Bone Marrow Aspirate Concentrate and Expanded Stem Cell Applications in Orthopaedics

By Bentham Science Publishers

This reference presents insights into the development of bone marrow aspirate stem cell BMAC technology and the potential role of stem cell expansion in the regeneration of damaged and deficient musculoskeletal tissues. The book features valuable contri

• Language: English
• Publisher: Bentham Science Publishers
• Release date: Jun 6, 2018
• ISBN: 9781681086491

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USA.

Introduction

Mohamed A. Imam¹, *, Yasser Elsherbini², ³, Martyn Snow¹

¹ Department of Arthroscopy, The Royal Orthopaedic Hospital, Birmingham, UK

² Research and Development, OxCell, OX3 8ATOxford, UK

³ Institute of Biomedical Engineering, University of Oxford, OX3 7DQOxford, UK

Abstract

Mesenchymal Stem Cells (MSCs) have multipotent plasticity. They demonstrate the ability to differentiate into various cell types. These include bone, tendon, cartilage, muscles and nerve [1-6]. Subsequently, they can have a role in the coming era of medicine as they have the potential to contribute to the regeneration and reconstruction of different tissues, especially in musculoskeletal medicine. As yet, Bone marrow is regarded as the most attractive source of MSCs [7, 8] and for the last few years, numerous interventionists have employed unprocessed Bone Marrow Aspirate (BMA), to incite healing.

Keywords: Bone Marrow Aspirate Concentrate (BMAC), Expanded stem cells, MSCs.

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* Corresponding author Mohamed A. Imam: Department of Arthroscopy, The Royal Orthopaedic Hospital, Birmingham, UK; Tel: [phone]; Fax: [phone]; E-mail: [e-mail]

The concentration of MSCs in the marrow is known to be around 7-30 cells/million-nucleated cells [9]. To approach this matter, several etiquettes have emerged to increase the concentration of the nucleated cells to provide Bone Marrow Aspirate Concentrate (BMAC) with the aim that it would produce an adequate amount of MSCs required to produce efficacious conditions for healing and reconstruction [9, 10]. Hernigou et al. [11] reported that the effectiveness of BMAC depends on the concentration of progenitors cells. They examined the amount and density of these cells in BMA and BMAC taken from the iliac crest. The BMAC contained a mean of 2579 +/- 1121 compared with 612 +/- 134 cells/cm³ in the BMA cohort. They highlighted that Diminished array of progenitor cells is significantly associated with non-union (p < 0.01).

Hyer et al. [12] have recommended that the iliac crest had a higher mean density of bone forming progenitor cells, especially when compared with other localities. Enormous quantities of BMA are consequently needed when aspirating from the

tibia or calcaneus to produce a comparable amount of MSCs collected from the iliac bone. Variables like age, sex, smoking, and diabetes did not correlate with the osteoblastic progenitor cell concentration [12].

Hernigou et al. [13] have described the sector rule for harvesting marrow from the iliac crest. This was mainly dependant on their safety zones concept. The authors analysed 480 insertion locations carried out by six surgeons in 120 cases. They recognized raised peril of breaches in overweight patients and this risk is reduced when more experienced personal undertook the procedure. They recommended that the sector rule concept is a safe way for BMA harvesting. Hernigou et al. [14] in another investigation further recognized that the use of 10ml syringes to harvest BMA was better than using the 50ml ones.

The chief attention in using bone marrow aspirate is the decreased quantity of stem cells attained within it, as barely 0.001% of nucleated cells are real MSCs [4, 14, 15]. Various systems have been introduced to concentrate BMA to develop BMAC. These involve the employment of Ficoll density gradients laboratories and automated systems in the clinical context. Although these systems improve the quantity of MSCs, all do not significantly improve the proportion of MSCs to nucleated cells [9, 10, 15]. Centrifugation is the modern system of preference for the numerous commercially usable commodities utilized clinically, although comparing it to Platelet-rich plasma (PRP), there is a significant disparity in the definitive end outputs achieved. Fortier et al. [16], examined the ingredients of PRP and BMAC (Table 1); there are decreased platelets and elevated WBC’s in BMAC confirming that this is a distinct construct when compared with PRP with a distinct mechanism of action.

Table 1 Results of Cytological Analysis of Bone Marrow Aspirate and Bone Marrow Concentrate [16].

The notion of BMAC is to promote the regeneration of the nucleated cells from the marrow) while reducing the restoration of non-nucleated cells (e.g. RBCs). The precise mechanism of action of BMAC is still not fully appreciated. Conceivably, the concentration of MSCs within BMAC will produce a primary cell origin for reconstruction of the targeted tissue. Alternatively, or in addition to, the nucleated cells may deliver various cytokines and growth factors into the delivery site to orchestrate and direct host repair [16-20].

This book intends to explore the contemporary published clinical applications of BMAC and expanded stem cells and its effectiveness in managing different pathologies in musculoskeletal sciences.

CONSENT FOR PUBLICATION

Not applicable.

CONFLICT OF INTEREST

The authors declare no conflict of interest, financial or otherwise.

ACKNOWLEDGEMENTS

Declared none.

REFERENCES