Defective glucose and lipid metabolism in rheumatoid arthritis is determined by chronic inflammation in metabolic tissues.

BACKGROUND: Rheumatoid arthritis (RA) patients are at increased risk of insulin resistance (IR); however, the specific mechanisms mediating this association are currently unknown. OBJECTIVE: To investigate whether the inflammatory activity associated with RA accounts for the observed defective glucose metabolism and lipid metabolism in these patients. METHODS: We followed two main strategies: (i) extensive metabolic profiling of a RA cohort of 100 patients and 50 healthy control subjects and (ii) mechanistic studies carried out in both a collagen-induced arthritis mouse model and 3T3-L1 adipocytes treated with conditioned serum from RA patients. RESULTS: Following the exclusion of obese and diabetic subjects, data from RA patients demonstrated a strong link between the degree of systemic inflammation and the development of IR. These results were strengthened by the observation that induction of arthritis in mice resulted in a global inflammatory state characterized by defective carbohydrate and lipid metabolism in different tissues. Adipose tissue was most susceptible to the RA-induced metabolic alterations. These metabolic effects were confirmed in adipocytes treated with serum from RA patients. CONCLUSIONS: Our results show that the metabolic disturbances associated with RA depend on the degree of inflammation and identify inflammation of adipose tissue as the initial target leading to IR and the associated molecular disorders of carbohydrate and lipid homeostasis. Thus, we anticipate that therapeutic strategies based on tighter control of inflammation and flares could provide promising approaches to normalize and/or prevent metabolic alterations associated with RA.

Diagnostic potential of NETosis-derived products for disease activity, atherosclerosis and therapeutic effectiveness in Rheumatoid Arthritis patients.

OBJECTIVES: 1) To assess the association of NETosis and NETosis-derived products with the activity of the disease and the development of cardiovascular disease in RA; 2) To evaluate the involvement of NETosis on the effects of biologic therapies such as anti-TNF alpha (Infliximab) and anti-IL6R drugs (Tocilizumab). METHODS: One hundred and six RA patients and 40 healthy donors were evaluated for the occurrence of NETosis. Carotid-intimae media thickness was analyzed as early atherosclerosis marker. Inflammatory and oxidative stress mediators were quantified in plasma and neutrophils. Two additional cohorts of 75 RA patients, treated either with Infliximab (n = 55) or Tocilizumab (n = 20) for six months, were evaluated. RESULTS: NETosis was found increased in RA patients, beside myeloperoxidase and neutrophil elastase protein levels. Cell-free nucleosomes plasma levels were elevated, and strongly correlated with the activity of the disease and the positivity for autoantibodies, alongside inflammatory and oxidative profiles in plasma and neutrophils. Moreover, ROC analyses showed that cell-free nucleosomes levels could identify RA patients showing early atherosclerosis with high specificity. RA patients treated either with IFX or TCZ for six months exhibited decreased generation of NETs. Concomitantly, clinical parameters and serum markers of inflammation were found reduced. Mechanistic in vitro analyses showed that inhibition of NETs extrusion by either DNase, IFX or TCZ, further abridged the endothelial dysfunction and the activation of immune cells, thus influencing the global activity of the vascular system. CONCLUSIONS: NETosis-derived products may have diagnostic potential for disease activity and atherosclerosis, as well as for the assessment of therapeutic effectiveness in RA.

Real-world cost-effectiveness of infliximab, etanercept and adalimumab in rheumatoid arthritis patients: results of the CREATE registry.

