Cell therapy for post-traumatic hip osteonecrosis in young patients.

PURPOSE: To investigate the effects of mesenchymal stem cells injections for treatment of post-traumatic osteonecrosis of the femoral head. METHODS: A total of 46 patients were eligible and enrolled in the study. Twenty-three patients were treated with cell therapy and 23 patients with hip arthroplasty (control group). During a minimum follow-up duration of 10years, radiographs were used to evaluate the radiological results, and the Harris Hip Score (HHS) and visual analog scale were chosen to assess the clinical results. RESULTS: For the cell therapy group, the product obtained by bone marrow aspiration in the iliac crest before concentration had a mean value of 2480 MSCs/mL (range 730 to 3800). The concentration product was containing average 9300 MSCs/mL (range 3930 to 19,800). At the most recent follow-up (average 15years after the first surgery, range 10 to 20years), among the 23 hips treated with cell therapy (concentrate bone marrow), 6 hips (26%) had collapsed and had required total hip arthroplasty (THA) without revision. Among the 23 hips treated with a primary THA, 7 (30.4%) had required one revision (second THA) at a mean follow-up of 6years (range 1 to 12years); two of these 7 hips had a re-revision; principal causes of revision were recurrent dislocations (3 cases) aseptic loosening (3 revisions) and infection (1 revision). As consequence, we observed significant (P<0.01) better survival time before revision for the cell therapy group. Better results with cell therapy were obtained for treatment at early stages before collapse. CONCLUSION: The present study has demonstrated encouraging effects of cell therapy in early post-traumatic hip osteonecrosis and provides another choice for treatment in early stages I to II.

Cell therapy for posttraumatic shoulder osteonecrosis.

PURPOSE: This study compared the clinical and radiological results of bone marrow mesenchymal stem cell implantation with traditional simple core decompression (CD) using a matched pair case-control design for osteonecrosis of the humeral head (ONHH) after fracture of the proximal humerus. PATIENTS: We retrospectively reviewed 64 patients who had surgery for ONHH. Thirty patients had been treated with cell therapy between 2010 and October 2015, with 18 patients at pre-collapse stage (8 stages-I, 10 stages-II), and 12 patients at post-collapse stages (7 stages-III and 5 stages-IV). Using a matched pair case-control design, these 30 study patients were compared to 34 other patients who were treated with simple core decompression (CD) without cells (control group). METHODS: The cell therapy group was treated with percutaneous mesenchymal cell (MSCs) injection obtained from bone marrow (BM) concentration. During a mean follow-up duration of 7years (5 to 10years), radiographs performed each year were used to evaluate the radiological results; the Constant score and visual analogue scale were chosen to assess the clinical results. We assessed stage progression, collapse and arthroplasty conversion rate. Survivor rate analysis was performed using these parameters as the primary endpoints. RESULTS: Among the 30 shoulders included in the cell therapy group, three (10%) humeral heads had collapsed at the most recent follow-up, versus 25 (74%) in 34 shoulders after simple core decompression (P<0.0001). As consequence, we observed statistically significant difference (P=0.0001) in the humeral head survival (absence of arthroplasty conversion) rate at the end time point between the cell therapy group (93% survival) and simple core decompression (26% survival). Better results were obtained for early stages (stages I and II) osteonecrosis without collapse at baseline. CONCLUSION: Core decompression with cell therapy was a safe and effective procedure for treatment in the pre-collapse stages of posttraumatic shoulder osteonecrosis and improved the outcome of the disease as compared with simple core decompression without cells.

Bone marrow mesenchymal stem cells stabilize already-formed aortic aneurysms more efficiently than vascular smooth muscle cells in a rat model.

