Autologous microfragmented adipose tissue treatment of knee osteoarthritis demonstrates effectiveness in 68% of patients at 4-year follow-up

BACKGROUND

Adipose tissue-derived stem cells are an interesting therapeutic option for early knee osteoarthritis (OA) treatment due to their high plasticity, easiness of harvesting and rapidity of administration. The aim of this study was to evaluate the medium-term effectiveness and safety of Microfragmented Autologous Fat Tissue (MFAT) injection treatment at 4-year follow-up and to investigate potential correlations among patients' pre-treatment clinical condition and clinical outcomes to identify possible predicting factors for procedure success or failure.

PATIENTS AND METHODS

This is a prospective trial enrolling 46 patients with diagnosis of symptomatic knee OA and failure of previous conservative measures who underwent diagnostic arthroscopy and single autologous MFAT injection between June 2017 and July 2018. Patients were assessed with repeated clinical scoring systems at baseline, 6 months, 1 and 4 years after surgery. The evaluation included demographic characteristics, arthroscopic findings, and stem cell number from injected tissue.

RESULTS

No major complications were reported during follow-up period and there was a significant increase of Lysholm knee score from baseline value of 61.7 ± 13.8 to 79.5 ± 16.9 at 4 years (p < 0.001). The WOMAC score increased from a baseline value of 66.5 ± 14.7 to 82.8 ± 15.7 at 4 years (p < 0.001) and there was a significant decrease of VAS pain score from baseline value of 6.3 ± 1.5 to 3.5 ± 2.6 at 4-year follow-up (p < 0.001). ROM improved significantly from 118.4 ± 2.6 to 122.5 ± 2.5 at 12 months (p < 0.001), but did not improve at 4 years (p > 0.05). 15 patients (32.6%) were considered treatment failures, because they required secondary surgery, further injection therapy or experienced symptoms persistence. Patient with synovitis had 75% failure rate, although synovitis did not result as a statistically significant factor influencing clinical outcome up to 4-year follow-up (p = 0.058). Age, cartilage defects severity, BMI, concomitant procedures, and stem cell number from injected MFAT did not show any significant correlation with the results.

CONCLUSIONS

MFAT intra-articular injection is a safe procedure with positive improvements up to 4-year follow-up in patients with early knee OA. These findings suggest MFAT could be a minimally invasive treatment of early knee OA with durable benefits at mid-term evaluation.

TRIAL REGISTRATION

IRB number ID-3522.

Enhanced Antimicrobial and Antibiofilm Effect of New Colistin-Loaded Human Albumin Nanoparticles

Multidrug-resistant (MDR) Gram-negative bacteria (GNB), such as Acinetobacter and Klebsiella, are responsible for severe hospital-acquired infections. Colistin, despite its toxicity and low tissue penetration, is considered the last resort antibiotic against these microorganisms. Of concern, the use of Colistin has recently been compromised by the emergence of Colistin resistance. Herein, we developed a new formulation consisting of multifunctional chitosan-coated human albumin nanoparticles for the delivery of Colistin (Col/haNPs). Col/haNPs were in vitro characterized for encapsulation efficiency, drug release, stability and cytotoxicity and were evaluated for antibacterial activity against MDR GNB (Acinetobacter baumannii and Klebsiella pneumoniae). Col/haNPs showed sizes lower than 200 nm, high encapsulation efficiency (98.65%) and prolonged in vitro release of Colistin. The safety of the nanoformulation was demonstrated by a negligible cytotoxicity on human fibroblasts and hemolytic activity. Col/haNPs evidenced a high antibacterial effect with a significant decrease in MIC values compared to free Colistin, in particular against Col-resistant strains with a pronounced decline of bacterial growth over time. Moreover, Col/haNPs exhibited an inhibitory effect on biofilm formation that was 4 and 60 fold higher compared to free Colistin, respectively for Colistin susceptible and resistant A. baumannii. Our findings suggest that Col/haNPs could represent a promising Colistin nanocarrier with high antimicrobial activity on MDR GNB.

CSF1R Is Required for Differentiation and Migration of Langerhans Cells and Langerhans Cell Histiocytosis

Langerhans cell histiocytosis (LCH) is a rare disorder characterized by tissue accumulation of CD1a⁺CD207⁺ LCH cells. In LCH, somatic mutations of the BRAF ^V600E gene have been detected in tissue LCH cells, bone marrow CD34⁺ hematopoietic stem cells, circulating CD14⁺ monocytes, and BDCA1⁺ myeloid dendritic cells (DC). Targeting BRAF ^V600E in clonal Langerhans cells (LC) and their precursors is a potential treatment option for patients whose tumors have the mutation. The development of mouse macrophages and LCs is regulated by the CSF1 receptor (CSF1R). In patients with diffuse-type tenosynovial giant cell tumors, CSF1R inhibition depletes tumor-associated macrophages (TAM) with therapeutic efficacy; however, CSF1R signaling in LCs and LCH has not been investigated. We found through IHC and flow cytometry that CSF1R is normally expressed on human CD1a⁺CD207⁺ LCs in the epidermis and stratified epithelia. LCs that were differentiated from CD14⁺ monocytes, BDCA1⁺ DCs, and CD34⁺ cord blood progenitors expressed CSF1R that was downregulated upon maturation. Immature LCs migrated toward CSF1, but not IL34. Administration of the c-FMS/CSF1R kinase inhibitors GW2580 and BLZ945 significantly reduced human LC migration. In LCH clinical samples, LCH cells (including BRAF ^V600E cells) and TAMs retained high expression of CSF1R. We also detected the presence of transcripts for its ligand, CSF1, but not IL34, in all tested LCH cases. CSF1R and CSF1 expression in LCH, and their role in LC migration and differentiation, suggests CSF1R signaling blockade as a candidate rational approach for treatment of LCH, including the BRAF ^V600E and wild-type forms of the disease.