Biological drugs have proven efficacy and effectiveness in treatment of rheumatoid arthritis (RA), although none has been shown to be superior. Few studies have evaluated the cost-effectiveness of biological drugs in real-life clinical conditions. The objective of this study was to compare the cost-effectiveness of infliximab, etanercept and adalimumab in achieving clinical remission (DAS28 < 2.6) when used as initial biological therapy. Patients were diagnosed with RA who began treatment with infliximab, etanercept or adalimumab in the Reina Sofia Hospital (Cordoba, Spain) between January 1, 2007, and December 31, 2012. Effectiveness was measured as the percentage of patients who achieved clinical remission after 2 years. The cost analysis considered the use of direct health resources (perspective of the healthcare system). Cost-effectiveness was calculated by dividing the total mean cost of each treatment by the percentage of patients who achieved remission. One hundred and thirty patients were included: 55 with infliximab, 44 with adalimumab and 31 with etanercept. After 2 years, 45.2 % of patients with adalimumab achieved clinical remission, versus 29.1 % with infliximab (p = 0.133) and 22.7 % with etanercept (p = 0.040), with no differences between etanercept and infliximab (p = 0.475). The average total cost at 2 years was €29,858, €25,329 and €23,309 for adalimumab, infliximab and etanercept, respectively, while the mean cost (95 %CI) to achieve remission was €66,057 (48,038­84,076), €87,040 (78,496­95,584) and €102,683 (94,559­110,807), respectively. Adalimumab was more efficient than etanercept (p < 0.001) and infliximab (p = 0.026), with no differences between etanercept and infliximab (p = 0.086). Adalimumab was the most cost-effective treatment in achieving clinical remission in real-life clinical conditions in RA patients during the study period.

Cost-effectiveness of clinical remission by treat to target strategy in established rheumatoid arthritis: results of the CREATE registry.

To analyse the cost-effectiveness, in daily clinical practice, of the strategy of treating to the target of clinical remission (CR) in patients with established rheumatoid arthritis (RA), after 2 years of treatment with biological therapy. Adult patients with established RA were treated with biological therapy and followed up for 2 years by a multidisciplinary team responsible for their clinical management. Treatment effectiveness was evaluated by the DAS28 score. The direct costs incurred during this period were quantified from the perspective of the healthcare system. We calculated the cost-effectiveness of obtaining a DAS28 < 2.6, considered as CR. The study included 144 RA patients treated with biological therapies. After 2 years of treatment, 32.6% of patients achieved CR. The mean cost of achieving CR at 2 years was 79,681 ± 38,880 euros. The strategy of treatment to the target of CR is considered the most effective, but in actual clinical practice in patients with established RA, it has a high cost.

Inter-rater reliability of clinical mobility measures in ankylosing spondylitis.

BACKGROUND: Several measurements are often used in daily clinical practice in the assessment of Ankylosing Spondylitis (AS) patients. The Assessment in SpondyloArthiritis International Society (ASAS) recommend in its core set: chest expansion modified Schöber test, Occiput to wall distance, lateral lumbar flexion, cervical rotation and The Bath Ankylosing Spondylitis Metrology Index (BASMI). BASMI also includes five measurements, some of them recommended by ASAS. Three versions of BASMI have been published with different scales and intervals for each component of the index. Though studies about reliability of these measurements are needed. The aim of this study was to analyze inter-rater reliability of recommended spinal mobility measures in AS. METHODS: We examined reproducibility of spinal mobility measurements on 33 AS patients performed by two experienced rheumatologists in the same day. Descriptive statistics, Intraclass Correlation Coefficients (ICC), and Smallest Detectable Difference (SDD) using the Bland-Altman criteria were obtained for all the measurements. RESULTS: Chest expansion showed the lowest value of ICC (0.66) and occiput-wall the highest (0.97). SDD was 2.43 units for BASMI2 and 1.27 units for BASMI10. CONCLUSIONS: Reliability according to ICC was moderate to high in all measurements. BASMI10, instead BASMI2, must be used: measurements used to calculate are the same but there is better reliability. Inter-rater variation, expressed as SDD, must be taken in account: smaller improvements do not demonstrate the efficacy of treatment because they can be due to experimental error and not to the treatment itself.

Enhanced γ-Ray Emission from Neutron Unbound States Populated in ß Decay.