PURPOSE: Abdominal aortic aneurysms (AAAs) expand because of aortic wall destruction. Enrichment in Vascular Smooth Muscle Cells (VSMCs) stabilizes expanding AAAs in rats. Mesenchymal Stem Cells (MSCs) can differentiate into VSMCs. We have tested the hypothesis that bone marrow-derived MSCs (BM-MSCs) stabilizes AAAs in a rat model. MATERIAL AND METHODS: Rat Fischer 344 BM-MSCs were isolated by plastic adhesion and seeded endovascularly in experimental AAAs using xenograft obtained from guinea pig. Culture medium without cells was used as control group. The main criteria was the variation of the aortic diameter at one week and four weeks. We evaluated the impact of cells seeding on inflammatory response by immunohistochemistry combined with RT-PCR on MMP9 and TIMP1 at one week. We evaluated the healing process by immunohistochemistry at 4 weeks. RESULTS: The endovascular seeding of BM-MSCs decreased AAA diameter expansion more powerfully than VSMCs or culture medium infusion (6.5% ± 9.7, 25.5% ± 17.2 and 53.4% ± 14.4; p = .007, respectively). This result was sustained at 4 weeks. BM-MSCs decreased expression of MMP-9 and infiltration by macrophages (4.7 ± 2.3 vs. 14.6 ± 6.4 mm(2) respectively; p = .015), increased Tissue Inhibitor Metallo Proteinase-1 (TIMP-1), compared to culture medium infusion. BM-MSCs induced formation of a neo-aortic tissue rich in SM-alpha active positive cells (22.2 ± 2.7 vs. 115.6 ± 30.4 cells/surface units, p = .007) surrounded by a dense collagen and elastin network covered by luminal endothelial cells. CONCLUSIONS: We have shown in this rat model of AAA that BM-MSCs exert a specialized function in arterial regeneration that transcends that of mature mesenchymal cells. Our observation identifies a population of cells easy to isolate and to expand for therapeutic interventions based on catheter-driven cell therapy.

Cell Colonization Ability of a Commercialized Large Porous Alveolar Scaffold.

The use of filling biomaterials or tissue-engineered large bone implant-coupling biocompatible materials and human bone marrow mesenchymal stromal cells seems to be a promising approach to treat critical-sized bone defects. However, the cellular seeding onto and into large porous scaffolds still remains challenging since this process highly depends on the porous microstructure. Indeed, the cells may mainly colonize the periphery of the scaffold, leaving its volume almost free of cells. In this study, we carry out an in vitro study to analyze the ability of a commercialized scaffold to be in vivo colonized by cells. We investigate the influence of various physical parameters on the seeding efficiency of a perfusion seeding protocol using large manufactured bone substitutes. The present study shows that the velocity of the perfusion fluid and the initial cell density seem to impact the seeding results and to have a negative effect on the cellular viability, whereas the duration of the fluid perfusion and the nature of the flow (steady versus pulsed) did not show any influence on either the fraction of seeded cells or the cellular viability rate. However, the cellular repartition after seeding remains highly heterogeneous.

Do minitransplants have minicosts? A cost comparison between myeloablative and nonmyeloablative allogeneic stem cell transplant in patients with acute myeloid leukemia.

Allogeneic hematopoietic stem cell transplantation (SCT) is a widely used, cost-intensive procedure. Although pretransplant nonmyeloablative (NMA) or reduced-intensity conditioning regimens appear very promising, prospective studies comparing this approach with the conventional myeloablative (MA) approach in specific hematologic diseases are necessary, especially in patients in whom the conventional approach is not contraindicated. Cost may be an important factor in the decision-making process. We compared the costs of MA and NMA transplants in patients with acute myeloid leukemia (AML). We estimated 1-year resource utilization in 12 consecutive MA patients (median age: 39 years) and in 11 consecutive NMA patients (median age: 58 years) who underwent HLA-identical sibling SCT for AML. Resources care expenses were valued using the average daily rate for personnel costs, supplies, and room costs. Other data were directly collected from the patients' charts. Despite a trend for lower costs in NMA patients during the first 6 months, costs during the 6-12-month period were significantly higher after NMA due to late complications and readmissions (P=0.03). Finally, mean 1-year costs were not different in MA and NMA patients (P=0.75). Prospective studies comparing conventional and NMA approaches in homogeneous populations should include economic items.

Percutaneous autologous bone-marrow grafting for nonunions. Influence of the number and concentration of progenitor cells.

