The Chondrogenic Potential of Progenitor Cells Derived from Peripheral Blood: A Systematic Review

Adjunct treatment with ozone to enhance therapy of knee osteoarthritis: preliminary results

Knee osteoarthritis (knee OA), commonly known as gonarthrosis, is a chronic pathology involving knee at the joint level causing progressive pain, stiffness and difficulty in ambulation and leg movements. So far in situ infiltration therapies such as platelet rich plasma, conditioned autologous serum or hyaluronic acid, provided some encouraging though limited hopes for a routinely recommended therapy for knee OA. Recent clinical successful observations about the use of whole autologous blood ozonated with a calibrated mixture of oxygen and ozone, has promoted the present research study, in order to treat knee OA. A number of 250 patients suffering with knee OA of different Ahlback scores, were treated with infiltration of ozonated blood and evaluated for their WOMAC and Lequesne indexes, pre- and post-treatment, to evaluate pain, disability and stiffness. Patients recovered about 50% of their health status, reducing pain, stiffness and disability by only 5 sessions, one/week, with 20 μg/ml O3 ozonated autologous blood knee infiltrations. The evidence asks for further supporting results yet encourages our efforts to go ahead in this research issue. Key Points •The oxygen-ozone therapy via ozonated blood infiltration was used in this study. •Ozone reduced pain, disability, and stiffness in both female and male patients. •The treatment with ozone improved WOMAC both in type I and type II Ahlback knee OA. •The oxygen-ozone therapy via ozonated blood ameliorated Lequesne functional index.

The Oxygen-Ozone Adjunct Medical Treatment According to the Protocols from the Italian Scientific Society of Oxygen-Ozone Therapy: How Ozone Applications in the Blood Can Influence Clinical Therapy Success via the Modulation of Cell Biology and Immunity

BACKGROUND

Ozone is an allotrope of oxygen whose use in medicine has rapidly grown in recent years. Ozonated blood allows for the use of ozone in a safe modality, as plasma and blood cells are endowed with an antioxidant system able to quench ozone's pro-oxidant property and to elicit the Nrf2/Kwap1/ARE pathway.

METHODS

We present two clinical studies, a case-series (six patients) observational study adopting ozone as a major autohemotherapy and topical ozone to address infected post-surgical wounds with multi-drug resistant bacteria and an observational study (250 patients) using ozonated blood for treating knee osteoarthritis.

RESULTS

Ozonated blood via major autohemotherapy reduced the extent of infections in wounds, reduced the inflammatory biomarkers by more than 75% and improved patients' QoL, whereas ozonated blood via minor autohemotherapy improved significantly (p < 0.001) WOMAC and Lequesne's parameters in knee osteoarthritis.

CONCLUSIONS

The models described, i.e., ozone autohemotherapy in wound antimicrobial treatment and ozonated blood in knee osteoarthrosis, following our protocols, share the outstanding ability of ozone to modulate the innate immune response and address bacterial clearance as well as inflammation and pain.

[Biological characteristics of sheep peripheral blood mesenchymal stem cell]

OBJECTIVE

To obtain eripheral blood mesenchymal stem cells (PBMSCs) from sheep and rabbits by continuous mobilization of granulocyte colony-stimulating factor (G-CSF), and by comparing the success rates, cell yields and biological characteristics of the two sources of PBMSCs, and to provide the experimental basis for the preclinical study of PBMSCs transplantation to repair articular cartilage injury and cartilage tissue engineering.

METHODS

Through morphological characteristics, flow cytometry analysis of its surface markers, and induction of trilineage differentiation of the two cells in vitro (ie: adipogenic differentiation, osteogenic differentiation, chondrogenic differentiation), the obtained cells were finally confirmed to be PBMSCs. The colony-forming units (CFUs) and the acquisition success rates of the two PBMSCs were counted and compared, and the production of the second generation of the two PBMSCs was counted and compared by hemocytometer, and the cell counting kit-8 was used to detect the doubling time of the two PBMSCs, and the results of trilineage differentiation were quantitatively analyzed by image processing.