Total absorption spectroscopy is used to investigate the ß-decay intensity to states above the neutron separation energy followed by γ-ray emission in (87,88)Br and (94)Rb. Accurate results are obtained thanks to a careful control of systematic errors. An unexpectedly large γ intensity is observed in all three cases extending well beyond the excitation energy region where neutron penetration is hindered by low neutron energy. The γ branching as a function of excitation energy is compared to Hauser-Feshbach model calculations. For (87)Br and (88)Br the γ branching reaches 57% and 20%, respectively, and could be explained as a nuclear structure effect. Some of the states populated in the daughter can only decay through the emission of a large orbital angular momentum neutron with a strongly reduced barrier penetrability. In the case of neutron-rich (94)Rb the observed 4.5% branching is much larger than the calculations performed with standard nuclear statistical model parameters, even after proper correction for fluctuation effects on individual transition widths. The difference can be reconciled by introducing an enhancement of 1 order of magnitude in the photon strength to neutron strength ratio. An increase in the photon strength function of such magnitude for very neutron-rich nuclei, if it proves to be correct, leads to a similar increase in the (n,γ) cross section that would have an impact on r process abundance calculations.

Total Absorption Spectroscopy Study of (92)Rb Decay: A Major Contributor to Reactor Antineutrino Spectrum Shape.

The antineutrino spectra measured in recent experiments at reactors are inconsistent with calculations based on the conversion of integral beta spectra recorded at the ILL reactor. (92)Rb makes the dominant contribution to the reactor antineutrino spectrum in the 5-8 MeV range but its decay properties are in question. We have studied (92)Rb decay with total absorption spectroscopy. Previously unobserved beta feeding was seen in the 4.5-5.5 region and the GS to GS feeding was found to be 87.5(25)%. The impact on the reactor antineutrino spectra calculated with the summation method is shown and discussed.

Validity of the ankylosing spondylitis disease activity score (ASDAS) in patients with early spondyloarthritis from the Esperanza programme.

OBJECTIVES: To evaluate the validity of the Ankylosing Spondylitis Disease Activity Score (ASDAS) in early spondyloarthritis (SpA) in comparison with conventional clinical measures of disease activity. METHODS: Six hundred and seventy-six incident cases of early SpA from the Esperanza programme were included. Patients were categorised into high and low disease activity states based on patient and physician global assessment scores and on the physician's decision to start treatment with a disease-modifying antirheumatic drug or tumour necrosis factor blocker. The discriminant ability of ASDAS-C-reactive protein (CRP) and ASDAS-erythrocyte sedimentation rate (ESR) was tested using standardised mean differences between patients with high and low disease activity. Convergent validity was tested by Pearson correlation between ASDAS versions and other measures of disease activity. RESULTS: ASDAS-ESR and ASDAS-CRP showed good correlation with BASDAI (r=0.79 and 0.74, respectively). Both indices correlated well with the patient global assessment (r=0.70 in both indices) and moderately with the physician global score (r=0.46 and 0.47, respectively). CRP and ESR showed poor correlation with patient- and physician-derived measures. ASDAS performed similarly across the global SpA sample, ankylosing spondylitis (AS), non-radiographic axial SpA and peripheral SpA. CONCLUSIONS: ASDAS performed as a valid activity score even being slightly better than the Bath Ankylosing Spondylitis Disease Activity Index in its ability to discriminate between high and low disease activity in early SpA. ASDAS performed similarly in AS, early forms of SpA, non-radiographic axial SpA and peripheral SpA.

Targeting gp130 to prevent inflammation and promote insulin action.

Obesity and type 2 diabetes are now the most prevalent metabolic diseases in the Western world and the development of new strategies to treat these metabolic diseases is most warranted. Obesity results in a state of chronic low-grade inflammation in metabolically active tissues such as the liver, adipose tissue, brain and skeletal muscle. Work in our laboratory has focussed on the role of the cytokine interleukin-6 (IL)-6 and other IL-6-like cytokines that signal through the gp130 receptor complex. We have focussed on the role of blocking IL-6 trans-signalling to prevent inflammation on the one hand, and activating membrane-bound signalling to promote insulin sensitivity on the other hand. Since the cloning of the IL-6 gene nearly 30 years ago, a pattern has emerged associating IL-6 with a number of diseases associated with inflammation including rheumatoid arthritis (RA), Crohn's disease and several cancers. Accordingly, tocilizumab, an IL-6 receptor-inhibiting monoclonal antibody, is now useful for the treatment of RA. However, this may not be the most optimal strategy to block inflammation associated with IL-6 and may result in unwanted side effects that, paradoxically, could actually promote metabolic disease.

