Preventive effects of early immunosuppressive treatment on the development of interstitial lung disease in systemic sclerosis.

BACKGROUND: Hypothesizing that early treatment yields improved prognosis, we aimed to investigate how the timing of immunosuppressive treatment relates to interstitial lung disease (ILD) development and the course of pulmonary function in systemic sclerosis (SSc). METHODS: A cohort was created using data from the EUSTAR database and Nijmegen Systemic Sclerosis cohort, including adult patients who started their first immunosuppressive treatment (ie mycophenolate mofetil, methotrexate, cyclophosphamide, tocilizumab or rituximab) after SSc diagnosis, and no signs of ILD on high-resolution CT. ILD-free survival and the course of forced vital capacity % predicted (ppFVC) were assessed for up to 5 years follow-up comparing patients who started early (disease duration ≤ 3 years) vs late with immunosuppression. RESULTS: 1052 patients met the eligibility criteria. The early treatment group (n = 547, 52%) showed a higher prevalence of male sex, diffuse cutaneous subtype (53.1% vs 36.5%), and anti-topoisomerase-I antibody (ATA, 51.1% vs 42.7%). Most patients were treated with methotrexate (60.1%), whereas only a few patients were treated with biologicals (1.7%). The incidence of ILD was 46.6% after mean (SD) 3.6(1.4) years; the hazards ratio for ILD in the early treatment group was 1.13 (95% CI: 0.93-1.38) after adjustment for confounders. PpFVC trajectories were comparable between groups. CONCLUSION: Our findings did not confirm a preventive role of early initiation of immunosuppressive therapy vs late initiation on ILD development. However, our findings should be interpreted with caution, considering the high inflammatory, ATA-positive enriched nature of the cohort, confounding by indication, and very few patients were treated with biologicals.

Oral 11ß-HSD1 inhibitor AZD4017 improves wound healing and skin integrity in adults with type 2 diabetes mellitus: a pilot randomized controlled trial.

BACKGROUND: Chronic wounds (e.g. diabetic foot ulcers) reduce the quality of life, yet treatments remain limited. Glucocorticoids (activated by the enzyme 11ß-hydroxysteroid dehydrogenase type 1, 11ß-HSD1) impair wound healing. OBJECTIVES: Efficacy, safety, and feasibility of 11ß-HSD1 inhibition for skin function and wound healing. DESIGN: Investigator-initiated, double-blind, randomized, placebo-controlled, parallel-group phase 2b pilot trial. METHODS: Single-center secondary care setting. Adults with type 2 diabetes mellitus without foot ulcers were administered 400 mg oral 11ß-HSD1 inhibitor AZD4017 (n = 14) or placebo (n = 14) bi-daily for 35 days. Participants underwent 3-mm full-thickness punch skin biopsies at baseline and on day 28; wound healing was monitored after 2 and 7 days. Computer-generated 1:1 randomization was pharmacy-administered. Analysis was descriptive and focused on CI estimation. Of the 36 participants screened, 28 were randomized. RESULTS: Exploratory proof-of-concept efficacy analysis suggested AZD4017 did not inhibit 24-h ex vivoskin 11ß-HSD1 activity (primary outcome; difference in percentage conversion per 24 h 1.1% (90% CI: -3.4 to 5.5) but reduced systemic 11ß-HSD1 activity by 87% (69-104%). Wound diameter was 34% (7-63%) smaller with AZD4017 at day 2, and 48% (12-85%) smaller after repeat wounding at day 30. AZD4017 improved epidermal integrity but modestly impaired barrier function. Minimal adverse events were comparable to placebo. Recruitment rate, retention, and data completeness were 2.9/month, 27/28, and 95.3%, respectively. CONCLUSION: A phase 2 trial is feasible, and preliminary proof-of-concept data suggests AZD4017 warrants further investigation in conditions of delayed healing, for example in diabetic foot ulcers. SIGNIFICANCE STATEMENT: Stress hormone activation by the enzyme 11ß-HSD type 1 impairs skin function (e.g. integrity) and delays wound healing in animal models of diabetes, but effects in human skin were previously unknown. Skin function was evaluated in response to treatment with a 11ß-HSD type 1 inhibitor (AZD4017), or placebo, in people with type 2 diabetes. Importantly, AZD4017 was safe and well tolerated. This first-in-human randomized, controlled, clinical trial found novel evidence that 11ß-HSD type 1 regulates skin function in humans, including improved wound healing, epidermal integrity, and increased water loss. Results warrant further studies in conditions of impaired wound healing, for example, diabetic foot ulcers to evaluate 11ß-HSD type 1 as a novel therapeutic target forchronic wounds.