RESULTS

Microscopically, the PBMSCs of fusiform sheep and rabbits were arranged in fish group, and the second generation of sheep and rabbit PBMSCs expressed CD44 and CD90, but not CD34 and CD45. The induction of trilineage differentiation of the two cells in vitro were successful. The CFUs of primary sheep and rabbits PBMSCs were: 7.27±1.56, 5.73±1.62, and the success rate of acquisition of sheep and rabbits PBMSCs were 78.57% and 36.67%. The number of the second-generation sheep and rabbits PBMSCs that obtained per milliliter of peripheral blood were: 29 582±2 138, 26 732±2 286, and the cell doubling times (h) of the third-generation sheep and rabbits PBMSCs were: 22.32±0.28, 33.21±0.64, the cell doubling time (h) of the fourth generation sheep and rabbits PBMSCs were: 23.62±0.56, 35.30±0.38, and the quantitative lipid ratio of sheep and rabbit PBMSCs were: 7.77%±3.81%, 17.05%±1.52%, sheep and rabbit PBMSCs chondroglobus acid mucopolysaccharide positive ratios were: 11.67%±0.53%, 8.14%±0.57%. There were statistical differences among the above groups (P < 0.05).

CONCLUSION

The continuous mobilization of G-CSF to obtain sheep PBMSCs is more efficient. Sheep PBMSCs have more abundant yield and stronger proliferation ability.Sheep PBMSCs can produce more acidic mucopolysaccharides and have lower adipogenic abi-lity under appropriate conditions. Sheep PBMSCs have good research prospects in repair of articular cartilage injury with autologous stem cell transplantation and preclinical animal in vivo experiment of cartilage tissue engineering.This experiment provides further experimental basis for this kind of research.

Editorial Commentary: Peripheral Blood Stem Cells Mobilization Using Granulocyte Colony-Stimulating Factor for Articular Cartilage Injuries: Wake Them Up and Make Them Come to You!

Articular cartilage injuries constitute a prevalent musculoskeletal problem in the general population. Restorative cartilage procedures are specifically challenging, as recapitulating hyaline cartilage can be difficult, thus compromising clinical outcomes. Progenitor cells for the treatment of articular cartilage injuries constitute a promising therapeutic method that has been increasing exponentially. Progenitor cells can be obtained from many different human tissues, such as bone marrow, adipose tissue, and muscle, as well as from peripheral blood after mobilizing stem cells from bone marrow with granulocyte colony-stimulating factor simulation. The minimally invasiveness, low complication rate, and efficacy of peripheral blood stem cells has gained significant attention and rapidly has become a promising source of progenitor cell delivery in the past decade.

Concentration Changes of Peripheral Blood Mesenchymal Stem Cells of Sprague Dawley Rats during Distraction Osteogenesis

Objectives

To observe the changes in the concentrations of circulating peripheral blood mesenchymal stem cells (PBMSCs) in Sprague Dawley (SD) rats and explore the pattern of changes in PBMSCs during the process of distraction osteogenesis.

Methods

SD rats were randomly divided into the osteotomy with lengthening group (lengthening group), the osteotomy without lengthening group (osteotomy group), and the blank control group (control group). Each group included 24 rats. Percutaneous pinning with external fixation of the left femur was carried out in lengthening group and osteotomy group, but control group received no surgical treatment. On day 5 after operation, continuous traction was carried out at a rate of 0.25 mm/d in lengthening group, while no traction was carried out in osteotomy group. Peripheral blood was collected from all rats on days 1, 3, 7, and 16 after the start of traction. PBMSCs were isolated by density gradient centrifugation. CD105, CD34, and CD45 were selected as cell surface markers. The concentration of PBMSCs was detected by flow cytometry and compared between groups at different time points. X‐ray films were taken during and after the operation to observe whether the osteotomy end was pulled and the growth and mineralization of the new bone in the osteogenic area of the femur. Color ultrasound was used to monitor the width of the distraction space, the formation of new bone, and the blood supply of soft tissue around the distraction.