Independent Functioning in Nonagenarians Living in a Rural Italian Community: The Mugello Study

Nonagenarians are a fast-growing population deserving specific research. We explored the prevalence and characteristics of functionally independent nonagenarians from a rural community-dwelling Italian population. Data were collected in the Mugello Study; 475 persons aged ≥90 years (median age, 92) underwent a home-based clinical and functional assessment, including psychosocial, clinical, functional, and lifestyle history and status and physical and instrumental examinations. Sixty-eight (15%) persons reported no need for help in basic and instrumental daily living activities. Among variables significantly associated with independent functionality after age- and gender-adjusted cross-sectional analysis, lower body mass index (BMI; p = .034) and depressive symptoms (p = .028), higher current physical activity (p < .001), better cognitive status (p = .033), and lower medication intake (p = .048) were associated with reporting no disability in the logistic regression analysis. Disability was mainly associated with current lifestyle-related potentially modifiable factors. Thus, lifestyle-oriented multidimensional interventions, should be developed and evaluated for their potential effects on functionality, even in the oldest old.

In Vitro Enhanced Skin Permeation and Retention of Imiquimod Loaded in β-Cyclodextrin Nanosponge Hydrogel

Imiquimod (IMQ) is an immune response modifier clinically used for the treatment of various topical diseases. However, its poor aqueous solubility and skin penetration capability make the topical delivery of IMQ a challenging task. This work aims at developing a nanomedicine-based topical formulation, carrying IMQ to control the scarring process for the treatment of aberrant wounds. For this purpose, IMQ was loaded in β-cyclodextrin-based nanosponges and dispersed in a hydrogel suitable for dermal application. The formulation was characterized in vitro and compared with IMQ inclusion complexes, with (2-hydroxy)propyl β-cyclodextrin(HPβCD) and carboxymethyl β-cyclodextrin (CMβCD) showing enhanced penetration properties. The hydrogel containing IMQ-loaded nanosponges could act as a drug reservoir and guarantee the sustained release of IMQ through the skin. A greater inhibitory effect on fibroblast proliferation was observed for IMQ loaded in nanosponges compared to the other formulations.

Concentrated adipose tissue infusion for the treatment of knee osteoarthritis: clinical and histological observations

PURPOSE

Osteoarthritis (OA) is characterized by articular cartilage degeneration and subchondral bone sclerosis. OA can benefit of non-surgical treatments with collagenase-isolated stromal vascular fraction (SVF) or cultured-expanded mesenchymal stem cells (ASCs). To avoid high manipulation of the lipoaspirate needed to obtain ASCs and SVF, we investigated whether articular infusions of autologous concentrated adipose tissue are an effective treatment for knee OA patients.

METHODS

The knee of 20 OA patients was intra-articularly injected with autologous concentrated adipose tissue, obtained after centrifugation of lipoaspirate. Patients' articular functionality and pain were evaluated by VAS and WOMAC scores at three, six and 18 months from infusion. The osteogenic and chondrogenic ability of ASCs contained in the injected adipose tissue was studied in in vitro primary osteoblast and chondrocyte cell cultures, also plated on 3D-bone scaffold. Knee articular biopsies of patients previously treated with adipose tissue were analyzed. Immunohistochemistry (IHC) and scanning electron microscopy (SEM) were performed to detect cell differentiation and tissue regeneration.

RESULTS

The treatment resulted safe, and all patients reported an improvement in terms of pain reduction and increase of function. According to the osteogenic or chondrogenic stimulation, ASCs expressed alkaline phosphatase or aggrecan, respectively. The presence of a layer of newly formed tissue was visualized by IHC staining and SEM. The biopsy of previously treated knee joints showed new tissue formation, starting from the bone side of the osteochondral lesion.

CONCLUSIONS

Overall our data indicate that adipose tissue infusion stimulates tissue regeneration and might be considered a safe treatment for knee OA.

Vitamin D Receptor Is Necessary for Mitochondrial Function and Cell Health

Vitamin D receptor (VDR) mediates many genomic and non-genomic effects of vitamin D. Recently, the mitochondrial effects of vitamin D have been characterized in many cell types. In this article, we investigated the importance of VDR not only in mitochondrial activity and integrity but also in cell health. The silencing of the receptor in different healthy, non-transformed, and cancer cells initially decreased cell growth and modulated the cell cycle. We demonstrated that, in silenced cells, the increased respiratory activity was associated with elevated reactive oxygen species (ROS) production. In the long run, the absence of the receptor caused impairment of mitochondrial integrity and, finally, cell death. Our data reveal that VDR plays a central role in protecting cells from excessive respiration and production of ROS that leads to cell damage. Because we confirmed our observations in different models of both normal and cancer cells, we conclude that VDR is essential for the health of human tissues.