BACKGROUND: Bone marrow aspirated from the iliac crest contains progenitor cells that can be used to obtain bone-healing of nonunions. However, there is little available information regarding the number and concentration of these cells that are necessary to obtain bone repair. The purpose of this study was to evaluate the number and concentration of progenitor cells that were transplanted for the treatment of nonunion, the callus volume obtained after the transplantation, and the clinical healing rate. METHODS: Marrow was aspirated from both anterior iliac crests, concentrated on a cell separator, and then injected into sixty noninfected atrophic nonunions of the tibia. Each nonunion received a relatively constant volume of 20 cm(3) of concentrated bone marrow. The number of progenitor cells that was transplanted was estimated by counting the fibroblast colony-forming units. The volume of mineralized bone formation was determined by comparing preoperative computerized tomography scans with scans performed four months following the injection. RESULTS: The aspirates contained an average (and standard deviation) of 612 +/- 134 progenitors/cm(3) (range, 12 to 1224 progenitors/cm(3)) before concentration and an average of 2579 +/- 1121 progenitors/cm(3) (range, 60 to 6120 progenitors/cm(3)) after concentration. An average total of 51 x 10(3) fibroblast colony-forming units was injected into each nonunion. Bone union was obtained in fifty-three patients, and the bone marrow that had been injected into the nonunions of those patients contained >1500 progenitors/cm(3) and an average total of 54,962 +/- 17,431 progenitors. The concentration (634 +/- 187 progenitors/cm(3)) and the total number (19,324 +/- 6843) of progenitors injected into the nonunion sites of the seven patients in whom bone union was not obtained were both significantly lower (p = 0.001 and p < 0.01, respectively) than those in the patients who obtained bone union. The volume of the mineralized callus measured at four months on the computerized tomography scans of the patients who had union ranged from 0.8 to 5.3 cm(3) (mean, 3.1 cm(3)). There was a positive correlation between the volume of mineralized callus at four months and the number (p = 0.04) and concentration (p = 0.01) of fibroblast colony-forming units in the graft. There was a negative correlation between the time needed to obtain union and the concentration of fibroblast colony-forming units in the graft (p = 0.04). CONCLUSIONS: Percutaneous autologous bone-marrow grafting is an effective and safe method for the treatment of an atrophic tibial diaphyseal nonunion. However, its efficacy appears to be related to the number of progenitors in the graft, and the number of progenitors available in bone marrow aspirated from the iliac crest appears to be less than optimal in the absence of concentration.

Adenoviral transduction of human 'clinical grade' immature dendritic cells enhances costimulatory molecule expression and T-cell stimulatory capacity.

The therapeutic use of dendritic cells (DC) in antigen-specific anti-tumor vaccines, requires sufficient numbers of functional DC, the preparation of which should comply with the code of Good Manufacturing Practice. In addition, the expression of tumor specific antigen should be possible in these DC. As a preclinical step, the method reported here was developed in healthy volunteers. Monocytes (Mo) were isolated by leukapheresis from 12 donors, purified by elutriation and then cultured for 6 days in sealed bags in AIM-V serum free medium with granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin-13 (IL-13). Between 6x10(8) and 1x10(9) immature DC (iDC) could be differentiated from one leukapheresis. Cells displayed a characteristic iDC phenotype (CD1a(+), CD14(-), CD80(+), CD86(+), HLA DR(+), CD83(-)), and had potent allogeneic and antigen dependent autologous T cell-stimulatory capacity. Moreover, iDC could be further differentiated into mature DC by CD40 ligation as assessed by CD83 expression and the upregulation of HLA-DR and costimulatory molecules. After infection with a recombinant adenovirus encoding for beta-galactosidase (betaGal), 50% to 80% of iDC expressed betaGal without toxicity. Adenovirus infection increased the expression of both costimulatory molecules and CD83, and also increased allogeneic stimulatory capacity. Thus, the method developed here allows us to use large numbers of functional iDC as will be required for therapeutic uses in man. These DC can express a transgenic protein.

Oligoclonal T-cells in blood and target tissues of patients with anti-Hu syndrome.

