Lee, S. et al. (2022) Combined mesenchymal stem cells and cartilage acellular matrix injection therapy for osteoarthritis in goats. *Tissue Engineering and Regenerative Medicine*, 19(1), 177-187. Available from: https://doi.org/10.1007/s13770-021-00407-3

39. Kim, S.E., Pozzi, A., Yeh, J., Lopez-Velazquez, M., Au Yong, J.A., Townsend, S. et al. (2019) Intra-articular umbilical cord derived mesenchymal stem cell therapy for chronic elbow osteoarthritis in dogs: a double-blinded, placebo-controlled clinical trial. *Frontiers in Veterinary Science*, 6, 474. Available from: https://doi.org/10.3389/fvets.2019.00474

40. Kim, Y.S., Kim, Y.I. & Koh, Y.G. (2021) Intra-articular injection of human synovium-derived mesenchymal stem cells in beagles with surgery-induced osteoarthritis. *The Knee*, 28, 159-168. Available from: https://doi.org/10.1016/j.knee.2020.11.021

41. Kimmerling, K.A., Gomoll, A.H., Farr, J. & Mowry, K.C. (2022) Amniotic suspension allograft improves pain and function in a rat meniscal tear-induced osteoarthritis model. *Arthritis Research & Therapy*, 24(1), 63. Available from: https://doi.org/10.1186/s13075-022-02750-9

42. Kimmerling, K.A., Gomoll, A.H., Farr, J. & Mowry, K.C. (2020) Amniotic suspension allograft modulates inflammation in a rat pain model of osteoarthritis. *Journal of Orthopaedic Research*, 38(5), 1141-1149. Available from: https://doi.org/10.1002/jor.24559

43. Ledesma-Martínez, E., Mendoza-Núñez, V.M. & Santiago-Osorio, E. (2016) Mesenchymal stem cells derived from dental pulp: a review. *Stem Cells International*, 2016, 4709572. Available from: https://doi.org/10.1155/2016/4709572

44. Lin, W., Yang, Z., Shi, L., Wang, H., Pan, Q., Zhang, X. et al. (2022) Alleviation of osteoarthritis by intra-articular transplantation of circulating mesenchymal stem cells. *Biochemical and Biophysical Research Communications*, 636(Pt 1), 25-32. Available from: https://doi.org/10.1016/j.bbrc.2022.10.064

45. Liu, A., Chen, J., Zhang, J., Zhang, C., Zhou, Q., Niu, P. et al. (2021) Intra-articular injection of umbilical cord mesenchymal stem cells loaded with graphene oxide granular lubrication ameliorates inflammatory responses and osteoporosis of the subchondral bone in rabbits of modified papain-induced osteoarthritis. *Frontier Endocrinology*, 12, 822294. Available from: https://doi.org/10.3389/fendo.2021.822294

46. Liu, P., Gurung, B., Afzal, I., Santin, M., Sochart, D.H., Field, R.E. et al. (2022) The composition of cell-based therapies obtained from point-of-care devices/systems which mechanically dissociate lipoaspirate: a scoping review of the literature. *Journal of Experimental Orthopaedics*, 9(1), 103. Available from: https://doi.org/10.1186/s40634-022-00537-0

47. Maraldi, T. & Russo, V. (2022) Amniotic fluid and placental membranes as sources of stem cells: progress and challenges. *International Journal of Molecular Sciences*, 23(10), 5362. Available from: https://doi.org/10.3390/ijms23105362
48. Marino-Martínez, I.A., Martínez-Castro, A.G., Peña-Martínez, V.M., Acosta-Olivo, C.A., Vilchez-Cavazos, F., Guzmán-López, A. et al. (2019) Human amniotic membrane intra-articular injection prevents cartilage damage in an osteoarthritis model. *Experimental and Therapeutic Medicine*, 17(1), 11–16. Available from: https://doi.org/10.3892/etm.2018.6924

49. Matsumoto, T., Cooper, G.M., Gharaibeh, B., Meszaros, L.B., Li, G., Usas, A. et al. (2009) Cartilage repair in a rat model of osteoarthritis through intraarticular transplantation of muscle-derived stem cells expressing bone morphogenetic protein 4 and soluble Flt-1. *Arthritis & Rheumatology*, 60(5), 1390–1405. Available from: https://doi.org/10.1002/art.24443

50. Mifune, Y., Matsumoto, T., Takayama, K., Ota, S., Li, H., Meszaros, L.B. et al. (2013) The effect of platelet-rich plasma on the regenerative therapy of muscle derived stem cells for articular cartilage repair. *Osteoarthritis and Cartilage*, 21(1), 175–185. Available from: https://doi.org/10.1016/j.joca.2012.09.018