Long-term effects of bronchopulmonary dysplasia on lung function: a pilot study in preschool children's cohort.

INTRODUCTION: Although the long term negative effects of bronchopulmonary dysplasia (BPD) are well known, follow-up studies of preterm infants with BPD into childhood are lacking. METHODS: Forty-two preschool children (age range 3-6 years) who were born before 32 weeks of gestational age and affected by BPD were enrolled. Pre-, peri-, and post-natal data were collected. During the follow up appointment complete physical examination and lung function (impulse oscillometry (IOS)) were recorded. The European Community Respiratory Health Survey (ECRHS) questionnaire was administered to all enrolled subjects. RESULTS: Thirty patients were included in the final analysis. The BPD group did not differ in comparison to the non-BPD group in terms of lung function (p > 0.05). By comparing all subjects enrolled, We detected extremely low-birth-weight (ELBW) infants with height-, weight-, and gender-related reference values and a significant trend of increasing resistance values (R5Hz, R5-20 Hz) and respiratory impedance (Z5Hz) (p < 0.05). No significant difference in bronchial reversibility test was observed among BPD non-BPD groups (p < 0.05). The frequency of gastroesophageal reflux disease was significantly higher in patients with BPD when compared to non-BPD group (p < 0.05). Significant differences in gestational age, oxygen supplementation (days), mechanical ventilation therapy (days), and sepsis between BPD and non-BPD groups were also observed (p < 0.05). There were no significant differences in the prevalence of family and personal history of atopy and/or allergic diseases, tobacco exposure, respiratory symptoms, respiratory syncytial virus bronchiolitis, exercise induced dyspnea, treatment with ß-2 bronchodilators and inhaled corticosteroids among the groups (p > 0.05). CONCLUSIONS: The respiratory function in preschool children born with ELBW is characterized by an increase in impedance and resistance of small airways. No statistically significant differences were found between ELBW children with BPD and without BPD. With regards to the smallest gestational age, the longer duration of O2 therapy during hospitalization, and sepsis significantly resulted in a worse respiratory function.

Use of vasoactive/vasodilating drugs for systemic sclerosis (SSc)-related digital ulcers (DUs) in expert tertiary centres: results from the analysis of the observational real-life DeSScipher study.

INTRODUCTION: DeSScipher is the first European multicentre study on management of systemic sclerosis (SSc), and its observational trial 1 (OT1) evaluated the efficacy of different drugs for digital ulcer (DU) prevention and healing. The aim of this study was to assess current use of vasoactive/vasodilating agents for SSc-related DU in the expert centres by analysing the baseline data of the DeSScipher OT1. METHOD: Baseline characteristics of patients enrolled in the OT1 and data regarding DU were analysed. RESULTS: The most commonly used drugs, in both patients with and without DU, were calcium channel blockers (CCBs) (71.6%), followed by intravenous iloprost (20.8%), endothelin receptor antagonists (ERAs) (20.4%) and phosphodiesterase 5 (PDE-5) inhibitors (16.5%). Of patients, 32.6% with DU and 12.8% without DU received two drugs (p < 0.001), while 11.5% with DU and 1.9% without DU were treated with a combination of three or more agents (p < 0.001). Sixty-five percent of the patients with recurrent DU were treated with bosentan and/or sildenafil. However, 64 out of 277 patients with current DU (23.1%) and 101 (23.6%) patients with recurrent DU were on CCBs alone. CONCLUSIONS: Our study shows that CCBs are still the most commonly used agents for DU management in SSc. The proportion of patients on combination therapy was low, even in patients with recurrent DU: almost one out of four patients with current and recurrent DU was on CCBs alone. Prospective analysis is planned to investigate the efficacy of different drugs/drug combinations on DU healing and prevention. Key Points • The analysis of DeSScipher, the first European multicentre study on management of SSc, has shown that the most commonly used vasoactive/vasodilating drugs for DU were CCBs, followed by intravenous Iloprost, ERAs and PDE-5 inhibitors. • More than half of the patients with recurrent DU received bosentan and/or sildenafil. • However, the proportion of patients on combination therapy of more than one vasoactive/vasodilating drug was low and almost one out of four patients with current and recurrent DU was on CCBs alone.