Adaptive Regulation of Osteopontin Production by Dendritic Cells Through the Bidirectional Interaction With Mesenchymal Stromal Cells

Mesenchymal stromal cells (MSCs) exert immunosuppressive effects on immune cells including dendritic cells (DCs). However, many details of the bidirectional interaction of MSCs with DCs are still unsolved and information on key molecules by which DCs can modulate MSC functions is limited. Here, we report that osteopontin (OPN), a cytokine involved in homeostatic and pathophysiologic responses, is constitutively expressed by DCs and regulated in the DC/MSC cocultures depending on the activation state of MSCs. Resting MSCs promoted OPN production, whereas the production of OPN was suppressed when MSCs were activated by proinflammatory cytokines (i.e., TNF-α, IL-6, and IL-1β). OPN induction required cell-to-cell contact, mediated at least in part, by β1 integrin (CD29). Conversely, activated MSCs inhibited the release of OPN via the production of soluble factors with a major role played by Prostaglandin E₂ (PGE₂). Accordingly, pretreatment with indomethacin significantly abrogated the MSC-mediated suppression of OPN while the direct addition of exogenous PGE₂ inhibited OPN production by DCs. Furthermore, DC-conditioned medium promoted osteogenic differentiation of MSCs with a concomitant inhibition of adipogenesis. These effects were paralleled by the repression of the adipogenic markers PPARγ, adiponectin, and FABP4, and induction of the osteogenic markers alkaline phosphatase, RUNX2, and of the bone-anabolic chemokine CCL5. Notably, blocking OPN activity with RGD peptides or with an antibody against CD29, one of the OPN receptors, prevented the effects of DC-conditioned medium on MSC differentiation and CCL5 induction. Because MSCs have a key role in maintenance of bone marrow (BM) hematopoietic stem cell niche through reciprocal regulation with immune cells, we investigated the possible MSC/DC interaction in human BM by immunohistochemistry. Although DCs (CD1c⁺) are a small percentage of BM cells, we demonstrated colocalization of CD271⁺ MSCs with CD1c⁺ DCs in normal and myelodysplastic BM. OPN reactivity was observed in occasional CD1c⁺ cells in the proximity of CD271⁺ MSCs. Altogether, these results candidate OPN as a signal modulated by MSCs according to their activation status and involved in DC regulation of MSC differentiation.

A thermal gradient modulates the oxidative metabolism and growth of human keratinocytes

During their spatial and differentiative progression, keratinocytes face a thermal gradient, from 37 °C in the proliferating basal layer to 32 °C found in skin surface. In our study, we hypothesized that this difference in temperature must be balanced by increasing the heat produced during respiratory activity. We demonstrated that at 33 °C human primary keratinocytes and HaCaT cells raised mitochondrial energy metabolism, but not glycolytic activity. At 33 °C, the increased mitochondrial ATP synthesis was associated with a strong induction of the modulator of the respiratory chain estrogen receptor β, whereas uncoupling protein 1 expression was not changed. The enhanced mitochondrial oxidative metabolism was accompanied by a remarkable reduction in proliferation. These results suggest that environmental temperature can modulate the energy metabolism and proliferation of human keratinocytes.

Skin contamination as pathway for nicotine intoxication in vapers

Growing warnings on health effects related to electronic cigarettes have met inconclusive findings at present. This study analyzed the in vitro percutaneous absorption of nicotine resulting by skin contamination with two e-liquids (refill 1 and 2) containing nicotine at 1.8%. Donor chambers of 6 Franz cells for each refill liquid were filled with 1mL of nicotine e-liquid for 24h; at selected intervals, 1.5mL of the receptor solutions were collected for nicotine concentration analysis by mean gas chromatography-mass spectrometry (LOD: 0.01μg/mL). The experiment was repeated removing the nicotine donor solution after 10min from the application and rinsing the skin surface three times with 3.0mL of milliQ water. A total of 12 cells with 24h exposure and 12 cells washed were studied. The mean concentration of nicotine in the receiving phase at the end of the experiment was 54.9±29.5 and 30.2±18.4μg/cm² for refill 1 and 2 respectively and significantly lower in washed cells (4.7±2.4 and 3.5±1.3μg/cm²). The skin absorption of nicotine can lead to minor health illness in vapers, while caution must be paid to dermal contamination by e liquids in children. The skin cleaning significantly reduced the transdermal absorption kinetic and intradermal deposition of nicotine.

Adipose Derived-Mesenchymal Stem Cells Viability and Differentiating Features for Orthopaedic Reparative Applications: Banking of Adipose Tissue

Osteoarthritis is characterized by loss of articular cartilage also due to reduced chondrogenic activity of mesenchymal stem cells (MSCs) from patients. Adipose tissue is an attractive source of MSCs (ATD-MSCs), representing an effective tool for reparative medicine, particularly for treatment of osteoarthritis, due to their chondrogenic and osteogenic differentiation capability. The treatment of symptomatic knee arthritis with ATD-MSCs proved effective with a single infusion, but multiple infusions could be also more efficacious. Here we studied some crucial aspects of adipose tissue banking procedures, evaluating ATD-MSCs viability, and differentiation capability after cryopreservation, to guarantee the quality of the tissue for multiple infusions. We reported that the presence of local anesthetic during lipoaspiration negatively affects cell viability of cryopreserved adipose tissue and cell growth of ATD-MSCs in culture. We observed that DMSO guarantees a faster growth of ATD-MSCs in culture than trehalose. At last, ATD-MSCs derived from fresh and cryopreserved samples at -80°C and -196°C showed viability and differentiation ability comparable to fresh samples. These data indicate that cryopreservation of adipose tissue at -80°C and -196°C is equivalent and preserves the content of ATD-MSCs in Stromal Vascular Fraction (SVF), guaranteeing the differentiation ability of ATD-MSCs.

Ex Vivo Dermis Mechanical Behavior in Relation to Decellularization Treatment Length

Background:

The dermis is a commonly used source tissue for biologic scaffolds; all cellular and nuclear materials need to be removed to limit the inflammatory immune response by the host organism. The decellularization is critical because it must preserve the structural integrity of the extracellular matrix. This work has analyzed a decellularization procedure commonly followed for the dermal tissue that is a chemical treatment with sodium hydroxide. The goal of this work is to identify the optimal treatment length on the basis of structural properties.

Methods:

Tensile tests have been performed on the native tissue and on tissues decellularized for 1-7 weeks in sodium hydroxide. The collected data have been analyzed through Tukey-Kramer test to assess if the mechanical properties (ultimate tensile stress and elastic modulus) of decellularized tissues were significantly different from the properties of the native tissue. These tests have been performed on specimens cut along two orthogonal directions (parallel and perpendicular to Langer’s lines).