51. Mostafa, A., Korayem, H.E., Fekry, E. & Hosny, S. (2021) The effect of intra-articular versus intravenous injection of mesenchymal stem cells on experimentally-induced knee joint osteoarthritis. *Journal of Microscopy and Ultrastructure*, 9(1), 31–38. Available from: https://doi.org/10.4103/JMAU.JMAU_2_20

52. Nagamura-Inoue, T. (2014) Umbilical cord-derived mesenchymal stem cells: their advantages and potential clinical utility. *World Journal of Stem Cells*, 6(2), 195–202. Available from: https://doi.org/10.4252/wjsc.v6.i2.195

53. Perry, J., McCarthy, H.S., Bou-Gharios, G., van 't Hof, R., Milner, P.I., Mennan, C. et al. (2020) Injected human umbilical cord-derived mesenchymal stromal cells do not appear to elicit an inflammatory response in a murine model of osteoarthritis. *Osteoarthritis and Cartilage Open*, 2(2), 100044. Available from: https://doi.org/10.1016/j.ocarto.2020.100044

54. Perry, T.A., Parkes, M.J., Hodgson, R.J., Felson, D.T., Arden, N.K. & O'Neill, T.W. (2020) Association between bone marrow lesions & synovitis and symptoms in symptomatic knee osteoarthritis. *Osteoarthritis and Cartilage*, 28(3), 316–323. Available from: https://doi.org/10.1016/j.joca.2019.12.002

55. Pers, Y.-M., Ruiz, M., Noël, D. & Jorgensen, C. (2015) Mesenchymal stem cells for the management of inflammation in osteoarthritis: state of the art and perspectives. *Osteoarthritis and Cartilage*, 23(11), 2027–2035. Available from: https://doi.org/10.1016/j.joca.2015.07.004

56. Perucca Orfei, C., Boffa, A., Sourugeon, Y., Laver, L., Magalon, J., Sánchez, M. et al. (2023) Cell-based therapies have disease-modifying effects on osteoarthritis in animal models. A systematic review by the ESSKA Orthobiologic Initiative. Part 1: adipose tissue-derived cell-based injectable therapies. *Knee Surgery, Sports Traumatology, Arthroscopy*, 31(2), 641–655. Available from: https://doi.org/10.1007/s00167-022-07063-7

57. Pisciotta, A., Bertoni, L., Vallarola, A., Bertani, G., Mecugni, D. & Carnevale, G. (2020) Neural crest derived stem cells from dental pulp and tooth-associated stem cells for peripheral nerve regeneration. *Neural Regeneration Research*, 15(3), 373–381. Available from: https://doi.org/10.4103/1673-5374.266043

58. Qiong, J., Xia, Z., Jing, L. & Haibin, W. (2020) Synovial mesenchymal stem cells effectively alleviate osteoarthritis through promoting the proliferation and differentiation of meniscus chondrocytes. *European Review for Medical and Pharmacological Sciences*, 24(4), 1645–1655. Available from: https://doi.org/10.26355/eurrev_202002_20338

59. Raines, A.L., Shih, M.-S., Chua, L., Su, C.-W., Tseng, S.C.G. & O'Connell, J. (2017) Efficacy of particulate amniotic membrane and umbilical cord tissues in attenuating cartilage destruction in an osteoarthritis model. *Tissue Engineering. Part A*, 23(1–2), 12–19. Available from: https://doi.org/10.1089/ten.tea.2016.0088

60. Razak, H.R.B.A., Corona, K., Totlis, T., Chan, L.Y.T., Salreta, J.F., Sleiman, O. et al. (2023) Mesenchymal stem cell implantation provides short-term clinical improvement and satisfactory cartilage restoration in patients with knee osteoarthritis but the evidence is limited: a systematic review performed by the early-osteoarthritis group of ESSKA-European knee associates section. *Knee Surgery, Sports Traumatology, Arthroscopy*, 31(12), 5306–5318. Available from: https://doi.org/10.1007/s00167-023-07575-w

61. Reale, D., Feltri, P., Franceschini, M., de Girolamo, L., Laver, L., Magalon, J. et al. (2023) Biological intra-articular augmentation for osteotomy in knee osteoarthritis: strategies and results. *Knee Surgery, Sports Traumatology, Arthroscopy*, 31(10), 4327–4346. Available from: https://doi.org/10.1007/s00167-023-07469-x

62. Rebelatto, C.K., Aguiar, A.M., Moretão, M.P., Senegaglia, A.C., Hansen, P., Barchiki, F. et al. (2008) Dissimilar differentiation of mesenchymal stem cells from bone marrow, umbilical cord blood, and adipose tissue. *Experimental Biology and Medicine*, 233(7), 901–913. Available from: https://doi.org/10.3181/0712-RM-356