Classification, categorization and essential items for digital ulcer evaluation in systemic sclerosis: a DeSScipher/European Scleroderma Trials and Research group (EUSTAR) survey.

BACKGROUND: A consensus on digital ulcer (DU) definition in systemic sclerosis (SSc) has been recently reached (Suliman et al., J Scleroderma Relat Disord 2:115-20, 2017), while for their evaluation, classification and categorisation, it is still missing. The aims of this study were to identify a set of essential items for digital ulcer (DU) evaluation, to assess if the existing DU classification was useful and feasible in clinical practice and to investigate if the new categorisation was preferred to the simple distinction of DU in recurrent and not recurrent, in patients with systemic sclerosis (SSc). METHODS: DeSScipher is the largest European multicentre study on SSc. It consists of five observational trials (OTs), and one of them, OT1, is focused on DU management. The DeSScipher OT1 items on DU that reached ≥ 60% of completion rate were administered to EUSTAR (European Scleroderma Trials and Research group) centres via online survey. Questions about feasibility and usefulness of the existing DU classification (DU due to digital pitting scars, to loss of tissue, derived from calcinosis and gangrene) and newly proposed categorisation (episodic, recurrent and chronic) were also asked. RESULTS: A total of 84/148 (56.8%) EUSTAR centres completed the questionnaire. DeSScipher items scored by ≥ 70% of the participants as essential and feasible for DU evaluation were the number of DU defined as a loss of tissue (level of agreement 92%), recurrent DU (84%) and number of new DU (74%). For 65% of the centres, the proposed classification of DU was considered useful and feasible in clinical practice. Moreover, 80% of the centres preferred the categorisation of DU in episodic, recurrent and chronic to simple distinction in recurrent/not recurrent DU. CONCLUSIONS: For clinical practice, EUSTAR centres identified only three essential items for DU evaluation and considered the proposed classification and categorisation as useful and feasible. The set of items needs to be validated while further implementation of DU classification and categorisation is warranted. TRIAL REGISTRATION: Observational trial on DU (OT1) is one of the five trials of the DeSScipher project (ClinicalTrials.gov; OT1 Identifier: NCT01836263 , posted on April 19, 2013).

There is a need for new systemic sclerosis subset criteria. A content analytic approach.

OBJECTIVES: Systemic sclerosis (SSc) is heterogenous. The objectives of this study were to evaluate the purpose, strengths and limitations of existing SSc subset criteria, and identify ideas among experts about subsets. METHODS: We conducted semi-structured interviews with randomly sampled international SSc experts. The interview transcripts underwent an iterative process with text deconstructed to single thought units until a saturated conceptual framework with coding was achieved and respondent occurrence tabulated. Serial cross-referential analyses of clusters were developed. RESULTS: Thirty experts from 13 countries were included; 67% were male, 63% were from Europe and 37% from North America; median experience of 22.5 years, with a median of 55 new SSc patients annually. Three thematic clusters regarding subsetting were identified: research and communication; management; and prognosis (prediction of internal organ involvement, survival). The strength of the limited/diffuse system was its ease of use, however 10% stated this system had marginal value. Shortcomings of the diffuse/limited classification were the risk of misclassification, predictions/generalizations did not always hold true, and that the elbow or knee threshold was arbitrary. Eighty-seven percent use more than 2 subsets including: SSc sine scleroderma, overlap conditions, antibody-determined subsets, speed of progression, and age of onset (juvenile, elderly). CONCLUSIONS: We have synthesized an international view of the construct of SSc subsets in the modern era. We found a number of factors underlying the construct of SSc subsets. Considerations for the next phase include rate of change and hierarchal clustering (e.g. limited/diffuse, then by antibodies).

