Stricture prevention after extended circumferential endoscopic mucosal resection by injecting autologous keratinocytes in the sheep esophagus

During the past decades, endoscopic mucosal resection (EMR) has been developed to treat early intramucosal esophageal cancers and dysplastic Barrett's esophagus. The primary drawback of this method is severe postsurgical esophageal stricture formation. The purpose of this preclinical study was to assess strategies for prevention of this major complication by injecting autologous keratinocytes in the EMR mucosal defect in the sheep model.

High acceptance rate of hybrid allogeneic-autologous umbilical cord blood banking among actual and potential Swiss donors

Two competitive concepts of umbilical cord blood (UCB) banking are currently available: either allogeneic UCB is donated to a public bank or autologous cells are stored in a private bank. Allogeneic-autologous hybrid banking is a new concept that combines these two approaches. However, acceptance of hybrid UCB banking among potential donors is unknown to date.

Progenitor cell recruitment during individualized high-flow, very-large-volume apheresis for autologous transplantation improves collection efficiency

BACKGROUND: Individual adaptation of processed patient's blood volume (PBV) should reduce number and/or duration of autologous peripheral blood progenitor cell (PBPC) collections. STUDY DESIGN AND METHODS: The durations of leukapheresis procedures were adapted by means of an interim analysis of harvested CD34+ cells to obtain the intended yield of CD34+ within as few and/or short as possible leukapheresis procedures. Absolute efficiency (AE; CD34+/kg body weight) and relative efficiency (RE; total CD34+ yield of single apheresis/total number of preapheresis CD34+) were calculated, assuming an intraapheresis recruitment if RE was greater than 1, and a yield prediction models for adults was generated. RESULTS: A total of 196 adults required a total of 266 PBPC collections. The median AE was 7.99 x 10(6), and the median RE was 1.76. The prediction model for AE showed a satisfactory predictive value for preapheresis CD34+ only. The prediction model for RE also showed a low predictive value (R2 = 0.36). Twenty-eight children underwent 44 PBPC collections. The median AE was 12.13 x 10(6), and the median RE was 1.62. Major complications comprised bleeding episodes related to central venous catheters (n = 4) and severe thrombocytopenia of less than 10 x 10(9) per L (n = 16). CONCLUSION: A CD34+ interim analysis is a suitable tool for individual adaptation of the duration of leukapheresis. During leukapheresis, a substantial recruitment of CD34+ was observed, resulting in a RE of greater than 1 in more than 75 percent of patients. The upper limit of processed PBV showing an intraapheresis CD34+ recruitment is higher than in a standard large-volume leukapheresis. Therefore, a reduction of individually needed PBPC collections by means of a further escalation of the processed PBV seems possible.

Repair of superficial osteochondral defects with an autologous scaffold-free cartilage construct in a caprine model: implantation method and short-term results

OBJECTIVE: To compare four different implantation modalities for the repair of superficial osteochondral defects in a caprine model using autologous, scaffold-free, engineered cartilage constructs, and to describe the short-term outcome of successfully implanted constructs. METHODS: Scaffold-free, autologous cartilage constructs were implanted within superficial osteochondral defects created in the stifle joints of nine adult goats. The implants were distributed between four 6-mm-diameter superficial osteochondral defects created in the trochlea femoris and secured in the defect using a covering periosteal flap (PF) alone or in combination with adhesives (platelet-rich plasma (PRP) or fibrin), or using PRP alone. Eight weeks after implantation surgery, the animals were killed. The defect sites were excised and subjected to macroscopic and histopathologic analyses. RESULTS: At 8 weeks, implants that had been held in place exclusively with a PF were well integrated both laterally and basally. The repair tissue manifested an architecture similar to that of hyaline articular cartilage. However, most of the implants that had been glued in place in the absence of a PF were lost during the initial 4-week phase of restricted joint movement. The use of human fibrin glue (FG) led to massive cell infiltration of the subchondral bone. CONCLUSIONS: The implantation of autologous, scaffold-free, engineered cartilage constructs might best be performed beneath a PF without the use of tissue adhesives. Successfully implanted constructs showed hyaline-like characteristics in adult goats within 2 months. Long-term animal studies and pilot clinical trials are now needed to evaluate the efficacy of this treatment strategy.

