THU0061 EVALUATION OF SAFETY AND EVOLUTION OF OSTEOARTHRITIC JOINTS AFTER THE ADMINISTRATION OF HETEROLOGOUS MESENCHYMAL STROMAL CELLS IN AN ANIMAL MODEL

Background:

One of the main osteoarthritis (OA) consequences is the cartilage loss. Nowadays there is not cure for the OA, so there is an intense research focused on finding a therapy to solve this problem. In this paradigm heterologous mesenchymal stromal cells (MSCH) rise as a solution. Different studies used them as a cellular therapy in order to regenerate damaged cartilage. Furthermore, MSCH have shown anti-inflammatory effects.

Objectives:

1) Study the safety of a single intraarticular injection of MSCH derived from healthy canine fat tissue (adMSCH) in OA joints of dogs

2) Observe the evolution of functionality and range of articular mobility of these treated joints 6 months after the injection.

Methods:

adMSCH obtained (n=10) were phenotypically characterized by flow cytometry, including the Major Histocompatibility Complex type II (MHC-II). Those with the best morphology and growth (n=5) were used for the injection.

The infiltrated dogs (n=7) met our inclusion/exclusion criteria. The adMSCH were injected in 11 joints by 1 million of cells/kilogram of weight.

Before the infiltration we evaluated the joints (basal visit, BV), the vital signs and the animal pain by the owner (Visual Analogical Scale, VAS). The same data were collected one week after the infiltration (V1) and also studied the injected zone. Six months after treatment (V2), joint functionality and range of articular mobility were evaluated, also data of behavioural changes and pain observed by the owners.

Results:

All cells obtained were negative for the MHC-II (0.45 ± 0.32).

Vital signs did not change between BV and V1. No dog suffered by severe inflammation of the injected joint. One of them during two days had difficulty to support the load in the posterior limbs, but at the third day it performed that without difficulty. Other dog suffered mild inflammation which was solved in two days. The other animals did not show any adverse effect after the infiltration. In the V1 none of them showed any inflammation in the joint. The pain evaluation by the owners showed that all dogs have less pain or it did not increase since BV. This indicate that after the infiltration the animals did not suffer a pain increase.

Data collected in V2 showed that the joint functionality tend to improve, one of the items showing significant differences between BV and V2. The range of articular mobility did not have neither differences nor tendencies to the improvement (Table 1).

Table 1.

Functionality and range of articular mobility comparison between BV and V2. Visits column show the number of joints in that state

VariableAnswersVisitst-student (p-value)nBVV2FUNCTIONALITYLoad changesNormal370.09511Change load84Support fingers00No support00Load changes when getting upCorrectly160.024*11Position modification105Difficulty to get up00No get up00Lameness in coldNo lameness120.06211Mild lameness69Intense lameness40No support00Lameness when warmedNo lameness130.10611Mild lameness88Intense lameness20No support00RANGE OF ARTICULAR MOBILITYArticular passive manual mobilityWithout pain000.40011Mild pain35Raised pain86Disabling pain00Flexion limitationTotal flexion980.75011Mild limitation12Severe limitation11Extension limitationTotal extension030.74911Mild limitation94Severe limitation24

*. Statistical significance stablished at P ≤ 0.05

Conclusion:

The administration of adMSCH did not show adverse effects, rejection, infection or complications, only a probably of a mild inflammation in the treated zone. Also, joint functionality tends to improve, so these cells seem to have, at least, an anti-inflammatory effect into the OA joint.

Acknowledgments:

Special thanks to the owners of the dogs who participated in this study.

Disclosure of Interests:

Paula-Catarina Sánchez-Pedreira: None declared, Ángela Vela-Anero: None declared, Nuria Otero Queijas: None declared, María Lorenzo Toja: None declared, Andrés Somaza Serantes: None declared, Tamara Hermida Gómez: None declared, Francisco J. Blanco Grant/research support from: Sanofi-Aventis, Lilly, Bristol MS, Amgen, Pfizer, Abbvie, TRB Chemedica International, Glaxo SmithKline, Archigen Biotech Limited, Novartis, Nichi-iko pharmaceutical Co, Genentech, Jannsen Research & Development, UCB Biopharma, Centrexion Theurapeutics, Celgene, Roche, Regeneron Pharmaceuticals Inc, Biohope, Corbus Pharmaceutical, Tedec Meiji Pharma, Kiniksa Pharmaceuticals, Ltd, Gilead Sciences Inc, Consultant of: Lilly, Bristol MS, Pfizer

Long-term effects of hydrogen sulfide on the anabolic-catabolic balance of articular cartilage in vitro

Healthy cartilage maintenance relies on an equilibrium among the anabolic and catabolic processes in chondrocytes. With the onset of osteoarthritis (OA), increased interleukin (IL)-1β levels induce an inhibition of the synthesis of extracellular matrix (ECM) proteins, as well as an increase in proteases. This eventually leads to a predominance of the catabolic phenotype and the progressive loss of articular cartilage. Hydrogen sulfide (H₂S) is a small gaseous molecule recognized as the third endogenous gasotransmitter. When administered exogenously, it has shown anti-inflammatory and anti-catabolic properties in several in vitro and in vivo models. Here, OA cartilage disks were co-cultured in vitro with IL-1β (5 ng/ml) and NaSH or GYY4137 (200 or 1000 μM) for 21 days. The ability of these two H₂S-producing compounds to avoid long term extracellular matrix (ECM) destruction was evaluated. We used a glycosaminoglycan (GAG) quantification kit histology and immunohistochemistry (IHC) to evaluate matrix proteins degradation and matrix metalloproteinases (MMP) abundance. Through the GAGs quantification assay, safranin O (S-O) and toluidine blue (TB) stains, and keratan/chondroitin sulfate (KS/ChS) IHCs it was shown that co-stimulation with H₂S-forming reagents effectively avoided GAGs destruction. Both Masson's trichrome (MT) stain and collagen (col) type II IHC, as well as aggrecan (agg) IHC demonstrated that not only were these proteins protected but even promoted, their abundance being higher than in the basal condition. Further, stains also demonstrated that positivity in the inter-territorial and intra-cellular for the different matrix components were rescued, suggesting that NaSH and GYY4137 might also have pro-anabolic effects. In addition, a clear protective effect against the increased MMPs levels was seen, since increased MMP3 and 13 levels were subsequently reduced with the co-stimulation with sulfide compounds. In general, GYY4137 was more effective than NaSH, and increasing the dose improved the results. This study demonstrates that H₂S anti-catabolic effects, which had been previously proven in short-term (24-48 h) in vitro cellular models, are maintained over time directly in OA cartilage tissue.