T-cell clones of unknown significance (TCUS), assessed by monoclonal or oligoclonal T-cell patterns in PCR-DGGE, were detected in blood of 7/9 patients with anti-Hu syndrome. Clonal patterns were also detected in 2/2 neoplastic lymph nodes, and in 2/2 inflamed dorsal root ganglia from three patients. Only some T-cell clones found in target tissues were also detected in blood or non-target tissues, and likely corresponded to TCUS. In one patient, an identical T-cell clone was found in both neoplastic lymph node tissue and dorsal root ganglia, but not in blood. Dorsal root-infiltrating lymphocytes were cytotoxic CD8(+) TIA-1(+) T-cells. They were often found in close contact to sensory neurons, most of which expressed MHC-1. Taken together, these data support a direct effector role of cytotoxic CD8(+) T-cells, the same clones being likely operative in sensory neuron damage and immune-mediated tumor growth control.

Vav and SLP-76 recruitment by cross-linking of FcgammaRIIa1 in promyelocytic HL-60 cells.

The signaling events induced upon cross-linking of the human FcgammaRIIa1 (CD32) which contains an immune receptor tyrosine-based activation motif (ITAM) in its intracellular region, were investigated in the promyelocytic HL-60 cells. It is shown here that the FcgammaRIIa1 engagement recruits the Ras pathway in these cells, as evidenced by the tyrosine-phosphorylation of the Shc adaptator protein and of the extracellular signal-regulated kinase 2 (ERK2). However, p95vav, a molecule able to interact with Rac-1 and to regulate cytoskeletal reorganization, was also found to be phosphorylated. In addition, co-immunoprecipitation experiments demonstrated that Vav is associated with SLP-76 upon FcgammaRIIa1 activation. A strong phosphorylation of p120cbl was also observed. The phosphorylation of molecules such as p95vav, SLP-76 and p120cbl suggests that FcgammaRIIa1 triggering also activates signaling pathways other than the Ras pathway.

Fc receptors as targets for immunotherapy.

Human membrane and soluble Fc epsilon receptors (Fc epsilon RI, Fc epsilon RII/CD23) and Fc gamma receptors (Fc gamma RI/CD64, Fc gamma RII/CD32, Fc gamma RIII/CD16) have been implicated in a number of diseases. Their functional roles such as capture and clearance of immune complexes, antibody-dependent cell cytotoxicity, or cytokine or inflammatory mediator release, make them potential targets for immuno-intervention. In the present review, we will describe how membrane and soluble human Fc epsilon R and Fc gamma R have been already used as targets/tools for immuno-interventions by using monoclonal and bispecific engineered antibodies. Some therapeutic uses of these molecules both in cancer, infectious, and auto-immune diseases are presented.

A new set of monoclonal antibodies against human Fc gamma RII (CD32) and Fc gamma RIII (CD16): characterization and use in various assays.

Four mouse anti-human Fc gamma RII (CD32) (6C4, 2B2, 3D3, 93.4) (IgG1, kappa) and one anti-human Fc gamma RIII (CD16) (7.5.4) IgG1, kappa) MAbs were raised. An in vitro switch variant, 7.5.4Sw50 (IgG2b, kappa), was also derived from the 7.5.4 MAb. 6C4, 2B2, and 3D3 MAbs bind both Fc gamma RIIa and Fc gamma RIIb isoforms. Two of them (6C4 and 2B2 MAbs) allow a complete blockade of the binding of immune complexes to Fc gamma RII. All three MAbs immunoprecipitate the receptor and bind both its glycosylated and nonglycosylated forms. The fourth anti Fc gamma RII MAb, 93.4, directed against the intracellular region of Fc gamma RIIa1/2, allows its detection by Western blotting only when it is not phosphorylated. The 7.5.4 MAb binds both Fc gamma RIIIa and Fc gamma RIIIb, can be used in Western blotting and does not inhibit aggregated IgG binding. ELISA using IV.3 (anti-Fc gamma RIIa1/2)/6C4 and 3G8 (anti-Fc gamma RIIIa/b)/7.5.4Sw50 MAb pairs make it possible to detect soluble Fc gamma RIIa1/2 and Fc gamma RIII, with a sensitivity of 200 pg/mL and 1 ng/mL, respectively. Surface plasmon resonance analyses indicated that the KD of two of the three anti-Fc gamma RII and of the anti-Fc gamma RIII are in the same order of magnitude (6C4: 0.78 nM, 2B2: 0.28 nM, 7.5.4: 0.47 nM). The anti-Fc gamma RII 3D3 MAb exhibits an off-rate constant higher than the 6C4 and 2B2 MAbs and a KD of 2.19 nM.