Use of optical coherence tomography for the diagnosis of preclinical lesions of circumscribed palmar hypokeratosis.

Circumscribed hypokeratosis of palms and soles is a rare dermatosis, usually affecting women. Diagnosis is mainly based on the clinical characteristics, including the clinical appearance and anatomical site of the skin lesions and on the demographic features of the affected patients, usually middle-aged to elderly women. Skin biopsy may be performed to confirm clinical diagnosis. Optical coherence tomography (OCT) is a technique that has been undergone substantial development in dermatology in recent years, and its use in clinical practice has been growing progressively. Several dermatological conditions have been studied with this tool, but to our knowledge, it has not been used to investigate this form of hypokeratosis. We report a case of circumscribed palmar hypokeratosis for which diagnosis was confirmed by OCT, which was performed as the patient was reluctant to undergo skin biopsy because of its invasiveness. We highlight the potential use of OCT in obtaining a virtual skin biopsy to confirm clinical diagnosis and identify preclinical skin lesions amenable to early treatment.

VITAMIN D AND BRONCHIAL INFLAMMATION IN ASTHMATIC CHILDREN.

The role of the vitamin D in calcium homeostasis and bone metabolism is well known. In recent years it has been recognized that in addition to the traditional functions, vitamin D modulates a variety of processes such as host defense, inflammation and immunity. Epidemiological data indicate that low levels of vitamin D in serum are associated with impaired lung function and increased incidence of inflammatory diseases, infectious diseases and cancer. The authors studied the correlation among vitamin D levels, allergic inflammation, lung function and control of asthma and found a significant decrease of FeNO values (p= 0.0018) in children with vitamin D levels>30 ng/ml. These findings confirm that vitamin D plays a major role in bronchial inflammation.

ß2-AGONISTS IN CHILDHOOD ASTHMA.

ß2-agonists reduce airflow limitation by improving airway diameter as a consequence of a direct action on airway smooth muscle. ß;2-agonists can be broadly classified according to their duration of action: short-acting ß2-agonists (SABAs), including albuterol, terbutaline and fenoterol, have pharmacodynamics half–lives between 2 and 6 h and long-acting ß2-agonists (LABAs), including salmeterol and formoterol, require twice daily treatment. SABAs are often used “as needed” for asthma exacerbations and before exercise in the presence of exercise-induced bronchospasm. LABAs provide longer symptom control, which is a particularly useful feature for preventing night-time symptoms. There are two main LABAs, salmeterol and formoterol. This review focused on the recent data published on this topic.

A role for caveolin-1 in desmoglein binding and desmosome dynamics.

Desmoglein-2 (Dsg2) is a desmosomal cadherin that is aberrantly expressed in human skin carcinomas. In addition to its well-known role in mediating intercellular desmosomal adhesion, Dsg2 regulates mitogenic signaling that may promote cancer development and progression. However, the mechanisms by which Dsg2 activates these signaling pathways and the relative contribution of its signaling and adhesion functions in tumor progression are poorly understood. In this study we show that Dsg2 associates with caveolin-1 (Cav-1), the major protein of specialized membrane microdomains called caveolae, which functions in both membrane protein turnover and intracellular signaling. Sequence analysis revealed that Dsg2 contains a putative Cav-1-binding motif. A permeable competing peptide resembling the Cav-1 scaffolding domain bound to Dsg2, disrupted normal Dsg2 staining and interfered with the integrity of epithelial sheets in vitro. Additionally, we observed that Dsg2 is proteolytically processed; resulting in a 95-kDa ectodomain shed product and a 65-kDa membrane-spanning fragment, the latter of which localizes to lipid rafts along with full-length Dsg2. Disruption of lipid rafts shifted Dsg2 to the non-raft fractions, leading to the accumulation of these proteins. Interestingly, Dsg2 proteolytic products are elevated in vivo in skin tumors from transgenic mice overexpressing Dsg2. Collectively, these data are consistent with the possibility that accumulation of truncated Dsg2 protein interferes with desmosome assembly and/or maintenance to disrupt cell-cell adhesion. Furthermore, the association of Dsg2 with Cav-1 may provide a mechanism for regulating mitogenic signaling and modulating the cell-surface presentation of an important adhesion molecule, both of which could contribute to malignant transformation and tumor progression.

