Quantification and Comprehensive Analysis of Mesenchymal Stromal Cells in Bone Marrow Samples from Sickle Cell Disease Patients with Osteonecrosis.

The potential use of bone marrow mesenchymal stromal cells (BM-MSCs) for the treatment of osteonecrosis in sickle cell disease (SCD) patients is increasing. However, convenient BM-MSC quantification and functional property assays are critical factors for cell-based therapies yet to be optimized. This study was designed to quantify the MSC population in bone marrow (BM) samples from SCD patients with osteonecrosis (SCD group) and patients with osteoarticular complications not related to SCD (NS group), using flow cytometry for CD271+CD45-/low cell phenotype and CFU-F assay. We also compared expanded BM-MSC osteogenic differentiation, migration, and cytokine secretion potential between these groups. The mean total cell number, CFU-F count, and CD271+CD45-/low cells in BM mononuclear concentrate were significantly higher in SCD than in NS patients. A significant correlation between CD271+CD45-/low cell number and CFU-F counts was found in SCD (r = 0.7483; p = 0.0070) and NS (r = 0.7167; p = 0.0370) BM concentrates. An age-related quantitative reduction of CFU-F counts and CD271+CD45-/low cell number was noted. Furthermore, no significant differences in the morphology, replicative capacity, expression of surface markers, multidifferentiation potential, and secretion of cytokines were found in expanded BM-MSCs from SCD and NS groups after in vitro culturing. Collectively, this work provides important data for the suitable measurement and expansion of BM-MSC in support to advanced cell-based therapies for SCD patients with osteonecrosis.

Autologous stem cell-based therapy for sickle cell leg ulcer: a pilot study.

Recurrent chronic leg ulcers are among the most severe vasculopathic complications of sickle cell disease (SCD). Their treatment remains a challenge. Stem cell therapy with bone marrow mononuclear cells (BMMC) is a promising new therapeutic option for other forms of chronic ulcers. This prospective pilot study was performed to evaluate safety and feasibility of BMMC implantation in patients with SCD and chronic leg ulcers (SCLU). Ulcer closure, recurrence and local pain were evaluated. BMMC were successfully administered to 23 SCLU patients and no serious adverse events occurred. During the 6-month follow-up period, 91·3% of patients had improved ulcer pain compared with baseline and 29·2% of the treated ulcers achieved total healing. The frequency of progenitor stem cells (CD34CD45low and fibroblast colony-forming units) in BMMC was found to be significantly reduced in SCLU patients and compared to SCD patients without ulcers (P < 0·004 and P < 0·01, respectively). No relationship was observed between treatment outcome and the number of implanted BM progenitor stem cells. In conclusion, BMMC implantation is a feasible and safe procedure, showing favourable outcomes for the treatment of SCLU, and encouraging further controlled clinical trials.

Efficacy of autologous stem cell-based therapy for osteonecrosis of the femoral head in sickle cell disease: a five-year follow-up study.