Clinical features and immune mechanisms directly linked to the altered liver function in patients with rheumatoid arthritis.

BACKGROUND: The aim of this study was to explore the impact of arthritis on liver function using different approaches in vivo and in vitro. METHODS: A cross-sectional study was performed on 330 non-obese/non-T2DM subjects: 180 RA patients, 50 NAFLD non-RA patients, and 100 healthy donors (HDs). A longitudinal study was conducted on 50 RA patients treated with methotrexate for six months. Clinical and laboratory parameters and markers of liver disease were collected. Mechanistic studies were carried out in both the CIA mouse model and hepatocytes treated with anti-citrullinated protein antibodies (ACPAs). RESULTS: RA patients have an increased risk of suffering from liver disease independent of obesity or T2DM. This risk was associated with factors such as insulin resistance, autoantibodies, inflammation, and component C3. Methotrexate treatment for six months was associated with liver abnormalities in those newly-diagnosed patients having CV risk factors. ACPAs induced a defective hepatocyte function, promoting IR and inflammation. The induction of arthritis in mice caused the infiltration of immune cells in the liver and increased inflammatory, apoptotic, and fibrotic processes. CONCLUSION: RA patients may experience mild to moderate liver inflammation due to the infiltration of T, B cells, and macrophages, and the action of ACPAs. This is independent of obesity or diabetes and linked to systemic inflammation, and disease activity levels. The negative effects of methotrexate on liver function could be restricted to the concomitant presence of cardiovascular risk factors.

Decoding clinical and molecular pathways of liver dysfunction in Psoriatic Arthritis: Impact of cumulative methotrexate doses.

BACKGROUND: The occurrence of liver abnormalities in Psoriatic Arthritis (PsA) has gained significant recognition. Identifying key factors at the clinical and molecular level can help to detect high-risk patients for non-alcoholic fatty liver disease in PsA. OBJECTIVES: to investigate the influence of PsA and cumulative doses of methotrexate on liver function through comprehensive in vivo and in vitro investigations. METHODS: A cross-sectional study involving 387 subjects was conducted, 200 patients with PsA, 87 NAFLD-non-PsA patients, and 100 healthy donors (HDs), age and sex-matched. Additionally, a retrospective longitudinal study was carried out, including 83 PsA patients since initiation with methotrexate. Detailed clinical, and laboratory parameters along with liver disease risk were analyzed. In vitro, experiments with hepatocyte cell line (HEPG2) were conducted. RESULTS: PsA patients present increased liver disease risk associated with the presence of cardiometabolic comorbidities, inflammatory markers, onychopathy, and psoriasis. The treatment with PsA serum on hepatocytes encompassed inflammatory, fibrotic, cell stress, and apoptotic processes. At the molecular level, methotrexate impacts liver biology, although the cumulative doses did not affect those alterations, causing any potential damage to liver function at the clinical level. Finally, anti-PDE-4 or anti-JAK decreased the inflammatory profile induced by PsA serum on hepatocytes. CONCLUSION: 1)This study identifies the complex link between liver disease risk, comorbidities, and disease-specific features in PsA patients. 2)Methotrexate dose in PsA patients had no significant effect on liver parameters, confirmed by hepatocyte in vitro studies. 3)Anti-PDE-4 and anti-JAK therapies show promise in reducing PsA serum-induced hepatocyte activation, potentially aiding liver complication management.

Skeletal muscle-specific overproduction of constitutively activated c-Jun N-terminal kinase (JNK) induces insulin resistance in mice.