Results

All rats were able to tolerate the operation well, and the external fixation was firm and reliable. X‐ray showed that, in lengthening group, the distraction space of femur gradually widened and new bone gradually formed in the distraction space; after 8 weeks, the samples were taken out, which showed that the new bone tissue in the lengthened area healed well. In osteotomy group, the average healing time of osteotomy was (7.12 ± 0.78) weeks. Ultrasonic examination showed that after the end of traction, the high echo callus shadow was seen in the traction space, and the blood flow signal was obviously rich at an earlier stage. In lengthening group and osteotomy group, the average concentrations of PBMSCs (3.02% ± 0.87% vs 2.95% ± 0.74%, respectively) were significantly increased in the early stage after osteotomy, and the average concentrations of PBMSCs on days 3, 7, and 16 after the start of traction were 5.34% ± 1.13% vs 3.28% ± 1.22%; 6.41% ± 1.05% vs 3.16% ± 0.92%; and 5.94% ± 1.23% vs 1.48% ± 0.52%, respectively. The concentration of PBMSCs in peripheral blood of lengthening group and osteotomy group was the same at osteotomy stage, and the difference between the two groups was not statistically significant (P > 0.05). After that, compared with lengthening group, the concentration of PBMSCs in osteotomy group gradually decreased and maintained at a certain level; the difference between the two groups was statistically significant (P < 0.05).

Conclusions

Distraction osteogenesis of femur can significantly increase PBMSCs in SD rats and participate in the process of bone formation.

The Use of Peripheral Blood-Derived Stem Cells for Cartilage Repair and Regeneration In Vivo: A Review

Background

Peripheral blood (PB) is a potential source of chondrogenic progenitor cells that can be used for cartilage repair and regeneration. However, the cell types, isolation and implantation methods, seeding dosage, ultimate therapeutic effect, and in vivo safety remain unclear.

Methods

PubMed, Embase, and the Web of Science databases were systematically searched for relevant reports published from January 1990 to December 2019. Original articles that used PB as a source of stem cells to repair cartilage in vivo were selected for analysis.

Results

A total of 18 studies were included. Eight human studies used autologous nonculture-expanded PB-derived stem cells (PBSCs) as seed cells with the blood cell separation isolation method, and 10 animal studies used autologous, allogenic or xenogeneic culture-expanded PB-derived mesenchymal stem cells (PB-MSCs), or nonculture-expanded PBSCs as seed cells. Four human and three animal studies surgically implanted cells, while the remaining studies implanted cells by single or repeated intra-articular injections. 121 of 130 patients (in 8 human clinical studies), and 230 of 278 animals (in 6 veterinary clinical studies) using PBSCs for cartilage repair achieved significant clinical improvement. All reviewed articles indicated that using PB as a source of seed cells enhances cartilage repair in vivo without serious adverse events.

Conclusion

Autologous nonculture-expanded PBSCs are currently the most commonly used cells among all stem cell types derived from PB. Allogeneic, autologous, and xenogeneic PB-MSCs are more widely used in animal studies and are potential seed cell types for future applications. Improving the mobilization and purification technology, and shortening the culture cycle of culture-expanded PB-MSCs will obviously promote the researchers' interest. The use of PBSCs for cartilage repair and regeneration in vivo are safe. PBSCs considerably warrant further investigations due to their superiority and safety in clinical settings and positive effects despite limited evidence in humans.