Validity of the bath ankylosing spondylitis disease activity index for the evaluation of disease activity in axial psoriatic arthritis.

OBJECTIVE: To assess the validity of the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) for the evaluation and definition of disease activity of axial psoriatic arthritis (PsA). METHODS: Fifty-four peripheral PsA, 46 axial PsA, and 103 primary ankylosing spondylitis (AS) patients were assessed. Patients were classified as having axial PsA if they had grade 2 or higher unilateral sacroiliitis in the presence of spinal symptoms. The 3 groups of patients were evaluated using several measurements for AS. Assessments of acceptability, data quality, internal consistency, construct validity, and responsiveness of the BASDAI were undertaken. Disease activity of the disease was assessed in peripheral PsA and axial PsA patients using the BASDAI, and compared with those with AS. RESULTS: For peripheral PsA patients, the Cronbach's alpha for the BASDAI was 0.783, for axial PSA patients it was 0.647, and for AS patients it was 0.786. The analysis of convergent validity showed that in peripheral PsA and axial PsA patients, the BASDAI was significantly correlated with other subjective disease activity parameters. For responsiveness, no association was found between changes in the BASDAI and changes in disease activity either in peripheral PsA or in axial PsA. BASDAI scores were similar in axial PsA and AS. Axial PsA patients with a BASDAI score >4 cm showed significant differences with peripheral PsA in terms of disease activity and were very similar to patients with AS. CONCLUSION: The BASDAI performed similarly in evaluating disease activity in both axial and peripheral PsA. The BASDAI does not seem to be a good index for evaluating disease activity in axial PsA.

Junctional adhesion molecule-A is abnormally expressed in diffuse cutaneous systemic sclerosis skin and mediates myeloid cell adhesion.

OBJECTIVE: To investigate the role of junctional adhesion molecule-A (JAM-A) in the pathogenesis of systemic sclerosis (SSc). METHODS: Biopsy specimens from proximal and distal arm skin and serum were obtained from patients with SSc and normal volunteers. To determine the expression of JAM-A on SSc dermal fibroblasts and in SSc skin, cell surface ELISAs and immunohistology were performed. An ELISA was designed to determine the amount of soluble JAM-A (sJAM-A) in serum. Myeloid U937 cell-SSc dermal fibroblast and skin adhesion assays were performed to determine the role of JAM-A in myeloid cell adhesion. RESULTS: The stratum granulosum and dermal endothelial cells (ECs) from distal arm SSc skin exhibited significantly decreased expression of JAM-A in comparison with normal volunteers. However, sJAM-A was increased in the serum of patients with SSc compared with normal volunteers. Conversely, JAM-A was increased on the surface of SSc compared with normal dermal fibroblasts. JAM-A accounted for a significant portion of U937 binding to SSc dermal fibroblasts. In addition, JAM-A contributed to U937 adhesion to both distal and proximal SSc skin. CONCLUSIONS: JAM-A expression is dysregulated in SSc skin. Decreased expression of JAM-A on SSc ECs may result in a reduced response to proangiogenic basic fibroblast growth factor. Increased JAM-A expression on SSc fibroblasts may serve to retain myeloid cells, which in turn secrete angiogenic factors.

Anti-apoptotic effect of transforming growth factor-beta1 on human articular chondrocytes: role of protein phosphatase 2A.