AIMS/HYPOTHESIS: Although skeletal muscle insulin resistance has been associated with activation of c-Jun N-terminal kinase (JNK), whether increased JNK activity causes insulin resistance in this organ is not clear. In this study we examined the metabolic consequences of isolated JNK phosphorylation in muscle tissue. METHODS: Plasmids containing genes encoding a wild-type JNK1 (WT-JNK) or a JNK1/JNKK2 fusion protein (rendering JNK constitutively active; CA-Jnk) were electroporated into one tibialis anterior (TA) muscle of C57Bl/6 mice, with the contralateral TA injected with an empty vector (CON) to serve as a within-animal control. RESULTS: Overproduction of WT-JNK resulted in a modest (~25%) increase in phosphorylation (Thr(183)/Tyr(185)) of JNK, but no differences were observed in Ser(307) phosphorylation of insulin receptor substrate 1 (IRS-1) or total IRS-1 protein, nor in insulin-stimulated glucose clearance into the TA muscle when comparing WT-JNK with CON. By contrast, overexpression of CA-Jnk, which markedly increased the phosphorylation of CA-JNK, also increased serine phosphorylation of IRS-1, markedly decreased total IRS-1 protein, and decreased insulin-stimulated phosphorylation of the insulin receptor (Tyr(1361)) and phosphorylation of Akt at (Ser(473) and Thr(308)) compared with CON. Moreover, overexpression of CA-Jnk decreased insulin-stimulated glucose clearance into the TA muscle compared with CON and these effects were observed without changes in intramuscular lipid species. CONCLUSIONS/INTERPRETATION: Constitutive activation of JNK in skeletal muscle impairs insulin signalling at the level of IRS-1 and Akt, a process which results in the disruption of normal glucose clearance into the muscle.

2010 update of the ASAS/EULAR recommendations for the management of ankylosing spondylitis.

This first update of the ASAS/EULAR recommendations on the management of ankylosing spondylitis (AS) is based on the original paper, a systematic review of existing recommendations and the literature since 2005 and the discussion and agreement among 21 international experts, 2 patients and 2 physiotherapists in a meeting in February 2010. Each original bullet point was discussed in detail and reworded if necessary. Decisions on new recommendations were made - if necessary after voting. The strength of the recommendations (SOR) was scored on an 11-point numerical rating scale after the meeting by email. These recommendations apply to patients of all ages that fulfill the modified NY criteria for AS, independent of extra-articular manifestations, and they take into account all drug and non-drug interventions related to AS. Four overarching principles were introduced, implying that one bullet has been moved to this section. There are now 11 bullet points including 2 new ones, one related to extra-articular manifestations and one to changes in the disease course. With a mean score of 9.1 (range 8-10) the SOR was generally very good.

Abdominal cystic lymphangiomas in pediatrics: surgical approach and outcomes.

BACKGROUND: Abdominal Cystic lymphangiomas (ACL) are uncommon benign masses usually presented during infancy. Although extremely rare, they may cause complications; therefore, the recommended therapy is surgical excision. The purpose of this study is to report our experience with the diagnosis and surgical treatment of ACL in pediatric population. MATERIAL AND METHODS: From January 1994 to December 2009, 10 patients (6 females; 4 males) with diagnostic confirmation of ACL were retrospectively included in study. Children's age ranged between 9 months and 8 years (mean age at diagnosis was 2.5 years). Clinical presentation, cyst location, imaging studies employed, surgical approach and pathologic features were analyzed. RESULTS: The most common symptom was abdominal pain but three cases were incidentally detected. One case had presented with acute abdomen after traumatic haemorrhage of the tumor. All patients were diagnosed with ultrasonography as first-line radiological study. MRI was used in last three cases. At surgery, concomitant bowel resection was necessary in 3 children. Location of the lesion (omentum, mesentery) did not influence the outcome but surgery was more difficult (operative time over three hours) in patients with lymphangioma affecting mesentery of the jejunum. Mean hospital stay after surgery was 6.7 days. Mean follow-up was 5.1 years. No recurrence of the cystic lymphangioma was noticed during follow-up. One case developed an intestinal occlusion due to bowel adhesions 1 year after surgery. CONCLUSIONS: ACL usually affect infants and young children and may present with spectrum of symptoms from an incidental finding to an acute life-threatening abdominal obstruction. Complete excision of the tumor is a safe and effective method in the management of ACL in pediatric population. Surgery is mandatory to avoid potential complications.

New criteria for inflammatory back pain in patients with chronic back pain: a real patient exercise by experts from the Assessment of SpondyloArthritis international Society (ASAS).