Intra-articular Injection of Kartogenin-Incorporated Thermogel Enhancing Osteoarthritis Treatment

To provide a vehicle for sustained release of cartilage-protective agent for the potential application of osteoarthritis (OA) treatment, we developed a kartogenin (KGN)-incorporated thermogel for intra-articular injection. We fabricated a poly(lactide-co-glycolide)-block-poly(ethylene glycol)-block-poly(lactide-co-glycolide) (PLGA–PEG–PLGA) thermogel as a KGN carrier for IA injection. OA chondrocytes were cultured in thermogel with or with no KGN to investigate the effect of KGN thermogel on cartilage matrix. The in vivo effect of KGN thermogel on OA was examined in a rabbit OA model. The KGN thermogel showed a sustained in vitro release of KGN for 3 weeks. OA chondrocytes proliferated well both in thermogel and KGN thermogel. In addition, OA chondrocytes produced higher amount of [type 2 collagen (COL-2) and glycosaminoglycan (GAG)], as well as lower level of matrix metalloproteinase 13 (MMP-13) in KGN thermogel that those in thermogel with no addition of KGN. The gene analysis supported that KGN thermogel enhanced expression of hyaline-cartilage specific genes Col 2 and AGC, and inhibited the expression of MMP-13. Compared with intra-articular injection of saline or thermogel containing no KGN, KGN thermogel can enhance cartilage regeneration and inhibit joint inflammation of arthritic knees in a rabbit ACLT-induced OA model at 3 weeks after the injection. Therefore, the KGN-incorporated PLGA–PEG–PLGA thermogel may provide a novel treatment modality for OA treatment with IA injection.

Effects of Intermittent Parathyroid Hormone 1-34 Administration on Circulating Mesenchymal Stem Cells in Postmenopausal Osteoporotic Women

BACKGROUND Intermittent parathyroid hormone (PTH) 1-34 administration stimulates osteogenesis and increases bone marrow mesenchymal stem cell (MSC) density; however, its effect on the circulating MSCs is unknown. This study aimed to examine the effect of intermittent PTH 1-34 administration on circulating MSCs in the peripheral blood of postmenopausal osteoporotic women. MATERIAL AND METHODS Fifty-four postmenopausal osteoporotic women at high risk of fracture were enrolled and administered either teriparatide (PTH 1-34) or alendronate for 12 months. Whole blood samples were obtained at baseline, 1, 3, 6, and 12 months after initiation of treatment. Flow cytometry analyses were performed to identify circulating MSCs (CD73+, CD90+, CD105+, CD34-, and CD45-). Serum markers of bone formation, bone resorption, as well as bone mineral density (BMD) were serially measured. Circulating MSCs were isolated from peripheral blood of teriparatide treated women and cultured in osteogenic medium to examine their osteogenic differentiation potential. RESULTS Teriparatide treatment increased circulating MSCs to 141±96% (P<0.001) by month 1, persisting until month 12; this increase was positively associated with increases in bone formation and bone resorption biomarkers (at month 6) and spine BMD (at month 12). Furthermore, intermittent PTH 1-34 administration promoted in vitro osteogenic differentiation of circulating MSCs, evident from increased alkaline phosphatase (ALP) activity, ALP-expressing cell density, calcium deposition, and Runx-2, OSX, COL 1a1, and osteocalcin mRNA upregulation. CONCLUSIONS Intermittent PTH 1-34 administration increased circulating MSC density in women with postmenopausal osteoporosis and enhanced in vitro osteogenic differentiation potential of these cells.

Intra-articular Mesenchymal Stem Cell Therapy for the Human Joint: A Systematic Review

BACKGROUND

Stem cell therapy is emerging as a potential treatment of osteoarthritis (OA) and chondral defects (CDs). However, there is a great deal of heterogeneity in the literature. The indications for stem cell use, the ideal tissue source, and the preferred outcome measures for stem cell-based treatments have yet to be determined.

PURPOSE

To provide clinicians with a comprehensive overview of the entire body of the current human literature investigating the safety and efficacy of intra-articular mesenchymal stem cell (MSC) therapy in all joints.

METHODS

To provide a comprehensive overview of the current literature, all clinical studies investigating the safety and efficacy of intra-articular MSC therapy were included. PubMed, MEDLINE, and Cochrane Library databases were searched for published human clinical trials involving the use of MSCs for the treatment of OA and CDs in all joints. A total of 3867 publications were screened.

