In situ analysis of interleukin-23- and interleukin-12-positive cells in the spine of patients with ankylosing spondylitis.

OBJECTIVE: The interleukin-12 (IL-12) family of cytokines has been suggested to play a critical role in inflammatory autoimmune diseases, and recent studies analyzing peripheral blood and synovial fluid from patients with spondyloarthritides suggest that IL-23 might be a proinflammatory factor in these disorders. This study was undertaken to investigate the presence and source of IL-23 in the spines of patients with ankylosing spondylitis (AS). METHODS: The frequency of IL-23-positive and IL-12-positive cells within the subchondral bone marrow and within fibrous tissue replacing normal bone marrow in facet joints of patients with AS was analyzed by immunohistochemistry. The origin of IL-23-positive cells was determined by double staining of CD163+ macrophages, CD68+ macrophages, CD1a+ dendritic cells, tryptase-positive mast cells, myeloperoxidase-positive cells, CD20+ B cells, and CD3+ T cells. Findings in 28 facet joints from 22 AS patients were compared with those in 20 facet joints from 13 patients with osteoarthritis (OA) and 10 normal control specimens. RESULTS: The frequency of IL-23-positive cells in subchondral bone marrow from the joints of AS patients (mean ± SD 42.50 ± 32.81/high-power field [hpf]) was significantly increased compared to that in subchondral bone marrow from OA patients (OA 15.63 ± 29.90/hpf) (P = 0.0017) or controls (19.36 ± 16.8/hpf) (P = 0.03). Myeloperoxidase-positive cells and, to a lesser extent, macrophages and dendritic cells were found to be the origin of IL-23 in the bone marrow. In AS and OA patients, the frequency of IL-23-positive cells was significantly higher than that of IL-12-positive cells (P < 0.001 in both patient groups). Within fibrous tissue from AS and OA facet joints, IL-23 was predominantly produced by CD163+ macrophages (mean ± SD 0.64 ± 0.59/hpf and 4.36 ± 3.4/hpf, respectively) and CD68+ macrophages (2.3 ± 0.65/hpf and 6.54 ± 4.1/hpf, respectively). CONCLUSION: IL-23 is expressed in the subchondral bone marrow and in fibrous tissue replacing bone marrow in facet joints of patients with AS. It might have a role in inflammatory processes and in chronic changes in AS joints, which makes it an interesting potential therapeutic target in this disease.

Repeat full-thickness resection device use for recurrent duodenal adenoma: A case report.

BACKGROUND: Endoscopic full-thickness resection of adenomas or subepithelial tumors is a novel and promising endoscopic technique. There have been several recent studies of full-thickness resection device (FTRD) use in the colon, but data regarding its use and efficacy in the duodenum are still limited. CASE SUMMARY: A 64-year-old female underwent resection of a recurrent adenoma of 7 mm in size in the duodenum after FTRD use for an adenoma eight months prior. The biopsies revealed a low-grade adenoma. The adenoma was removed using the gastroduodenal FTRD, and the pathology results revealed clear margins. Except for minor bleeding that was treated by argon plasma coagulation, no further complications occurred. CONCLUSION: Repeat use of the FTRD appears to be a safe and efficacious approach for the treatment of recurrent duodenal lesions. Further prospective studies are needed to investigate the long-term safety and utility of repeat FTRD use after Endoscopic full-thickness resection.

ADAPT-treated pericardium for aortic valve reconstruction in congenital heart disease: histological analysis of a series of human explants.

OBJECTIVES: Different types of patch materials are used for aortic valve repair in children with congenital aortic valve disease to avoid early valve replacement. CardioCel© (Admedus, Toowong, QLD, Australia) consists of bovine pericardium treated with the ADAPT method (Admedus' proprietary tissue engineering process). METHODS: Our goal was to describe tissue reactions in 12 explanted aortic valve leaflet specimens (augmented or replaced with CardioCel patch material) (11 explanted surgically, 1 autopsy). Explantation was performed during reoperation after aortic valve repair, necessitated by aortic valve stenosis in 5, aortic valve insufficiency in 2, combined aortic valve lesions in 3 patients and endocarditis in 1 patient. One patient died of sudden left heart failure 28 months after aortic valve repair. At the last documented follow-up of this patient at 22 months, he showed mild aortic valve stenosis and insufficiency. Implantation time (time between implantation and explantation) of CardioCel patches was a median of 25 (range 11-47) months. Explants were examined using a uniform protocol with methylmethacrylate and/or paraffin embedding after fixation in formalin. Besides standard histological staining, von Kossa (for identification of calcifications) and immunohistochemical stains were applied with antibodies specific for muscular, inflammatory and connective tissue component antigens. Findings regarding the extent of appositional growth on top of the patch consisting of fibroblasts and extracellular matrix components, calcification, and inflammation were rated using a 4-grade scale (G0 no/G1 few/G2 moderate/G3 massive). RESULTS: Superficial endothelialization was demonstrated in all patients by immunohistochemical analysis. Nine specimens showed mild inflammatory cell infiltration (G1) (G2: n = 3). Significant appositional growth on top of the patch due to addition of fibroblasts and extracellular matrix components, was seen in all specimens (G1: n = 1; G2: n = 7; G3: n = 4). Ten of 12 samples with implant times of 23 months or longer revealed calcifications (G1: n = 6; G2: n = 3; G3: n = 1). Two specimens with the shortest implant times (11 and 20 months) showed no calcifications (G0). Thrombus apposition with granulocyte infiltration was demonstrated in the specimen of the patient with endocarditis. CONCLUSIONS: In our cohort, all CardioCel patches used for aortic valve repair in patients with congenital heart disease demonstrated appositional growth of fibroblasts and extracellular matrix components, and calcification after an implant time of at least 23 months.