63. Reece, D.S., Burnsed, O.A., Parchinski, K., Marr, E.E., White, R.M., Salazar-Noratto, G.E. et al. (2020) Reduced size profile of amniotic membrane particles decreases osteoarthritis therapeutic efficacy. *Tissue Engineering. Part A*, 26(1–2), 28–37. Available from: https://doi.org/10.1089/ten.tea.2019.0074

64. Roemer, F.W., Guermazi, A., Felson, D.T., Niu, J., Nevitt, M.C., Crema, M.D. et al. (2011) Presence of MRI-detected joint effusion and synovitis increases the risk of cartilage loss in knees without osteoarthritis at 30-month follow-up: the MOST study. *Annals of the Rheumatic Diseases*, 70(10), 1804–1809. Available from: https://doi.org/10.1136/ard.2011.150243

65. Sakaguchi, Y., Sekiya, I., Yagishita, K. & Muneta, T. (2005) Comparison of human stem cells derived from various mesenchymal tissues: superiority of synovium as a cell source. *Arthritis & Rheumatism*, 52(8), 2521–2529. Available from: https://doi.org/10.1002/art.21212

66. Sampath, S.J.P., Kotikalapudi, N. & Venkatesan, V. (2021) A novel therapeutic combination of mesenchymal stem cells and stigmasterol to attenuate osteoarthritis in rodent model system-a proof of concept study. *Stem Cell Investigation*, 8, 5. Available from: https://doi.org/10.21037/sci-2020-048

67. Sanchez-Lopez, E., Coras, R., Torres, A., Lane, N.E. & Guma, M. (2022) Synovial inflammation in osteoarthritis progression. *Nature Reviews Rheumatology*, 18(5), 258–275. Available from: https://doi.org/10.1038/s41584-022-00749-9

68. Saulnier, N., Viguier, E., Perrier-Groult, E., Chenu, C., Pillet, E., Roger, T. et al. (2015) Intra-articular administration of xenogeneic neonatal mesenchymal stromal cells early after meniscal injury down-regulates metalloproteinase gene expression in synovium and prevents cartilage degradation in a rabbit model of osteoarthritis. *Osteoarthritis and Cartilage*, 23(1), 122–133. Available from: https://doi.org/10.1016/j.joca.2014.09.007

69. Sellam, J. & Berenbaum, F. (2010) The role of synovitis in pathophysiology and clinical symptoms of osteoarthritis. *Nature Reviews Rheumatology*, 6(11), 625–635. Available from: https://doi.org/10.1038/nrrheum.2010.159

70. Seol, D., McCabe, D.J., Choe, H., Zheng, H., Yu, Y., Jang, K. et al. (2012) Chondrogenic progenitor cells respond to cartilage injury. *Arthritis and Rheumatism*, 64(11), 3626–3637. Available from: https://doi.org/10.1002/art.34613

71. Tong, W., Zhang, X., Zhang, Q., Fang, J., Liu, Y., Shao, Z. et al. (2020) Multiple umbilical cord-derived MSCs administrations attenuate rat osteoarthritis progression via preserving articular cartilage superficial layer cells and inhibiting synovitis. *Journal of Orthopaedic Translation*, 23, 21–28. Available from: https://doi.org/10.1016/j.jot.2020.03.007
72. Vangsness CT, J.r, Sternberg, H. & Harris, L. (2015) Umbilical cord tissue offers the greatest number of harvestable mesenchymal stem cells for research and clinical application: a literature review of different harvest sites. *Arthroscopy*, 31(9), 1836–1843.
Available from: https://doi.org/10.1016/j.arthro.2015.03.014

73. Veronesi, F., Fini, M., Martini, L., Berardinelli, P., Russo, V., Filardo, G. et al. (2022) In vivo model of osteoarthritis to compare allogenic amniotic epithelial stem cells and autologous adipose derived cells. *Biology*, 11(5), 681. Available from: https://doi.org/10.3390/biology11050681

74. Vidal, M.A., Walker, N.J., Napoli, E. & Borjesson, D.L. (2012) Evaluation of senescence in mesenchymal stem cells isolated from equine bone marrow, adipose tissue, and umbilical cord tissue. *Stem Cells and Development*, 21(2), 273–283. Available from: https://doi.org/10.1089/scd.2010.0589