[Cord blood banking: from theory to an application]. / La collecte de sang placentaire: du concept à la réalité.

Cord blood units are now routinely used as an alternative source of haematopoietic stem cells from unrelated donors for allogeneic transplantation. In France, cord blood units are collected in a network of more than 70 maternity hospitals in relationship with 11 public cord blood banks part of the Réseau Français de Sang Placentaire. Unrelated cord blood unit donation is an altruistic act, anonymous and free. Donors are selected on medical criteria. Then, only cord blood unit containing more than 100 × 10(7) total nucleated cells and more than 1.8 × 10(6) CD34+ cells are cryopreserved according to Réseau Français de Sang Placentaire recommendations. Cord blood units qualification will be completed by viral and functional testings and the clinical outcome of the newborn child 6 weeks after the collection. Since the last 5 years, cord blood banking growing in France in order to enhance the French registry of volunteer donors by increasing both the number and diversity of the donors listed and make available cord blood banking for transplantation.

[Mesenchymal stromal cells: Biological properties and clinical prospects]. / Cellules stromales mésenchymateuses : propriétés biologiques et perspectives thérapeutiques.

Mesenchymal stromal cells are defined as non-hematopoietic progenitors characterised by their adherence to plastic in culture, their expression of non-specific markers and their differentiation potential into cells of mesodermic lineage. Resident in numerous tissues, mesenchymal stromal cells are now available from several sources, including both adult and foetal tissues. After their administration, mesenchymal stromal cells preferentially migrate to injured tissues. Mesenchymal stromal cells have therapeutic effects in numerous animal models of tissue injury by a mechanism not yet clearly understood. Mechanisms likely involved in repair can be the production of paracrine, anti-inflammatory and anti-apoptotic factors, as well as cell replacement by their differentiation potential. Mesenchymal stromal cells possess immunosuppressive properties on both innate and adaptative immunity in vitro and in animal models of autoimmunity. Currently their immunosuppressive properties allow testing of mesenchymal stromal cells in allogenic context, although this use requires further investigations. Mesenchymal stromal cells can be isolated and expanded in vitro in clinical grade conditions. They represent a promising candidate for the cellular therapy of diseases, such as acute myocardial infarction, diabetes, graft versus host disease or neurodegenerative diseases. Critical points including the standardization of production and long term toxicity have to be resolved before their large scale use in clinical conditions.

Percutaneous autologous bone-marrow grafting for nonunions. Surgical technique.