High-dose therapy and autologous stem cell transplantation for children with HIV-associated non-Hodgkin lymphoma

In contrast to adults, autologous stem cell transplantation (ASCT) as part of the salvage strategy after high-dose chemo/radiotherapy in human immunodeficiency virus (HIV) related Non-Hodgkin lymphoma (NHL) is not yet established for children. We report on a 13-year patient with congenital HIV infection and refractory Burkitt lymphoma, who was successfully treated by high-dose therapy (HDT) including rituximab followed by ASCT. After 26 months follow-up the patient remains in complete remission and his HIV parameters have normalized with continued highly active antiretroviral therapy (HAART). HIV infection may no longer exclude children from ASCT as part of salvage therapy. Pediatr Blood Cancer (c) 2006 Wiley-Liss, Inc.

Placental mesenchymal stem cells as potential autologous graft for pre- and perinatal neuroregeneration

OBJECTIVE: Mesenchymal stem cells (MSCs) have a broad differentiation potential. We aimed to determine if MSCs are present in fetal membranes and placental tissue and to assess their potential to differentiate into neurogenic and mesodermal lineages. STUDY DESIGN: MSCs isolated from first and third trimester chorion and amnion and first trimester chorionic villi and characterized morphologically and by flourescence-activated cell sorting analysis. Their ability to mature under different culture conditions into various cells of mesodermal and neuroectodermal cell lines was assessed by immuno- and cytochemical staining. RESULTS: Independent of gestational age, cells isolated from fetal membranes and placenta showed typical MSC phenotype (positive for CD166, CD105, CD90, CD73, CD49e, CD44, CD29, CD13, MHC I; negative for CD14, CD34, CD45, MHC II) and were able to differentiate into mesodermal cells expressing cell markers/cytologic staining consistent with mature chondroblasts, osteoblasts, adipocytes, or myocytes and into neuronal cells presenting markers of various stages of maturation. The differentiation pattern was mainly dependent on cell type. CONCLUSION: Mesenchymal cells from chorion, amnion, and villous stroma can be differentiated into neurogenic, chondrogenic, osteogenic, adipogenic, and myogenic lineage. Placental tissue obtained during prenatal chorionic villous sampling or at delivery might be an ideal source for autologous stem cell graft for peripartum neuroregeneration and other clinical issues.

In utero transplantation of autologous and allogeneic fetal liver stem cells in ovine fetuses

OBJECTIVE: The purpose of this study was to assess the feasibility of autologous stem cell transplantation in fetal sheep and to compare short-term engraftment of allogeneic and autologous fetal liver stem cells in an immunocompetent large animal model. STUDY DESIGN: Fetal liver stem cells were collected from preimmune sheep fetuses with an open or ultrasound-guided technique. After being labeled with PKH26, the cells were transplanted intraperitoneally into allogeneic and autologous fetal recipients at 48 to 64 days of gestation. Engraftment was determined by flow cytometry and real-time polymerase chain reaction 1 to 2 weeks after transplantation. RESULTS: Fetal loss rate was 29% (allogeneic transplantation) and 73% (autologous transplantation). Engraftment of donor cells was found in all fetuses, with a level of < or =4.7% in fetal liver, spleen, bone marrow, blood and thymus. Overall, there was no difference between allogeneic and autologous grafts. CONCLUSION: Autologous in utero transplantation of fetal liver stem cells in fetal sheep is feasible, but yields a high loss rate. Differences in the major histocompatibility complex between donor and recipient seems not to have a major impact on stem cell engraftment early in gestation; major histocompatibility complex-independent donor/host competition might be responsible for low engraftment in immunocompetent recipients.