75. Walczak, B.E., Jiao, H., Lee, M.-S. & Li, W.-J. (2021) Repro-grammed synovial fluid-derived mesenchymal stem/stromal cells acquire enhanced therapeutic potential for articular carti-lage repair. *Cartilage*, 13(2_suppl), 530S–543S. Available from: https://doi.org/10.1177/19476035211040858

76. Wang, A.-T., Zhang, Q.-F., Wang, N.-X., Yu, C.-Y., Liu, R.-M., Luo, Y. et al. (2020) Cocktail of hyaluronic acid and human amniotic mesenchymal cells effectively repairs cartilage injuries in sodium iodoacetate-induced osteoarthritis rats. *Frontiers in Bioengineering and Biotechnology*, 8, 87. Available from: https://doi.org/10.3389/fbioe.2020.00087

77. Wang, B., Liu, W., Li, J.J., Chai, S., Xing, D., Yu, H. et al. (2022) A low dose cell therapy system for treating osteoarthritis: In vivo study and in vitro mechanistic investigations. *Bioactive Materials*, 7, 478–490. Available from: https://doi.org/10.1016/j.bioactmat.2021.05.029

78. Willett, N.J., Thote, T., Lin, A.S., Moran, S., Raji, Y., Sridaran, S. et al. (2014) Intra-articular injection of micronized dehydrated human amnion/chorion membrane attenuates osteoarthritis development. *Arthritis Research & Therapy*, 16(1), R47. Available from: https://doi.org/10.1186/ar4476

79. Xia, Q., Zhu, S., Wu, Y., Wang, J., Cai, Y., Chen, P. et al. (2015) Intra-articular transplantation of atsstrin-transduced mesenchymal stem cells ameliorate osteoarthritis development. *Stem Cells Translational Medicine*, 4(5), 523–531. Available from: https://doi.org/10.5966/sctm.2014-0200

80. Yan, L., Zhou, L., Yan, B., Zhang, L., Du, W., Liu, F. et al. (2020) Growth factors-based beneficial effects of platelet lysate on umbilical cord-derived stem cells and their synergistic use in osteoarthritis treatment. *Cell Death & Disease*, 11(10), 857. Available from: https://doi.org/10.1038/s41419-020-03045-0

81. Zare, R., Tanideh, N., Nikahval, B., Mirtalebi, M.S., Ahmadi, N., Zarea, S. et al. (2020) Are stem cells derived from synovium and fat pad able to treat induced knee osteoarthritis in rats?

*International Journal of Rheumatology*, 2020, 1–8. Available from: https://doi.org/10.1155/2020/9610261

82. Zeng, J., Wang, F. & Mao, M. (2016) Co-culture of fibroblast-like synoviocytes with umbilical cord-mesenchymal stem cells inhibits expression of pro-inflammatory proteins, induces apoptosis and promotes chondrogenesis. *Molecular Medicine Reports*, 14(4), 3887–3893. Available from: https://doi.org/10.3892/mmr.2016.5721

83. Zhang, B., Wang, B., Li, S., Luo, D., Zhan, X., Chen, S. et al. (2018) Evaluation of the curative effect of umbilical cord mesenchymal stem cell therapy for knee arthritis in dogs using imaging technology. *Stem Cells International*, 2018, 1–12. Available from: https://doi.org/10.1155/2018/1983025

84. Zhang, Q., Xiang, E., Rao, W., Zhang, Y.Q., Xiao, C.H., Li, C.Y. et al. (2021) Intra-articular injection of human umbilical cord mesenchymal stem cells ameliorates monosodium iodoacetate-induced osteoarthritis in rats by inhibiting cartilage degradation and inflammation. *Bone & Joint Research*, 10(3), 226–236. Available from: https://doi.org/10.1302/2046-3758.103.BJR-2020-0206.R2

85. Zhang, X., Liu, S., Wang, Z., Luo, C., Dai, Z., Sun, J. et al. (2021) Implanted 3D gelatin microcryogel enables low-dose cell therapy for osteoarthritis by preserving the viability and function of umbilical cord MSCs. *Chemical Engineering Journal*, 416, 129140. Available from: https://doi.org/10.1016/j.cej.2021.129140

## SUPPORTING INFORMATION

Additional supporting information can be found online in the Supporting Information section at the end of this article.

**How to cite this article:** Sourugeon, Y., Boffa, A., Perucca Orfei, C., de Girolamo, L., Magalon, J., Sánchez, M. et al. (2024) Cell-based therapies have disease-modifying effects on osteoarthritis in animal models: A systematic review by the ESSKA Orthobiologic Initiative. Part 3: Umbilical cord, placenta, and other sources for cell-based injectable therapies. *Knee Surgery, Sports Traumatology, Arthroscopy*, 1–14. https://doi.org/10.1002/ksa.12472