OBJECTIVE: To study whether transforming growth factor-beta1 (TGF-beta1) is able to protect human chondrocytes from apoptosis and to analyze the role of phosphatases in the possible anti-apoptotic effect of TGF-beta1. METHODS: Cartilage was obtained from patients with osteoarthritis (OA) who were undergoing joint replacement; normal cartilage was obtained from cadavers who had no history of joint disease. Chondrocytes stimulated with tumor necrosis factor-alpha (TNF-alpha) plus Ro 31-8220 (a specific inhibitor of mitogen-activated kinase phosphatase-1 - MKP-1) were employed as an in vitro model of apoptosis. Apoptosis was assessed by flow cytometry and a cell death immunoassay. Protein phosphatase 2A (PP2A) activity was estimated by measuring the absorbance of a molybdate:malachite green:phosphate reaction complex. MKP-1, bcl-2 and bax expressions were quantified by western blot. RESULTS: In OA cells, TGF-beta1 significantly reduced the percentage of hypo-diploid chondrocytes, as well as the percentage of internucleosomal DNA breakage. However, in normal chondrocytes, TGF-beta1 did not reduce apoptosis, as assessed by both the percentage of hypo-diploid chondrocytes and internucleosomal DNA breakage. MKP-1 expression did not show significant modulation in OA or normal chondrocytes. However, PP2A activity was differentially modulated in normal and OA chondrocytes. In OA chondrocytes, PP2A activity was not altered by TGF-beta1 stimulation; however in normal chondrocytes PP2A activity was significantly activated by TGF-beta1. The preincubation of normal chondrocytes with TGF-beta1 plus the PP2A inhibitor protein, IPP2A, reduced internucleosomal DNA breakage when compared with TGF-beta1 stimulation alone. The bcl-2/bax protein ratio was significantly higher in TGF-beta1 plus IPP2A preincubated normal chondrocytes than in cells stimulated with TGF-beta1 alone. CONCLUSION: By manipulating the degree of PP2A activity, these results show the major role that PP2A plays in the outcome of TGF-beta1 signal transduction. These data suggest that PP2A could be a pivotal regulator of anti-apoptotic TGF-beta1-induced effects.

Differential effects of tumor necrosis factor-alpha and interleukin-1beta on cell death in human articular chondrocytes.

OBJECTIVE: The death of chondrocytes by apoptosis is characteristic of degenerative joint diseases, such as osteoarthritis (OA). Tumor necrosis factor-alpha (TNF-alpha) and interleukin-1beta (IL-1beta) have been shown to play an important role in the development of OA. In this study we analyzed the effects of TNF-alpha and IL-1beta on cell death in normal human chondrocytes. METHODS: Normal human chondrocytes were isolated from knee cartilage obtained at autopsy from 30 adult cadaveric donors. The cells were stimulated with TNF-alpha (10 ng/ml) or IL-1beta (5 ng/ml) in the presence or absence of Ro 31-8220 (Ro: a structurally related analog of bisindolylmaleimide that inhibits mitogen-activated protein kinase phosphatase 1 [MKP-1]) (Ro; 10 microM), an MKP-1 inhibitor, which induces apoptosis in chondrocytes. Apoptosis was evaluated by flow cytometry (propidium iodide) and nuclear morphology was evaluated with 4',6'-dianidino-2-phenylindole dihydrochloride. The expressions of caspase-8, -7 and -3 and Bcl-2 were analyzed by Western blot and the activation of caspase-3 and -8 was measured by flow cytometry. Prostaglandin E2 (PGE2) was evaluated by enzyme-linked immunosorbent assay. RESULTS: At 24 h the percentage of apoptotic (hypodiploid) nuclei induced by TNF-alpha+Ro was higher than the level induced by Ro alone. The combination of IL-1beta (5 ng/ml) with Ro did not show a synergistic effect. A morphological analysis demonstrated that treatment with TNF-alpha+Ro resulted in a large number of cells with condensed nuclei and DNA fragmentation. Western blot studies indicated that IL-1beta+Ro did not induce the time-dependent activation of caspase-8, -7 and -3 as seen with TNF-alpha+Ro. As quantified by flow cytometry, TNF-alpha+Ro induced a higher level of caspase-3 and -8 activation than that seen with IL-1beta+Ro. Pre-incubation for 2h with caspase inhibitors for caspase-3, -7, -8 and pan-caspase significantly decreased the hypodiploid DNA peak induced by treatment with TNF-alpha+Ro at 24 h. Indomethacin increased the cell death induced by IL-1beta+Ro; however, apoptosis induced by TNF-alpha+Ro was not modified by indomethacin. CONCLUSIONS: These results confirm that TNF-alpha and IL-1beta regulate apoptosis differently in this human chondrocyte model and that the differing effects of these cytokines are PGE2-independent. Indomethacin potentiates the effect of IL-1 on cell death and this may explain the reported effect of indomethacin on the progression of joint destruction.