Evaluation of reparative cartilage after autologous chondrocyte implantation for osteochondritis dissecans: histology, biochemistry, and MR imaging

BACKGROUND: The aim of this study was to investigate the biochemical properties, histological and immunohistochemical appearance, and magnetic resonance (MR) imaging findings of reparative cartilage after autologous chondrocyte implantation (ACI) for osteochondritis dissecans (OCD). METHODS: Six patients (mean age 20.2 +/- 8.8 years; 13-35 years) who underwent ACI for full-thickness cartilage defects of the femoral condyle were studied. One year after the procedure, a second-look arthroscopic operation was performed with biopsy of reparative tissue. The International Cartilage Repair Society (ICRS) visual histological assessment scale was used for histological assessment. Biopsied tissue was immunohistochemically analyzed with the use of monoclonal antihuman collagen type I and monoclonal antihuman collagen type II primary antibodies. Glycosaminoglycan (GAG) concentrations in biopsied reparative cartilage samples were measured by high performance liquid chromatography (HPLC). MR imaging was performed with T1- and T2-weighted imaging and three-dimensional spoiled gradient-recalled (3D-SPGR) MR imaging. RESULTS: Four tissue samples were graded as having a mixed morphology of hyaline and fibrocartilage while the other two were graded as fibrocartilage. Average ICRS scores for each criterion were (I) 1.0 +/- 1.5; (II) 1.7 +/- 0.5; (III) 0.6 +/- 1.0; (IV) 3.0 +/- 0.0; (V) 1.8 +/- 1.5; and (VI) 2.5 +/- 1.2. Average total score was 10.7 +/- 2.8. On immunohistochemical analysis, the matrix from deep and middle layers of reparative cartilage stained positive for type II collagen; however, the surface layer did not stain well. The average GAG concentration in reparative cartilage was 76.6 +/- 4.2 microg/mg whereas that in normal cartilage was 108 +/- 11.2 microg/mg. Common complications observed on 3D-SPGR MR imaging were hypertrophy of grafted periosteum, edema-like signal in bone marrow, and incomplete repair of subchondral bone at the surgical site. Clinically, patients had significant improvements in Lysholm scores. CONCLUSIONS: In spite of a good clinical course, reparative cartilage after ACI had less GAG concentration and was inferior to healthy hyaline cartilage in histological and immunohistochemical appearance and on MRI findings.

High-dose chemotherapy followed by autologous stem cell transplantation for relapsed or refractory Hodgkin lymphoma: prognostic features and outcomes

Between January 1990 and April 2001, 115 patients received high-dose chemotherapy (HDT) followed by autologous stem cell transplantation (ASCT) for relapsed or refractory Hodgkin lymphoma (HL). With a median follow-up of 58 months (range, 1 - 175 months), 5-year progression-free survival (PFS) and overall survival (OS) were 46% and 58%, respectively. Twelve patients with primary refractory disease had a 5-year PFS of 41% and OS of 58%, not significantly different from those of the remaining cohort. Early and overall regimen related mortality were 7% and 16%, respectively. Male gender (P = 0.04) and a time to relapse (TTR) < 12 months (P = 0.03) were associated with decreased OS by univariate analysis. In multivariate analysis, TTR < 12 months remained statistically significant (P = 0.04). We have confirmed that HDT and ASCT result in long-term survival for a proportion of patients with relapsed or refractory HL. All patients, including those with primary refractory disease, benefited from HDT and ASCT.

Percutaneous autologous venous valve transplantation: short-term feasibility study in an ovine model