Results:

The decellularization treatment performed with sodium hydroxide in general weakens the tissue: both the ultimate stress and the elastic modulus get lower. The structural properties along Langer lines orientation are more strongly impacted, while the structural properties orthogonal to Langer lines can be preserved with an optimal duration of the decellularization treatment that is 5-6 weeks.

Conclusion:

The duration of the decellularization treatment is critical not only to reach a complete decellularization, but also to preserve the mechanical properties of the tissue; 5-6 week treatment performed with sodium hydroxide allows preserving the mechanical properties of the native tissue perpendicularly to Langer lines orientation, and minimizing the impact of the decellularization process on the mechanical properties along the Langer lines orientation.

Regulation of Langerhans cell functions in a hypoxic environment

Langerhans cells (LCs) are a specialized dendritic cell subset that resides in the epidermis and mucosal epithelia and is critical for the orchestration of skin immunity. Recent evidence suggest that LCs are involved in aberrant wound healing and in the development of hypertrophic scars and chronic wounds, which are characterized by a hypoxic environment. Understanding LCs biology under hypoxia may, thus, lead to the identification of novel pathogenetic mechanisms of wound repair disorders and open new therapeutic opportunities to improve wound healing. In this study, we characterize a previously unrecognized role for hypoxia in significantly affecting the phenotype and functional properties of human monocyte-derived LCs, impairing their ability to stimulate naive T cell responses, and identify the triggering receptor expressed on myeloid (TREM)-1, a member of the Ig immunoregulatory receptor family, as a new hypoxia-inducible gene in LCs and an activator of their proinflammatory and Th1-polarizing functions in a hypoxic environment. Furthermore, we provide the first evidence of TREM-1 expression in vivo in LCs infiltrating hypoxic areas of active hypertrophic scars and decubitous ulcers, pointing to a potential pathogenic role of this molecule in wound repair disorders.

KEY MESSAGES

Hypoxia modulates surface molecule expression and cytokine profile in Langerhans cells. Hypoxia impairs human Langerhans cell stimulatory activity on naive T cells. Hypoxia selectively induces TREM-1 expression in human Langerhans cells. TREM-1 engagement stimulates Langerhans cell inflammatory and Th1-polarizing activity. TREM-1 is expressed in vivo in Langerhans cells infiltrating hypoxic skin lesions.

Glycerolized Reticular Dermis as a New Human Acellular Dermal Matrix: An Exploratory Study

Human Acellular Dermal Matrices (HADM) are employed in various reconstructive surgery procedures as scaffolds for autologous tissue regeneration. The aim of this project was to develop a new type of HADM for clinical use, composed of glycerolized reticular dermis decellularized through incubation and tilting in Dulbecco's Modified Eagle's Medium (DMEM). This manufacturing method was compared with a decellularization procedure already described in the literature, based on the use of sodium hydroxide (NaOH), on samples from 28 donors. Cell viability was assessed using an MTT assay and microbiological monitoring was performed on all samples processed after each step. Two surgeons evaluated the biomechanical characteristics of grafts of increasing thickness. The effects of the different decellularization protocols were assessed by means of histological examination and immunohistochemistry, and residual DNA after decellularization was quantified using a real-time TaqMan MGB probe. Finally, we compared the results of DMEM based decellularization protocol on reticular dermis derived samples with the results of the same protocol applied on papillary dermis derived grafts. Our experimental results indicated that the use of glycerolized reticular dermis after 5 weeks of treatment with DMEM results in an HADM with good handling and biocompatibility properties.

Mitochondrial and lipogenic effects of vitamin D on differentiating and proliferating human keratinocytes

Even in cells that are resistant to the differentiating effects of vitamin D, the activated vitamin D receptor (VDR) can downregulate the mitochondrial respiratory chain and sustain cell growth through enhancing the activity of biosynthetic pathways. The aim of this study was to investigate whether vitamin D is effective also in modulating mitochondria and biosynthetic metabolism of differentiating cells. We compared the effect of vitamin D on two cellular models: the primary human keratinocytes, differentiating and sensitive to the genomic action of VDR, and the human keratinocyte cell line HaCaT, characterized by a rapid growth and resistance to vitamin D. We analysed the nuclear translocation and features of VDR, the effects of vitamin D on mitochondrial transcription and the consequences on lipid biosynthetic fate. We found that the negative modulation of respiratory chain is a general mechanism of action of vitamin D, but at high doses, the HaCaT cells became resistant to mitochondrial effects by upregulating the catabolic enzyme CYP24 hydroxylase. In differentiating keratinocytes, vitamin D treatment promoted intracellular lipid deposition, likewise the inhibitor of respiratory chain stigmatellin, whereas in proliferating HaCaT, this biosynthetic pathway was not inducible by the hormone. By linking the results on respiratory chain and lipid accumulation, we conclude that vitamin D, by suppressing respiratory chain transcription in all keratinocytes, is able to support both the proliferation and the specialized metabolism of differentiating cells. Through mitochondrial control, vitamin D can have an essential role in all the metabolic phenotypes occurring in healthy and diseased skin.