Cytokines, tumor necrosis factor-alpha and interleukin-1beta, differentially regulate apoptosis in osteoarthritis cultured human chondrocytes.

OBJECTIVE: This study addresses the effects of tumor necrosis factor-alpha (TNF-alpha) and interleukin-1beta (IL-1beta) on cell death in human chondrocytes. METHODS: Osteoarthritis (OA) human chondrocytes stimulated with Actinomycin-D (ActD) were used as a cellular apoptotic model. Caspase family mRNA expression and protein synthesis were analyzed by the ribonuclease protection assay and Western-blot, respectively. Cell viability and apoptosis were evaluated using the 3-[4,5-dimethylthiazol-2yl] 2,5-diphenyl tetrazolium bromide (MTT) assay and flow cytometry, respectively. Prostaglandin E2 (PGE2) and nitric oxide (NO) were evaluated by enzyme-linked immunosorbent assay (ELISA) and the Griess method, respectively. RESULTS: TNF-alpha and IL-1beta differentially affected the pattern of caspase mRNA expression by human chondrocytes. TNF-alpha induced a gradual increase in caspase-1 and -8 mRNA levels that was not seen with IL-1beta. The time sequence of caspase-3 and -7 inductions by TNF-alpha differs from that induced by IL-1beta. Cell viability was not modified by TNF-alpha or IL-1beta in cultured chondrocytes. Then, we employed ActD as a model to facilitate cell death. Treatment with TNF-alpha and ActD (TNF-alpha/ActD) increased cell death induced by ActD (23%). Treatment with IL-1beta and ActD (IL-1beta/ActD) did not modulate ActD-induced cell death. Similarly, IL-1beta/ActD did not induce an increase in the activation of caspase-3 and -7 and poly (ADP-ribose) polymerase (PARP) cleavage observed by the incubation with TNF-alpha/ActD. These different effects were not due to bcl-2 or mcl-1 levels. Inhibition of PGE2 synthesis by indomethacin increased the cell death induced by IL-1beta/Act-D (59%). An inhibitor of caspase-8 significantly reduced only the TNF-alpha/ActD-induced cell death (58%). CONCLUSION: TNF-alpha and IL-1beta differentially regulate the apoptotic pathway in human chondrocytes. This difference is dependent on PGE2 and caspase-8 levels.

Cytotoxic molecule mRNA expression in chronically rejected human kidney allografts.

The pathogenesis of immunological and nonimmunological components that cause chronic kidney allograft nephropathy (CAN), is not yet completely understood. To explore the possible contribution of alloreactive cytotoxic T cells, we analyzed the transcription of cytotoxic molecules such as granzyme B and perforin using semiquantitative RT-PCR on surgically removed grafts obtained from two groups: group 1 (n = 10) were cases of CAN; group 2 (n = 3) had no CAN. Among group 1 kidneys, granzyme-B was expressed in 7 of 10, whereas perforin was detectable in 9 of 10 cases; their detection was not related to the presence of superimposed signs of acute graft lesions. Cytotoxic molecules were never found in group 2 kidneys. These results show that explanted chronically rejected grafts display cytotoxic molecule transcripts in addition to Th2 type cytokines, such as IL-10, IL-3, and IL-6, suggesting that both cellular and humoral alloreactive mechanisms may play important roles in CAN pathogenesis.

Phosphatase-1 and -2A inhibition modulates apoptosis in human osteoarthritis chondrocytes independently of nitric oxide production.