OBJECTIVE: Inflammatory back pain (IBP) is an important clinical symptom in patients with axial spondyloarthritis (SpA), and relevant for classification and diagnosis. In the present report, a new approach for the development of IBP classification criteria is discussed. METHODS: Rheumatologists (n = 13) who are experts in SpA took part in a 2-day international workshop to investigate 20 patients with back pain and possible SpA. Each expert documented the presence/absence of clinical parameters typical for IBP, and judged whether IBP was considered present or absent based on the received information. This expert judgement was used as the dependent variable in a logistic regression analysis in order to identify those individual IBP parameters that contributed best to a diagnosis of IBP. The new set of IBP criteria was validated in a separate cohort of patients (n = 648). RESULTS: Five parameters best explained IBP according to the experts. These were: (1) improvement with exercise (odds ratio (OR) 23.1); (2) pain at night (OR 20.4); (3) insidious onset (OR 12.7); (4) age at onset <40 years (OR 9.9); and (5) no improvement with rest (OR 7.7). If at least four out of these five parameters were fulfilled, the criteria had a sensitivity of 77.0% and specificity of 91.7% in the patients participating in the workshop, and 79.6% and 72.4%, respectively, in the validation cohort. CONCLUSION: This new approach with real patients defines a set of IBP definition criteria using overall expert judgement on IBP as the gold standard. The IBP experts' criteria are robust, easy to apply and have good face validity.

The development of Assessment of SpondyloArthritis international Society classification criteria for axial spondyloarthritis (part II): validation and final selection.

OBJECTIVE: To validate and refine two sets of candidate criteria for the classification/diagnosis of axial spondyloarthritis (SpA). METHODS: All Assessment of SpondyloArthritis international Society (ASAS) members were invited to include consecutively new patients with chronic (> or =3 months) back pain of unknown origin that began before 45 years of age. The candidate criteria were first tested in the entire cohort of 649 patients from 25 centres, and then refined in a random selection of 40% of cases and thereafter validated in the remaining 60%. RESULTS: Upon diagnostic work-up, axial SpA was diagnosed in 60.2% of the cohort. Of these, 70% did not fulfil modified New York criteria and, therefore, were classified as having "non-radiographic" axial SpA. Refinement of the candidate criteria resulted in new ASAS classification criteria that are defined as: the presence of sacroiliitis by radiography or by magnetic resonance imaging (MRI) plus at least one SpA feature ("imaging arm") or the presence of HLA-B27 plus at least two SpA features ("clinical arm"). The sensitivity and specificity of the entire set of the new criteria were 82.9% and 84.4%, and for the imaging arm alone 66.2% and 97.3%, respectively. The specificity of the new criteria was much better than that of the European Spondylarthropathy Study Group criteria modified for MRI (sensitivity 85.1%, specificity 65.1%) and slightly better than that of the modified Amor criteria (sensitivity 82.9, specificity 77.5%). CONCLUSION: The new ASAS classification criteria for axial SpA can reliably classify patients for clinical studies and may help rheumatologists in clinical practice in diagnosing axial SpA in those with chronic back pain. TRIAL REGISTRATION NUMBER: NCT00328068.

The development of Assessment of SpondyloArthritis international Society classification criteria for axial spondyloarthritis (part I): classification of paper patients by expert opinion including uncertainty appraisal.

OBJECTIVE: Non-radiographic axial spondyloarthritis (SpA) is characterised by a lack of definitive radiographic sacroiliitis and is considered an early stage of ankylosing spondylitis. The objective of this study was to develop candidate classification criteria for axial SpA that include patients with but also without radiographic sacroiliitis. METHODS: Seventy-one patients with possible axial SpA, most of whom were lacking definite radiographic sacroiliitis, were reviewed as "paper patients" by 20 experts from the Assessment of SpondyloArthritis international Society (ASAS). Unequivocally classifiable patients were identified based on the aggregate expert opinion in conjunction with the expert-reported level of certainty of their judgement. Draft criteria for axial SpA were formulated and tested using classifiable patients. RESULTS: Active sacroiliitis on magnetic resonance imaging (MRI) (odds ratio 45, 95% CI 5.3 to 383; p<0.001) was strongly associated with the classification of axial SpA. The knowledge of MRI findings led to a change in the classification of 21.1% of patients. According to the first set of candidate criteria (sensitivity 97.1%; specificity 94.7%) a patient with chronic back pain is classified as axial SpA in the presence of sacroiliitis by MRI or x rays in conjunction with one SpA feature or, if sacroilitiis is absent, in the presence of at least three SpA features. In a second set of candidate criteria, inflammatory back pain is obligatory in the clinical arm (sensitivity 86.1%; specificity 94.7%). CONCLUSION: The ASAS group has developed candidate criteria for the classification of axial SpA that include patients without radiographic sacroiliitis. The candidate criteria need to be validated in an independent international study.