Constructal thermodynamics combined with infrared experiments to evaluate temperature differences in cells

The aim of this work was to evaluate differences in energy flows between normal and immortalized cells when these distinct biological systems are exposed to environmental stimulation. These differences were considered using a constructal thermodynamic approach, and were subsequently verified experimentally. The application of constructal law to cell analysis led to the conclusion that temperature differences between cells with distinct behaviour can be amplified by interaction between cells and external fields. Experimental validation of the principle was carried out on two cellular models exposed to electromagnetic fields. By infrared thermography we were able to assess small changes in heat dissipation measured as a variation in cell internal energy. The experimental data thus obtained are in agreement with the theoretical calculation, because they show a different thermal dispersion pattern when normal and immortalized cells are exposed to electromagnetic fields. By using two methods that support and validate each other, we have demonstrated that the cell/environment interaction can be exploited to enhance cell behavior differences, in particular heat dissipation. We propose infrared thermography as a technique effective in discriminating distinct patterns of thermal dispersion and therefore able to distinguish a normal phenotype from a transformed one.

An acidic microenvironment sets the humoral pattern recognition molecule PTX3 in a tissue repair mode

Doni et al. use four tissue damage models in mice and find that the fluid phase pattern recognition molecule pentraxin 3 (PTX3) plays a role in tissue remodeling and repair. PTX3 binds fibrinogen/fibrin and plasminogen at an acidic pH within tissues. Mice deficient in PTX3 present defects in fibrin deposition, clot formation, collagen deposition, and macrophage-mediated fibrinolysis.

Pentraxin 3 (PTX3) is a fluid-phase pattern recognition molecule and a key component of the humoral arm of innate immunity. In four different models of tissue damage in mice, PTX3 deficiency was associated with increased fibrin deposition and persistence, and thicker clots, followed by increased collagen deposition, when compared with controls. Ptx3-deficient macrophages showed defective pericellular fibrinolysis in vitro. PTX3-bound fibrinogen/fibrin and plasminogen at acidic pH and increased plasmin-mediated fibrinolysis. The second exon-encoded N-terminal domain of PTX3 recapitulated the activity of the intact molecule. Thus, a prototypic component of humoral innate immunity, PTX3, plays a nonredundant role in the orchestration of tissue repair and remodeling. Tissue acidification resulting from metabolic adaptation during tissue repair sets PTX3 in a tissue remodeling and repair mode, suggesting that matrix and microbial recognition are common, ancestral features of the humoral arm of innate immunity.

Predictors of response to exercise therapy for chronic low back pain: result of a prospective study with one year follow-up

BACKGROUND

Low back pain (LBP) management is a critical public health issue in all developed countries. Most approaches show evidence of effects only in the short term.

AIM

To identify predictors of functional outcome on discharge and at 1 year.

DESIGN

Prospective cohort study.

SETTING

Outpatient rehabilitation department.

POPULATION

Patients aged >18 addressed to exercise therapy for persisting LBP.

METHODS

The individually designed physiotherapy program provided 7 sessions (45'); patients were given advice to stay active and continue exercise program on discharge. Baseline (T0) assessment included: age, sex, time since onset, pain-related drug use, previous treatments, job, physical activity, pain (NRS) and Mental Health (SF36 sub-score); at follow-up (T2), we also enquired to on adherence to exercise prescription, physical activity, drugs. The primary outcome measure was the Roland and Morris Disability Questionnaire (RMDQ) patients scoring improvement >30% (minimal clinical important difference) were classified as respondent.

RESULTS

211 completed follow-up (70% women; age 70.4±11.9). Average RMDQ score was reduced by 35% at T1 and by 31% at T2; NRS by 28% (T1) and 24% (T2); 125 patients (59%) were responders on discharge; 106 (50%) at follow-up. Only higher baseline NRS predicted poor response to treatment at T1 (OR=0.83, 95% CI: 0.71-0.95, P=0.012)). At T2, older age (OR=0.94, 95% CI: 0.91-0.98, P=0.003), drug use (OR=0.18, 95% CI: 0.08-4,69, P<0.001) and previous treatments (OR 0.33, 95% CI: 0.15 to 0.71, P=0.004) were significantly associated with poor response, while, baseline mental health (OR=1.1, 95% CI: 1.01-1.24, P=0.02) and adherence to exercises for LBP (OR=2.10, 95% CI: 1.03-4.42, P=0.04) predicted improved outcome.

CONCLUSIONS

The individually designed exercise therapy program for chronic LBP was associated to clinically significant functional improvement both on discharge and at 1 year. Only severe pain intensity predicted poor treatment response on discharge. At one year, younger age and better mental health predicted improved outcome, while use of drugs and previous LBP treatments were associated with worse response. Adherence to the exercise program almost doubled the probability of a favorable outcome.

CLINICAL REHABILITATION IMPACT

Adherence to an extensive individually designed exercise therapy program improves long term functional outcome of chronic low back pain.

In vitro CMV-infection model in fresh and glycerolized skin graft

Viral infections, especially cytomegalovirus (CMV), are a cause of death in burned patients. Aim of this study was to perform an in vitro CMV-infection model comparing fresh and glycerol-treated fibroblasts and keratinocytes. Cells were plated in plates for the two conditions. Each plate was set up with CMV dilutions. Immunofluorescence and real time PCR assays were performed. The assays were negative in both fresh and glycerolized keratinocytes. For fibroblasts, CMV-DNA was positive in both conditions and immunofluorescence test only in fresh cells. Glycerol at 85% confirms its strong virucidal effect as reported also for other viruses.

C/EBPδ gene targets in human keratinocytes

C/EBPs are a family of B-Zip transcription factors -TFs- involved in the regulation of differentiation in several tissues. The two most studied members -C/EBPα and C/EBPβ- play important roles in skin homeostasis and their ablation reveals cells with stem cells signatures. Much less is known about C/EBPδ which is highly expressed in the granular layer of interfollicular epidermis and is a direct target of p63, the master regular of multilayered epithelia. We identified C/EBPδ target genes in human primary keratinocytes by ChIP on chip and profiling of cells functionally inactivated with siRNA. Categorization suggests a role in differentiation and control of cell-cycle, particularly of G2/M genes. Among positively controlled targets are numerous genes involved in barrier function. Functional inactivation of C/EBPδ as well as overexpressions of two TF targets -MafB and SOX2- affect expression of markers of keratinocyte differentiation. We performed IHC on skin tumor tissue arrays: expression of C/EBPδ is lost in Basal Cell Carcinomas, but a majority of Squamous Cell Carcinomas showed elevated levels of the protein. Our data indicate that C/EBPδ plays a role in late stages of keratinocyte differentiation.