RESULTS

Twenty-eight studies met the criteria to be included in this review. Fourteen studies treating osteoarthritis and 14 studies treating focal chondral defects were included. MSCs originating from bone marrow (13), adipose tissue (12), synovial tissue (2), or peripheral blood (2) were administered to 584 distinct individuals. MSCs were administered into the knee (523 knees), foot/ankle (61), and hip (5). The mean follow-up time was 24.4 months after MSC therapy. All studies reported improvement from baseline in at least 1 clinical outcome measure, and no study reported major adverse events attributable to MSC therapy.

DISCUSSION

The studies included in this review suggest that intra-articular MSC therapy is safe. While clinical and, in some cases, radiological improvements were reported for both OA and CD trials, the overall quality of the literature was poor, and heterogeneity and lack of reproducibility limit firm conclusions regarding the efficacy of these treatments.

CONCLUSION

This review provides strong evidence that autologous intra-articular MSC therapy is safe, with generally positive clinical outcomes.

[Operative treatment of cartilage lesions]

Cartilage damage is often associated with pain, reduced quality of life and decreased physical performance. In addition, even small cartilage lesions can lead to osteoarthritis. Since young active people are particularly affected, the correct treatment of cartilage damage plays an important role. Operative treatment includes bone marrow-stimulating procedures with or without a matrix, cell-based procedures and osteochondral graft transplantation. The choice of the best procedure depends on the localization, the size and the extent of the cartilage damage. In addition, especially in the treatment of cartilage damage to the lower limbs, the leg axis and loading relationships should be taken into account and possibly treated as well as additional joint instabilities. The following article gives an overview of the available surgical treatment possibilities as well as the correct indications and implementation. It also gives a brief projection of possible further treatment options associated with stem cells.

Microgrooved-surface topography enhances cellular division and proliferation of mouse bone marrow-derived mesenchymal stem cells

Mesenchymal stem cells’ (MSCs) fate is largely determined by the various topographical features and a range of extracellular matrix (ECM) components present in their niches. Apart from maintaining structural stability, they regulate cell morphology, division, proliferation, migration and differentiation among others. Traditional MSC cultures, which are mainly based on two-dimensional smooth surfaces of culture dishes and plates, do not provide topographical cues similar to in vivo three-dimensional niches, impacting various cellular processes. Therefore, we culture the mouse bone marrow-derived MSCs on microgrooved bearing surface, partially mimicking in vivo reticulated niche, to study its effect on morphology, pluripotency factor-associated stemness, cell division and rate of proliferation. Following culture, morphological features, and MSC-specific marker gene expression, such as CD29, CD44, Sca-1 along with HSC (Haematopoietic stem cell)-specific markers like CD34, CD45, CD11b were evaluated by microscopy and immunophenotyping, respectively. HSC is another type of bone marrow stem cell population, which concertedly interacts with MSC during various functions, including haematopoiesis. In addition, mesenchymal stem cells were further analyzed for gene expression of pluripotency-associated transcription factors such as Oct3/4, Sox-2, Nanog and Myc, as well as differentiated into adipocytes, osteocytes and chondrocytes. Our results show that microgrooved surface-cultured mesenchymal stem cells (MMSCs) expressed higher levels of expected cell surface and pluripotency-associated markers and proliferated more rapidly (2–3×fold) with higher percentage of cells in S/G2-M-phase, consequently giving rise to higher cell yield compared to standard culture flask-grown cells (MSCs), taken as control. Furthermore, both MSCs and MMSCs showed considerable accumulation of intracellular lipid-droplets, higher alkaline phosphatase activity and secretion of extracellular matrix that are characteristics of adipogenesis, osteogenesis and chondrogenesis, respectively.