OBJECTIVE: To characterise the role of phosphatase-1 and -2A (PP1/2A) in the modulation of apoptosis in human osteoarthritis (OA) chondrocytes. METHODS: Human OA chondrocytes were isolated from cartilage obtained from the femoral heads of patients undergoing joint replacement surgery. Cell viability was evaluated by MTT assay. Apoptosis was quantified by ELISA, which measures DNA fragmentation. Nitric oxide (NO) production was evaluated by the Greiss method, and inducible nitric oxide synthase (iNOS) protein synthesis was studied by western blotting. RESULTS: Inhibition of PP1/2A by the specific inhibitor okadaic acid (OKA) dose and time dependently caused a reduction of cell viability (OKA at 50 nmol/l: a reduction to 60% and 43% at 48 and 72 hours, respectively). Genomic DNA from chondrocytes treated with OKA at 50 and 100 nmol/l for 48 hours displayed increased internucleosomal DNA fragmentation by 11 and 13 fields, respectively. Light microscopy and DAPI studies showed that OKA induced DNA condensation and fragmentation, typical of death by apoptosis. The caspase inhibitors Z-VAD-FMK and Z-DEVD-FMK increased cell viability, reduced by OKA at 50 nmol/l to 87% and 73%, respectively. OKA did not increase iNOS protein synthesis or NO production. CONCLUSION: PP1/2A modulate apoptosis in human OA chondrocytes; this is independent of NO production but dependent on caspases.

Effect of nitric oxide on mitochondrial respiratory activity of human articular chondrocytes.

OBJECTIVE: To investigate the effect of nitric oxide (NO) on mitochondrial activity and its relation with the apoptosis of human articular chondrocytes. MATERIALS AND METHODS: Mitochondrial function was evaluated by analysing respiratory chain enzyme complexes, citrate synthase (CS) activities, and mitochondrial membrane potential (Delta psi m). The activities of the mitochondrial respiratory chain (MRC) complexes (complex I: NADH CoQ(1) reductase, complex II: succinate dehydrogenase, complex III: ubiquinol cytochrome c reductase, complex IV: cytochrome c oxidase) and CS were measured in human articular chondrocytes isolated from normal cartilage. The Delta psi m was measured by 5,5',6,6'-tetracholoro-1,1',3,3'-tetraethylbenzimidazole carbocyanide iodide (JC-1) using flow cytometry. Apoptosis was analysed by flow cytometry. The mRNA expression of caspases was analysed by ribonuclease protection analysis and the detection of protein synthesis by western blotting. Sodium nitroprusside (SNP) was used as an NO compound donor. RESULTS: SNP at concentrations higher than 0.5 mmol/l for 24 hours induced cellular changes characteristic of apoptosis. SNP elicited mRNA expression of caspase-3 and caspase-7 and down regulated bcl-2 synthesis in a dose and time dependent manner. Furthermore, 0.5 mM SNP induced depolarisation of the mitochondrial membrane at 5, 12, and 24 hours. Analysis of the MRC showed that at 5 hours, 0.5 mM SNP reduced the activity of complex IV by 33%. The individual inhibition of mitochondrial complex IV with azide modified the Delta psi m and induced apoptosis. CONCLUSIONS: This study suggests that the effect of NO on chondrocyte survival is mediated by its effect on complex IV of the MRC.

Prevalence of HLA-B27 and subtypes of HLA-B27 associated with ankylosing spondylitis in Galicia, Spain.

OBJECTIVE: To assess the prevalence of HLA-B27 and its subtypes in both the normal population and in patients with Ankylosing Spondylitis (AS) in Galicia, Northwest Spain. METHODS: The prevalence of HLA-B27 in the normal population was determined by checking the number of HLA-B27 positive samples in 308 subjects from different areas of Galicia who had donated organs over a period of 4 years. A total of 106 patients with the diagnosis of AS, according to the modified New York clinical criteria for definitive ankylosing spondylitis, were collected from three very representative areas of Galicia. HLA-B27 was determined by PCR using the primers E91s and E136as, while 11 subtypes of HLA-B27 were analyzed using a commercial kit. RESULTS: The prevalence of HLA-B27 in organ donors was 9.34%. HLA-B27 was present in 94.3% of patients with AS. Subtypes B*2701, B*2709 and B*2710 were not found. The subtypes found in the normal population were; B*2705 (79.5%), B*2702 (18%) and B*2708 (2.5%). The subtypes associated with AS were B*2705 (88%) and B*2702 (12%). CONCLUSION: The prevalence of HLA-B27 in Galicia was 9.34%, which is higher than previously published in Spain. The frequency of the subtypes associated with AS was similar to that reported for other Spanish regions.