Human cytomegalovirus load in fresh and glycerolized skin grafts

This study evaluated the detection of Human Cytomegalovirus (HCMV)-DNA in donors' skin samples. HCMV-DNA was quantified in 100 skin specimens, including 50 fresh samples and as many corresponding glycerol-preserved specimens by a home-made Real Time PCR. HCMV-DNA was detected in 19/50 (38%) fresh specimens and 23/50 (46%) glycerol-preserved (p = n.s.). Nevertheless, the mere detection of HCMV-DNA does not imply the presence of infectious virions and therefore does not imply a risk of HCMV transmission, as treatment with glycerol is particularly efficacious in inactivating viral particles. Therefore, HCMV serology confirms its pivotal role in the setting of skin grafting.

Fibroblasts from patients with Diamond-Blackfan anaemia show abnormal expression of genes involved in protein synthesis, amino acid metabolism and cancer

BACKGROUND

Diamond-Blackfan anaemia (DBA) is a rare inherited red cell hypoplasia characterised by a defect in the maturation of erythroid progenitors and in some cases associated with malformations. Patients have an increased risk of solid tumors. Mutations have been found in several ribosomal protein (RP) genes, i.e RPS19, RPS24, RPS17, RPL5, RPL11, RPL35A. Studies in haematopoietic progenitors from patients show that haplo-insufficiency of an RP impairs rRNA processing and ribosome biogenesis. DBA lymphocytes show reduced protein synthesis and fibroblasts display abnormal rRNA processing and impaired proliferation.

RESULTS

To evaluate the involvement of non-haematopoietic tissues in DBA, we have analysed global gene expression in fibroblasts from DBA patients compared to healthy controls. Microarray expression profiling using Affymetrix GeneChip Human Genome U133A 2.0 Arrays revealed that 421 genes are differentially expressed in DBA patient fibroblasts. These genes include a large cluster of ribosomal proteins and factors involved in protein synthesis and amino acid metabolism, as well as genes associated to cell death, cancer and tissue development.

CONCLUSION

This analysis reports for the first time an abnormal gene expression profile in a non-haematopoietic cell type in DBA. These data support the hypothesis that DBA may be due to a defect in general or specific protein synthesis.

An integrated humoral and cellular response is elicited in pancreatic cancer by alpha-enolase, a novel pancreatic ductal adenocarcinoma-associated antigen

Pancreatic ductal adenocarcinoma (PDAC) is a fatal disease with a very poor 5-year survival rate. alpha-Enolase is a glycolytic enzyme that also acts as a surface plasminogen receptor. We find that it is overexpressed in PDAC and present on the cell surface of PDAC cell lines. The clinical correlation of its expression with tumor status has been reported for lung and hepatocellular carcinoma. We have previously demonstrated that sera from PDAC patients contain IgG autoantibodies to alpha-enolase. The present work was intended to assess the ability of alpha-enolase to induce antigen-specific T cell responses. We show that alpha-enolase-pulsed dendritic cells (DC) specifically stimulate healthy autologous T cells to proliferate, secrete IFN-gamma and lyse PDAC cells but not normal cells. In vivo, alpha-enolase-specific T cells inhibited the growth of PDAC cells in immunodeficient mice. In 8 out of 12 PDAC patients with circulating IgG to alpha-enolase, the existence of alpha-enolase-specific T cells was also demonstrated. Taken as a whole, these results indicate that alpha-enolase elicits a PDAC-specific, integrated humoral and cellular response. It is thus a promising and clinically relevant molecular target candidate for immunotherapeutic approaches as new adjuvants to conventional treatments in pancreatic cancer.

Activin A induces Langerhans cell differentiation in vitro and in human skin explants

Langerhans cells (LC) represent a well characterized subset of dendritic cells located in the epidermis of skin and mucosae. In vivo, they originate from resident and blood-borne precursors in the presence of keratinocyte-derived TGFbeta. In vitro, LC can be generated from monocytes in the presence of GM-CSF, IL-4 and TGFbeta. However, the signals that induce LC during an inflammatory reaction are not fully investigated. Here we report that Activin A, a TGFbeta family member induced by pro-inflammatory cytokines and involved in skin morphogenesis and wound healing, induces the differentiation of human monocytes into LC in the absence of TGFbeta. Activin A-induced LC are Langerin+, Birbeck granules+, E-cadherin+, CLA+ and CCR6+ and possess typical APC functions. In human skin explants, intradermal injection of Activin A increased the number of CD1a+ and Langerin+ cells in both the epidermis and dermis by promoting the differentiation of resident precursor cells. High levels of Activin A were present in the upper epidermal layers and in the dermis of Lichen Planus biopsies in association with a marked infiltration of CD1a+ and Langerin+ cells. This study reports that Activin A induces the differentiation of circulating CD14+ cells into LC. Since Activin A is abundantly produced during inflammatory conditions which are also characterized by increased numbers of LC, we propose that this cytokine represents a new pathway, alternative to TGFbeta, responsible for LC differentiation during inflammatory/autoimmune conditions.

Postburn Scars: An Update

Burn wounds give rise to the largest scars we can find in human pathology, influencing patients' quality of life. Despite the improved knowledge on pathophysiology, efficacy of the various treatments remains unsatisfactory. In this short review recent literature is examined with a focus on recent data on postburn pathological scars epidemiology and risk factors, which underline the high prevalence and the long evolution, pointing to identify this illness as a systemic inflammatory one, more frequent in women and in those of younger age, regulated by local factors relevant in wound healing.