Programmable cells of monocytic origin as a source of osteochondroprogenitors: Effect of growth factors on osteogenic differentiation

We have demonstrated previously that peripheral blood monocytes can be converted in vitro to a multipotent stem cell-like cell termed programmable cell of monocytic origin (PCMO) and subsequently into cells with chondrocyte-like phenotype. Here, we investigated whether PCMO could also be differentiated into osteoblast-like cells using growth factors with known osteoinductive potency. Following stimulation with BMP-2, BMP-7, IGF-1 or TGF-β1 for 7 and 14 days, PCMOs were analyzed for mRNA expression of collagen types I and V, alkaline phosphatase, osteocalcin, runt-related transcription factor-2 (Runx2) and Osterix (Osx) by quantitative RT-PCR (qPCR) and the levels of collagen I in culture supernatants by ELISA. The expression of osteoblastic markers was evident, albeit at a different extent in cultures of PCMOs after treatment with the above-mentioned growth factors. Culture supernatants from PCMOs stimulated for 6-10 days with BMP-2, BMP-7, IGF-1 or TGF-β1 contained high levels of collagen type I, together with earlier data indicating synthesis and proper secretion. The findings suggest that PCMOs can transform into cells that are phenotypically similar to osteoblasts and identify these cells as osteochondroprogenitors. The possibility of differentiating PCMOs from peripheral blood in sizable quantities could be a novel way to obtain autologous bone-like substitutes without donor-site morbidity.

Avoidance of Total Knee Arthroplasty in Early Osteoarthritis of the Knee with Intra-Articular Implantation of Autologous Activated Peripheral Blood Stem Cells versus Hyaluronic Acid: A Randomized Controlled Trial with Differential Effects of Growth Factor Addition

In this randomized controlled trial, in early osteoarthritis (OA) that failed conservative intervention, the need for total knee arthroplasty (TKA) and WOMAC scores were evaluated, following a combination of arthroscopic microdrilling mesenchymal cell stimulation (MCS) and repeated intra-articular (IA) autologous activated peripheral blood stem cells (AAPBSCs) with growth factor addition (GFA) and hyaluronic acid (HA) versus IA-HA alone. Leukapheresis-harvested AAPBSCs were administered as three weekly IA injections combined with HA and GFA (platelet-rich plasma [PRP] and granulocyte colony-stimulating factor [hG-CSF]) and MCS in group 1 and in group 2 but without hG-CSF while group 3 received IA-HA alone. Each group of 20 patients was evaluated at baseline and at 1, 6, and, 12 months. At 12 months, all patients in the AAPBSC groups were surgical intervention free compared to three patients needing TKA in group 3 (p < 0.033). Total WOMAC scores showed statistically significant improvements at 6 and 12 months for the AAPBSC groups versus controls. There were no notable adverse events. We have shown avoidance of TKA in the AAPBSC groups at 12 months and potent, early, and sustained symptom alleviation through GFA versus HA alone. Differential effects of hG-CSF were noted with an earlier onset of symptom alleviation throughout.

Chondrogenic Potential of Peripheral Blood Derived Mesenchymal Stem Cells Seeded on Demineralized Cancellous Bone Scaffolds

As a cell source with large quantity and easy access, peripheral blood mesenchymal stem cells (PBMSCs) were isolated and seeded in porcine demineralized cancellous bone (DCB) scaffolds, cultured in chondrogenic medium and evaluated for in vitro chondrogenesis. Bone marrow MSCs (BMMSCs) and articular cartilage chondrocytes (ACCs) underwent the same process as controls. The morphology, viability and proliferation of PBMSCs in DCB scaffolds were similar to those of BMMSCs and ACCs. PBMSCs and BMMSCs showed similar chondrogenesis potential with consistent production of COL 2 and SOX 9 protein and increased COL 2 and AGC mRNA expressions at week 3 but the COL 2 protein production was still less than that of ACCs. Minimal increase of hypertrophic markers was found in all groups. Relatively higher ALP and lower COL 10 mRNA expressions were found in both MSCs groups at week 3 than that in ACCs, whereas no significant difference of COL 1 and SOX 9 mRNA and MMP 13 protein was found among all groups. To conclude, PBMSCs shared similar proliferation and chondrogenic potential with BMMSCs in DCB scaffolds and could be an alternative to BMMSCs for cartilage tissue engineering. Further optimization of chondrogenesis system is needed regardless of the promising results.