Human mesenchymal stromal cells from adult and neonatal sources: comparative analysis of their morphology, immunophenotype, differentiation patterns and neural protein expression.

BACKGROUND: Bone marrow (BM) has been recognized as the main source of mesenchymal stromal cells (MSC); however, MSC have also been detected in umbilical cord blood (UCB) and placenta (PL). In the present study, we obtained MSC from these three sources and characterized them in a comparative manner. METHODS: MSC were obtained from BM, UCB and PL samples and analyzed to determine their morphology, cell-surface antigen (Ag) expression and differentiation potential. Particular emphasis was placed on the expression of neural markers. RESULTS: MSC were detected in 9/9, 11/104 and 5/5 samples from BM, UCB and PL, respectively. MSC populations comprised several morphologically distinct cell types, including neural-like cells. MSC were positive for 'mesenchymal' Ag (CD105, CD73 and CD90), although CD90 expression was very heterogeneous. Interestingly, CD13 expression was high in all three sources. In all cases, MSC showed osteogenic and chondrogenic differentiation; however, UCB MSC showed no adipogenic potential. Furthermore, MSC from UCB produced a different type of cartilage compared with MSC from BM and PL. It is noteworthy that in all three sources we detected the expression of neural proteins without any neural differentiation stimuli. A significant increase in the proportion of neural marker-positive MSC was observed in the presence of neural inducers. DISCUSSION: Our results indicate that PL may prove to be a more appropriate source for obtaining MSC than UCB, and suggest the possibility that a subpopulation of MSC may possess neural potential, which is favored by neural inducers.

Mesenchymal Stromal Cells from the Epidermis and Dermis of Psoriasis Patients: Morphology, Immunophenotype, Differentiation Patterns, and Regulation of T Cell Proliferation.

Psoriasis is a skin disease characterized by hyperproliferation of keratinocytes and chronic inflammation. Mesenchymal stem/stromal cells (MSCs) exhibit an immunoregulatory function that can be altered in the skin of these patients. However, to date, the presence and functional capacity of MSCs in the dermis and epidermis of patients with psoriasis have not been fully established. In the present study, we evaluated the presence of MSCs in the skin of patients by obtaining adherent cells from the dermis and epidermis of lesional and nonlesional areas and characterizing them in a comparative manner with corresponding cells obtained from the dermis (HD-MSCs) and epidermis (HE-MSCs) of healthy donors. We determined whether the adherent cells had immunophenotypic profiles and differentiation potentials that were characteristic of MSCs. In addition, we analyzed their immunosuppression function by evaluating their capacity to decrease T cell proliferation. Our results indicate the presence of MSCs in the dermis and epidermis of healthy donors and patients with psoriasis; adherent cells from all skin sources exhibited MSC characteristics, such as expression of CD73, CD90, and CD105 markers and a lack of hematopoietic and endothelial marker expression. However, the cell populations obtained showed differences in differentiation potential toward adipogenic, osteogenic, and chondrogenic lineages. In addition, we observed a low MSC obtention frequency in nonlesional epidermal samples (NLE-MSCs), which also showed alterations in morphology and proliferation rate. Interestingly, MSCs from both the nonlesional dermis (NLD-MSCs) and lesional dermis (LD-MSCs) showed higher HLA class I antigen (HLA-I) expression than HD-MSCs. Moreover, NLD-MSCs showed a low T cell proliferation suppression capacity. In summary, this study demonstrates the presence of MSCs in the epidermis and dermis of patients with psoriasis and suggests that such cells may favor the inflammatory process and thus psoriatic lesion development through high HLA-I expression and low immunosuppression capacity.