Variants of parvovirus B19: bioinformatical evaluation of nested PCR assays

Variants of parvovirus B19 are currently grouped into three genotypes: 1 (reference B19 strains), 2 and 3. It has been evidenced that isolate K71 of genotype 2 is more prevalent in skin than the conventional B19 genotype 1. In this study we investigated the detection of parvovirus B19 genotypes by using two nested PCRs and evaluating the suitability of these assays by BLAST search of parvovirus isolates. Subsequently, we analyze the present genotypes in skin biopsies. The two nested PCRs employed in this study allow to amplify 41 isolates as confirmed by bioinformatical validation. The molecular epidemiological characterization of our casistics confirmed the presence of isolate K71 in human skin.

Reciprocal regulation of p63 by C/EBP delta in human keratinocytes

Background

Genetic experiments have clarified that p63 is a key transcription factor governing the establishment and maintenance of multilayered epithelia. Key to our understanding of p63 strategy is the identification of target genes. We perfomed an RNAi screening in keratinocytes for p63, followed by profiling analysis.

Results

C/EBPδ, member of a family with known roles in differentiation pathways, emerged as a gene repressed by p63. We validated C/EBPδ as a primary target of ΔNp63α by RT-PCR and ChIP location analysis in HaCaT and primary cells. C/EBPδ is differentially expressed in stratification of human skin and it is up-regulated upon differentiation of HaCaT and primary keratinocytes. It is bound to and activates the ΔNp63 promoter. Overexpression of C/EBPδ leads to alteration in the normal profile of p63 isoforms, with the emergence of ΔNp63β and γ, and of the TA isoforms, with different kinetics. In addition, there are changes in the expression of most p63 targets. Inactivation of C/EBPδ leads to gene expression modifications, in part due to the concomitant repression of ΔNp63α. Finally, C/EBPδ is found on the p63 targets in vivo by ChIP analysis, indicating that coregulation is direct.

Conclusion

Our data highlight a coherent cross-talk between these two transcription factors in keratinocytes and a large sharing of common transcriptional targets.

Imbalance between activin A and follistatin drives postburn hypertrophic scar formation in human skin

Hypertrophic scarring is a skin disorder characterized by persistent inflammation and fibrosis that may occur after wounding or thermal injury. Altered production of cytokines and growth factors, such as TGF-beta, play an important role in this process. Activin A, a member of the TGF-beta family, shares the same intra-cellular Smad signalling pathway with TGF-beta, but binds to its own specific transmembrane receptors and to follistatin, a secreted protein that inhibits activin by sequestration. Recent studies provide evidences of a novel role of activin A in inflammatory and repair processes. The aim of this study was to evaluate the importance of activin A and follistatin expression in the different phases of scar evolution. Immunostaining of sections obtained from active phase hypertrophic scars (AHS) revealed the presence of a high number of alpha-SMA(+) myofibroblasts and DC-SIGN(+) dendritic cells coexpressing activin A. Ex-vivo AHS fibroblasts produced more activin and less follistatin than normal skin or remission phase hypertrophic scar (HS) fibroblasts, both in basal conditions and upon TGF-betas stimulation. We demonstrate that fibroblasts do express activin receptors, and that this expression is not affected by TGF-betas. Treatment of HS fibroblasts with activin A induced Akt phosphorylation, promoted cell proliferation, and enhanced alpha-SMA and type I collagen expression. Follistatin reduced proliferation and suppressed activin-induced collagen expression. These results indicate that the activin/follistatin interplay has a role in HS formation and evolution. The impact of these observations on the understanding of wound healing and on the identification of new therapeutic targets is discussed.

Identification of new p63 targets in human keratinocytes

p63 is a transcription factor involved in the development of ectodermal tissues, including limb, skin and, in general, multilayered epithelia. We identified both activated and repressed genes in human keratinocytes via gene expression profiling of p63-depleted cells and validated 21 new primary targets by RT-PCR and ChIP location analysis. The p63 isoforms differentially activate or repress selected promoters. ChIPs in primary keratinocytes indicate that p63 targets are generally shared with p53, but some are p63-specific. Several growth suppressors are among repressed genes. The newly identified genes belong to pathways of growth and differentiation and are regulated in HaCaT differentiation and in stratification of human skin.

New p63 targets in keratinocytes identified by a genome-wide approach

p63 is a developmentally regulated transcription factor related to p53. It is involved in the development of ectodermal tissues, including limb, skin and in general, multilayered epithelia. The DeltaNp63alpha isoform is thought to play a 'master' role in the asymmetric division of epithelial cells. It is also involved in the pathogenesis of several human diseases, phenotypically characterized by ectodermal dysplasia. Our understanding of transcriptional networks controlled by p63 is limited, owing to the low number of bona fide targets. To screen for new targets, we employed chromatin immunoprecipitation from keratinocytes (KCs) coupled to the microarray technology, using both CpG islands and promoter arrays. The former revealed 96 loci, the latter yielded 85 additional genes. We tested 40 of these targets in several functional assays, including: (i) in vivo binding by p63 in primary KCs; (ii) expression analysis in differentiating HaCaT cells and in cells overexpressing DeltaNp63alpha; (iii) promoter transactivation and (iv) immunostaining in normal tissues, confirming their regulation by p63. We discovered several new specific targets whose functional categorization links p63 to cell growth and differentiation.