INTRODUCTION: Stem cell therapy with bone marrow-derived mononuclear cells (BMMCs) is an option for improving joint function in osteonecrosis of the femoral head (ONFH). Bone marrow-derived mesenchymal stromal cell (MSC) numbers and their osteogenic differentiation are decreased in patients with ONFH. However, whether this decrease also extends to the early stages of ONFH in sickle cell disease (SCD) is still unclear. METHODS: We conducted a phase I/II, non-controlled study to determine efficacy and safety of BMMC implantation using a minimally invasive technique in SCD patients with ONFH. Eighty-nine patients were recruited and followed up for 60 months after surgery. Clinical and radiographic findings were assessed, and data were completed by in vitro analysis. RESULTS: At the final follow-up (60 months) there was a significant improvement in clinical joint symptoms and pain relief as measured by the Harris Hip Score (P = 0.0005). In addition, after the BMMC implantation procedure, radiographic assessment showed disease stabilization and only 3.7 % of the treated patients did not achieve a satisfactory clinical result. The amount of fibroblast colony-forming units was 28.2 ± 13.9 per 1 million BMMCs after concentration. Flow cytometry analysis showed a significantly higher number of hematopoietic stem/endothelial progenitor cell markers in concentrated BMMCs when compared with bone marrow aspirate, indicating an enrichment of these cell types. Isolated MSCs from SCD patients with pre-collapse ONFH maintained the replicative capacity without significant loss of their specific biomolecular characteristics, multi-differentiation potential, and osteogenic differentiation activities. Cytokines and growth factors (interleukin-8, transforming growth factor-beta, stromal cell-derived factor-1alpha and vascular endothelial growth factor) that mediate endogenous bone regeneration were also produced by expanded MSCs from SCD patients. CONCLUSION: The autologous BMMC implantation with a minimally invasive technique resulted in significant pain relief and halted the progression of early stages of ONFH in SCD patients. MSCs from SCD patients display biological properties that may add to the efficiency of surgical treatment in ONFH. In summary, our results indicate that infusion of BMMCs enriched with stem/progenitor cells is a safe and effective treatment for the early stages of ONFH in SCD patients. TRIAL REGISTRATION: ClinicalTrials.gov NCT02448121; registered 15 May 2015.

Tratamento da Osteonecrose da Cabeça Femoral com celulas progenitoras autólogas em anemia falciforme / Femoral Head Necrosis treatment with autologous stem cells in sickle cell disease

OBJETIVO: Avaliação da segurança e eficácia do uso de células progenitoras autólogas da medula óssea (CMMO) no tratamento da Osteonecrose da Cabeça Femoral (OCF) de pacientes portadores de anemia falciforme. MÉTODOS: Foram estudados 8 pacientes portadores de anemia falciforme, com OCF nos estágios I e II (classificação de Ficat e Arlet). As CMMO retiradas da crista ilíaca posterior foram concentradas e reinfundidas na área central da osteonecrose. Os principais parâmetros avaliados foram segurança, sintomas clínicos e progressão da doença, através da avaliação clínica (Harris Hip Score) e radiológica. RESULTADOS: A maior parte dos pacientes (7 em 8) referiu melhora dos sintomas após o tratamento. Não houve complicações durante o procedimento anestésico e cirúrgico. A medida do escore (Harris Hip Score) no pré-operatório foi 78,5 +/- 6,2 pontos, com aumento significativo destes valores no pós-operatório (98,3 +/- 2,5 pontos) (p< 0,001). As avaliações radiográficas e os parâmetros celulares foram favoráveis. CONCLUSÃO: O implante autólogo de CMMO parece ser seguro e eficaz no tratamento dos estágios iniciais da OCF em pacientes falciformes. Embora os resultados iniciais sejam promissores, sua interpretação é limitada pelo número de pacientes avaliados e o período curto de duração do seguimento pós-operatório. Necessita-se estender o grupo em estudo e os parâmetros celulares avaliados.

PURPOSE: To assess the efficacy and safety of autologous bone-marrow mononuclear cells (BMMC) implantation in necrotic lesions of the femoral head in patients with sickle cell disease. METHODS: We studied eight patients with stage-I or -II femoral head osteonecrosis according to the system by Ficat and Arlet. BMMCs were harvested and re-infused into the necrotic zone. The primary endpoints studied were safety, clinical symptoms and disease progression, these being assessed according to the Harris hip score (HHS) and to X-ray studies. RESULTS: After eight months, seven of the eight patients reported improvement from symptoms. There were no complications during anesthetic and surgery procedures. There was a significant postoperative increase in the HHS (98.3 +/- 2.5 points) compared to preoperative HHS (78.5 +/- 6.2 points) (p< 0.001). X-ray evaluation and cell parameters were found to be favorable. CONCLUSION: The autologous bone-marrow mononuclear cells implantation seems to be a safe and effective treatment for early stages of femoral head osteonecrosis in patients with sickle cell disease. Although promising, the interpretation of these early results is limited due to the small sample and to the short duration of follow-up. Further studies and advanced cellular assays are required to confirm the results.