BACKGROUND: Limited experience with bioprosthetic venous valve percutaneously inserted into femoral veins in 15 patients has been promising in short-term results only to show disappointing long-term results. Percutaneous autogenous venous valve (PAVV) transplantation was explored in an ovine model as a possible alternative treatment. METHODS: PAVV consisted of a vein segment containing a valve that was attached to a stent template. The stent templates (n = 9) were designed and hand made in our research laboratory. They consist of two stainless steel square stents 13 or 15 mm in diameter to fit the ovine jugular veins (JV), which ranges from 10 to 15 mm in diameter. A valve-containing segment of JV was harvested and attached with sutures and barbs inside the stent template (n = 9). The valve devices were then manually folded and front loaded inside the 4 cm chamber of the 13F delivery sheath and delivered into the contralateral JV by femoral vein approach. Transplanted PAVVs were studied by immediate and 3 months venograms. Animals were euthanized at 3 months, and jugular veins harvested to perform angioscopic evaluations in vitro. RESULTS: PAVV transplantation was successful in all nine animals. Good valve function with no reflux was observed on immediate and 3 months venograms in eight valves. The transplanted maximal JV diameter ranged from 10.2 mm to 15.4 mm (mean 13.1 +/- 1.5 mm). Venoscopic examination revealed intact, flexible, nonthickened valve leaflets in eight specimens. One PAVV exhibited normal function of one leaflet only; the other cusp was accidentally cut during the transplantation procedure. All transplanted autologous valves were free of thrombus and incorporated into the vein wall of the host vessel. CONCLUSION: This study demonstrated that autogenous valve transplants remained patent and competent without long-term anticoagulation for up to 3 months. The percutaneous autogenous venous valve may provide in future minimally invasive treatment for patients with chronic deep venous insufficiency, but long-term studies need to be done to document its continued patency and function.

Steady-state diffusion imaging for MR in-vivo evaluation of reparative cartilage after matrix-associated autologous chondrocyte transplantation at 3 tesla--preliminary results

OBJECTIVES: To demonstrate the feasibility of time-reversed fast imaging with steady-state precession (FISP) called PSIF for diffusion-weighted imaging of cartilage and cartilage transplants in a clinical study. MATERIAL AND METHODS: In a cross-sectional study 15 patients underwent MRI using a 3D partially balanced steady-state gradient echo pulse sequence with and without diffusion weighting at two different time points after matrix-associated autologous cartilage transplantation (MACT). Mean diffusion quotients (signal intensity without diffusion-weighting divided by signal intensity with diffusion weighting) within the cartilage transplants were compared to diffusion quotients found in normal cartilage. RESULTS: The global diffusion quotient found in repair cartilage was significantly higher than diffusion values in normal cartilage (p<0.05). There was a decrease between the earlier and the later time point after surgery. CONCLUSIONS: In-vivo diffusion-weighted imaging based on the PSIF technique is possible. Our preliminary results show follow-up of cartilage transplant maturation in patients may provide additional information to morphological assessment.

Longitudinal evaluation of cartilage composition of matrix-associated autologous chondrocyte transplants with 3-T delayed gadolinium-enhanced MRI of cartilage

OBJECTIVE: The purposes of this study were to use delayed gadolinium-enhanced MRI of cartilage (dGEMRIC) to evaluate the zonal distribution of glycosaminoglycans (GAGs) in normal cartilage and repair tissue and to use 3-T MRI to monitor the GAG content in matrix-associated autologous chondrocyte transplants. SUBJECTS AND METHODS: Fifteen patients who underwent matrix-associated autologous chondrocyte transplantation in the knee joint underwent MRI at baseline and 3-T follow-up MRI 1 year later. Total and zonal changes in longitudinal relaxivity (deltaR1) and relative deltaR1 were calculated for repair tissue and normal hyaline cartilage and compared by use of analysis of variance. RESULTS: There was a significant difference between the mean deltaR1 of repair tissue and that of reference cartilage at baseline and follow-up (p < 0.001). There was a significant increase in deltaR1 value and a decrease in GAG content from the deep layer to the superficial layer in the reference cartilage and almost no variation and significantly higher values for the repair tissue at both examinations. At 1-year follow-up imaging, there was a 22.7% decrease in deltaR1 value in the deep zone of the transplant. CONCLUSION: T1 mapping with dGEMRIC at 3 T shows the zonal structure of normal hyaline cartilage, highly reduced zonal variations in repair tissue, and a tendency toward an increase in global and zonal GAG content 1 year after transplantation.