Evaluation of donor skin viability: fresh and cryopreserved skin using tetrazolioum salt assay

Cell viability assessment in allograft skin is an essential step to ensure a supply of good quality allograft skin for clinical repair of wounds. It is widely recognised that 'take' of allografts is strongly influenced grafted by tissue viability. The aim of this study was to set-up storage protocols that maintain high viability of the allograft after harvest, treatment and storage. In this study, the viability of post-mortem allografts (n=350) harvested from 35 different donors, was investigated using the MTT salt assay. The conditions of preparation and storage of the allograft included: 1. Fresh skin samples (about 12, 30, and 60h after harvesting). 2. The same specimens (stored at 4 and 37 degrees C) tested for at least 1 month. 3. Samples after cryopreservation and thawing. 4. Thawed specimens tested daily for at least 6 days. Parallel histomorphological analysis performed, under each of these conditions, showed a correlation between changes in structure and changes in viability as measured by the MTT quantitative assay. The viability index (VI) of skin is expressed as the ratio between the optical density (O.D.) produced in the MTT assay by the skin sample and its weight in grams. The percentage viability index is the ratio of the VI of the fresh sample (considered as 100% viability) and the value of specimens from the same harvest batch after storage or cryopreservation. The results indicated that samples tested within 12-30h from harvesting have an average viability index of about 75 with little variation. Samples tested within 60h have an average viability index of 40, showing a viability decrease of about 50%. A protocol to treat skin within a maximum of 30h was, therefore, set-up. The data suggested that skin stored at 37 degrees C, undergoes a viability increase during the first 2 days after harvesting. However, the viability under these conditions then decreased very quickly. After 6 days of preservation at this temperature the samples were no longer viable (PVI = 0). The tissue structure started to become damaged after 3 days. On the other hand, skin stored at 4 degrees C, showed a very slow viability decrease. After 15 days, viability was still almost 25% of the fresh sample. The tissue architecture showed no signs of damage under these conditions until day 7 from harvesting. MTT analysis was performed on the specimens cryopreserved with DMSO at 10%. These measurements were compared to viability assessment of the same fresh skin samples (considered as 100%) that were analysed within 30h from harvesting. The average PVI of thawed skin was 54% of the fresh sample. This result demonstrates that the viability of cryopreserved skin is comparable to the viability of fresh skin stored at 4 degrees C for 4 days. The PVI of thawed skin samples decreased dramatically within 24h, and had reached 0% within 6 days.

The role of quality control in a skin bank: tissue viability determination

New surgical procedures requiring viable skin have increased rapidly over the last few years. The cell viability assessment in allograft skin is a major step forward in burn treatment, since it is well-known that taking is correlated with grafted tissue viability. Various methods, both qualitative and quantitative, are currently used. Although qualitative assays (histomorphology, immunocytochemistry) are routinely performed in our laboratory, there arose a need to set up a standardised quantitative assay in an attempt to obtain a cut-off value so that the skin sample could be determined valid or not for grafting. Therefore, two different tetrazolium salt compounds MTT and WST-1, were compared in order to determine their efficacy in the evaluation of tissue viability. Several experimental conditions were analysed: 1- cellular cultures of keratinocytes and fibroblasts, 2- fresh skin tissue samples, 3- the same specimen tested daily for at least 2 weeks, 4- after cryopreservation and thawing. Viable cells were analysed by the cleavage of tetrazolium salts to formazan by cellular enzymes. The formazan dye produced by metabolically active cells was then quantified by measuring the absorbance of the dye solution at the appropriate wavelength. It was seen that WST-1 is easier to handle, more stable, has a wider linear range, accelerated colour development and is more sensitive than MTT on fresh specimens and cell suspension. However, after 72 hours of storage at 4 degrees C, most of the WST-1 tested specimens no longer gave any absorbance signal, whilst MTT specimens were seen to give a signal for more than two weeks. Moreover, after thawing WST-1 tested samples were almost negative, whilst MTT samples continued to give strong signals. In conclusion, WST-1 assay offers rapid and precise results as to the cell viability of fresh allografts and cell cultures, whilst the MTT method is much more useful in establishing viability after long conservation and cryopreservation. In our clinical experience, allografts transplanted at 72 hr post-harvesting or after cryopreservation showed a mean of take more than of 80%, demonstrating that the MTT system is more reliable for the determination of allograft viability. Studies are ongoing with larger clinical cohorts to establish the precise cut-off value for skin graft validation.

RR interval variation, sympathetic skin reflex and QT dispersion in the assessment of autonomic function in peripheral neuropathy

In recent years, two simple non-invasive tests, sympathetic skin response (SSR) and RR interval variation (RRIV) have been used to assess autonomic function (Wang et al., 1994; Drory et al., 1995; Chassande et al., 1996; Bordet et al., 1996; Spitzer et al., 1997). Their easy performance by an electromyographic (EMG) machine and successful clinical correlation (Shahani et al., 1990) have made them routine in autonomic assessment in several EMG laboratories. More recently QT dispersion on electrocardiogram (ECG) has been shown to have increased in patients with diabetic neuropathy and several autonomic dysfunctions (Wei et al., 1995; Lengyel et al., 1997; Langen et al., 1997; Axelrod et al., 1997). In order to evaluate the diagnostic value of the RR interval variation, sympathetic skin response and QT dispersion combined, we performed the three tests on a group of 37 patients with several peripheral neuropathies with and without clinical signs of dysautonomia. All patients were studied using an electromyograph (EMG). The results of the SSR, RRIV and QT dispersion combined have shown abnormal values in all patients with neuropathy and clinical dysautonomia and in some patients without clinical signs of dysautonomia, suggesting a subclinical autonomic dysfunction. The principal finding of this study is that the evaluation of the RRIV, SSR and QT dispersion combined may contribute to the assessment of dysautonomia in patients with somatic neuropathy and that they may be currently performed by an electromyograph.