BACKGROUND: Bone marrow aspirated from the iliac crest contains progenitor cells that can be used to obtain bone-healing of nonunions. However, there is little available information regarding the number and concentration of these cells that are necessary to obtain bone repair. The purpose of this study was to evaluate the number and concentration of progenitor cells that were transplanted for the treatment of nonunion, the callus volume obtained after the transplantation, and the clinical healing rate. METHODS: Marrow was aspirated from both anterior iliac crests, concentrated on a cell separator, and then injected into sixty noninfected atrophic nonunions of the tibia. Each nonunion received a relatively constant volume of 20 cm(3) of concentrated bone marrow. The number of progenitor cells that was transplanted was estimated by counting the fibroblast colony-forming units. The volume of mineralized bone formation was determined by comparing preoperative computerized tomography scans with scans performed four months following the injection. RESULTS: The aspirates contained an average (and standard deviation) of 612 +/- 134 progenitors/cm(3) (range, 12 to 1224 progenitors/cm(3)) before concentration and an average of 2579 +/- 1121 progenitors/cm(3) (range, 60 to 6120 progenitors/cm(3)) after concentration. An average total of 51 x 10(3) fibroblast colony-forming units was injected into each nonunion. Bone union was obtained in fifty-three patients, and the bone marrow that had been injected into the nonunions of those patients contained >1500 progenitors/cm(3) and an average total of 54,962 +/- 17,431 progenitors. The concentration (634 +/- 187 progenitors/cm(3)) and the total number (19,324 +/- 6843) of progenitors injected into the nonunion sites of the seven patients in whom bone union was not obtained were both significantly lower (p = 0.001 and p < 0.01, respectively) than those in the patients who obtained bone union. The volume of the mineralized callus measured at four months on the computerized tomography scans of the patients who had union ranged from 0.8 to 5.3 cm(3) (mean, 3.1 cm(3)). There was a positive correlation between the volume of mineralized callus at four months and the number (p = 0.04) and concentration (p = 0.01) of fibroblast colony-forming units in the graft. There was a negative correlation between the time needed to obtain union and the concentration of fibroblast colony-forming units in the graft (p = 0.04). CONCLUSIONS: Percutaneous autologous bone-marrow grafting is an effective and safe method for the treatment of an atrophic tibial diaphyseal nonunion. However, its efficacy appears to be related to the number of progenitors in the graft, and the number of progenitors available in bone marrow aspirated from the iliac crest appears to be less than optimal in the absence of concentration.

Specific antibodies modulate the interactions of adenovirus type 5 with dendritic cells.

Adenovirus type 5 (Ad5) is able to induce an efficient CD8+ T lymphocyte (CTL) response against a transgene product, a property thought to be linked to its ability to transduce dendritic cells (DCs). Little, however, is known about the capacity of Ad5 to interact with DCs in the presence of specific antibodies, although most people test positive for antibodies directed against Ad5. In the present study, we found that in the presence of Ad5 antibodies, a large fraction of Ad5 binds very efficiently to DCs, and that this binding is FcgammaRII/FcgammaRIII dependent. Nevertheless, in the presence of high levels of antibodies against the whole virion, Ad5 entry was inhibited. Increased binding led to increased entry in DCs in the presence of fiber-specific antibodies or in the presence of low amounts of a whole antiserum raised against whole virions, showing that the relative concentration of antibodies directed against fiber and penton base plays a major role in entry efficacy. Nevertheless, mice previously immunized with virions or purified fiber developed a lower transgene-specific CD8+ T cell response than naive mice, although their serum appeared to increase virus entry into DCs in vitro.

Multiple co-stimulatory signals are required for triggering proliferation of T cells from human secondary lymphoid tissue.

Vaccine-based therapies are being developed for a variety of cancers and their efficacy will be determined by their ability to stimulate T cells in the secondary lymphoid tissue. We found that T cells isolated from human secondary lymphoid organs (LT-T), in contrast to peripheral blood T cells (PB-T) are hyporesponsive to cross-linked anti-CD3 mAb (CD3c) even in the presence of exogenous IL-2. Using mAb to trigger CD2 and CD28 co-stimulatory molecules, we found that such dual co-stimulation of LT-T induces profound and sustained responses including CD25 expression, IL-2 secretion and proliferation. Different levels of co-stimulation produced a hierarchical pattern of responses in LT-T, which correlated with the degree of CD3-TCR down-regulation. Mature antigen-presenting cells (APC) restored the capacity of LT-T to proliferate to stimulation of the CD3-TCR complex. Blocking studies demonstrated that optimal proliferation was critically dependent on co-stimulation via CD2 and CD28 engaged by their ligands on the APC. Therefore, LT-T have increased co-stimulatory requirements as compared to PB-T, i.e. multiple co-stimulatory signals coupled to CD3-TCR triggering. Furthermore, LT-T were found to be dependent on APC for survival, in contrast to PB-T. Clearly, LT-T do not behave in a comparable way to PB-T and in vitro experiments assessing novel cancer vaccines should therefore use LT-T as the most appropriate population of responder T cells.