Multimodal approach in the use of clinical scoring, morphological MRI and biochemical T2-mapping and diffusion-weighted imaging in their ability to assess differences between cartilage repair tissue after microfracture therapy and matrix-associated autologous chondrocyte transplantation: a pilot study

OBJECTIVE: The aim of the present pilot study is to show initial results of a multimodal approach using clinical scoring, morphological magnetic resonance imaging (MRI) and biochemical T2-relaxation and diffusion-weighted imaging (DWI) in their ability to assess differences between cartilage repair tissue after microfracture therapy (MFX) and matrix-associated autologous chondrocyte transplantation (MACT). METHOD: Twenty patients were cross-sectionally evaluated at different post-operative intervals from 12 to 63 months after MFX and 12-59 months after MACT. The two groups were matched by age (MFX: 36.0+/-10.4 years; MACT: 35.1+/-7.7 years) and post-operative interval (MFX: 32.6+/-16.7 months; MACT: 31.7+/-18.3 months). After clinical evaluation using the Lysholm score, 3T-MRI was performed obtaining the MR observation of cartilage repair tissue (MOCART) score as well as T2-mapping and DWI for multi-parametric MRI. Quantitative T2-relaxation was achieved using a multi-echo spin-echo sequence; semi-quantitative diffusion-quotient (signal intensity without diffusion-weighting divided by signal intensity with diffusion weighting) was prepared by a partially balanced, steady-state gradient-echo pulse sequence. RESULTS: No differences in Lysholm (P=0.420) or MOCART (P=0.209) score were observed between MFX and MACT. T2-mapping showed lower T2 values after MFX compared to MACT (P=0.039). DWI distinguished between healthy cartilage and cartilage repair tissue in both procedures (MFX: P=0.001; MACT: P=0.007). Correlations were found between the Lysholm and the MOCART score (Pearson: 0.484; P=0.031), between the Lysholm score and DWI (Pearson:-0.557; P=0.011) and a trend between the Lysholm score and T2 (Person: 0.304; P=0.193). CONCLUSION: Using T2-mapping and DWI, additional information could be gained compared to clinical scoring or morphological MRI. In combination clinical, MR-morphological and MR-biochemical parameters can be seen as a promising multimodal tool in the follow-up of cartilage repair.

Quantitative T2 mapping during follow-up after matrix-associated autologous chondrocyte transplantation (MACT): full-thickness and zonal evaluation to visualize the maturation of cartilage repair tissue

The purpose of this article was to evaluate the potential of in vivo zonal T2-mapping as a noninvasive tool in the longitudinal visualization of cartilage repair tissue maturation after matrix-associated autologous chondrocyte transplantation (MACT). Fifteen patients were treated with MACT and evaluated cross-sectionally, with a baseline MRI at a follow-up of 19.7 +/- 12.1 months after cartilage transplantation surgery of the knee. In the same 15 patients, 12 months later (31.7 +/- 12.0 months after surgery), a longitudinal 1-year follow-up MRI was obtained. MRI was performed on a 3 Tesla MR scanner; morphological evaluation was performed using a double-echo steady-state sequence; T2 maps were calculated from a multiecho, spin-echo sequence. Quantitative mean (full-thickness) and zonal (deep and superficial) T2 values were calculated in the cartilage repair area and in control cartilage sites. A statistical analysis of variance was performed. Full-tickness T2 values showed no significant difference between sites of healthy cartilage and cartilage repair tissue (p < 0.05). Using zonal T2 evaluation, healthy cartilage showed a significant increase from the deep to superficial cartilage layers (p < 0.05). Cartilage repair tissue after MACT showed no significant zonal increase from deep to superficial cartilage areas during baseline MRI (p > 0.05); however, during the 1-year follow-up, a significant zonal stratification could be observed (p < 0.05). Morphological evaluation showed no significant difference between the baseline and the 1-year follow-up MRI. T2 mapping seems to be more sensitive in revealing changes in the repair tissue compared to morphological MRI. In vivo zonal T2 assessment may be sensitive enough to characterize the maturation of cartilage repair tissue.