Effects of ethanol on cytokine production after surgery in a murine model of gram-negative pneumonia.

BACKGROUND: Both alcohol abuse and surgery have been shown to impair immune function. The frequency of postoperative infectious complications is 2- to 5-fold increased in long-term alcoholic patients, leading to prolonged hospital stay. Following surgery, an increase in interleukin (IL)-6 has been shown to be associated with increased tissue injury and interleukin 1-(IL-10) is known to represent an anti-inflammatory signal. The purpose of this study was to test the hypothesis that several days of excess alcohol consumption results in more pronounced immunosuppression. We assume that alcoholic animals show increased levels of IL-10 in response to infection and increased IL-6 due to a more pronounced lung pathology. METHODS: Thirty-two female Balb/c mice were pretreated with ethanol (EtOH) at a dose of (3.8 mg/g body weight) or saline (NaCl) for 8 days. At day 8 of the experiment all mice underwent a median laparotomy. Two days postsurgery mice were either applicated 10(4) CFU Klebsiella pneumoniae or received sham-infection with saline. A total number of 4 groups (EtOH/K. pneumoniae; NaCl/K. pneumoniae; EtOH/Sham-infection, NaCl/Sham-infection) was investigated and a clinical score evaluated. Twenty-four hours later mice were killed; lung, spleen, and liver were excised for protein isolation and histological assessment. IL-6 and IL-10 levels were detected by ELISA. RESULTS: Alcohol-exposed mice exhibited a worsened clinical appearance. The histological assessment demonstrated a distinct deterioration of the pulmonary structure in alcohol-treated animals. In the lung, IL-6 and IL-10 was significantly increased in alcohol-exposed infected mice compared to saline-treated infected mice. The clinical score correlated significantly with IL-6 (r = 0.71; p < 0.01) and IL-10 levels (r = 0.64; p < 0.01) in the lung. CONCLUSIONS: Ethanol treatment in this surgical model led to a more severe pulmonary infection with K. pneumoniae which was associated with more tissue destruction and increased levels of IL-6 and IL-10 and a worsened clinical score.

Hypocalcemia and osteopathy in mice with kidney-specific megalin gene defect.

Megalin is an endocytic receptor highly expressed in the proximal tubules of the kidney. Recently, we demonstrated that this receptor is essential for the renal uptake and conversion of 25-OH vitamin D3 to 1,25-(OH)2 vitamin D3, a central step in vitamin D and bone metabolism. Unfortunately, the perinatal lethality of the conventional megalin knockout mouse model precluded the detailed analysis of the significance of megalin for calcium homeostasis and bone turnover in vivo. Here, we have generated a new mouse model with conditional inactivation of the megalin gene in the kidney by using Cre recombinase. Animals with a renal-specific receptor gene defect were viable and fertile. However, lack of receptor expression in the kidney results in plasma vitamin D deficiency, in hypocalcemia and in severe bone disease, characterized by a decrease in bone mineral content, an increase in osteoid surfaces, and a lack of mineralizing activity. These features are consistent with osteomalacia (softening of the bones) as a consequence of hypovitaminosis D and demonstrate the crucial importance of the megalin pathway for systemic calcium homeostasis and bone metabolism.

Cartilage in facet joints of patients with ankylosing spondylitis (AS) shows signs of cartilage degeneration rather than chondrocyte hypertrophy: implications for joint remodeling in AS.

INTRODUCTION: In ankylosing spondylitis (AS), joint remodeling leading to joint ankylosis involves cartilage fusion. Here, we analyzed whether chondrocyte hypertrophy is involved in cartilage fusion and subsequent joint remodeling in AS. METHODS: We assessed the expression of chondrocyte hypertrophy markers runt-related transcription factor 2 (Runx2), type X collagen (COL10), matrix metalloproteinase 13 (MMP13), osteocalcin and beta-catenin and the expression of positive bone morphogenic proteins (BMPs) and negative regulators (dickkopf-1 (DKK-1)), sclerostin, (wingless inhibitory factor 1 (wif-1)) of chondrocyte hypertrophy in the cartilage of facet joints from patients with AS or osteoarthritis (OA) and from autopsy controls (CO) by immunohistochemistry. Sex determining region Y (SRY)-box 9 (Sox9) and type II collagen (COL2) expression was assessed as indicators of chondrocyte integrity and function. RESULTS: The percentage of hypertrophic chondrocytes expressing Runx2, COL10, MMP13, osteocalcin or beta-catenin was significantly increased in OA but not in AS joints compared to CO joints. Frequencies of sclerostin-positive and DKK-1-positive chondrocytes were similar in AS and CO. In contrast, wif-1- but also BMP-2- and BMP-7-expressing and Sox9-expressing chondrocytes were drastically reduced in AS joints compared to CO as well as OA joints whereas the percentage of COL2-expressing chondrocytes was significantly higher in AS joints compared to CO joints. CONCLUSIONS: We found no evidence for chondrocyte hypertrophy within hyaline cartilage of AS joints even in the presence of reduced expression of the wnt inhibitor wif-1 suggesting that chondrocyte hypertrophy is not a predominant pathway involved in joint fusion and remodeling in AS. In contrast, the reduced expression of Sox9, BMP-2 and BMP-7 concomitantly with induced COL2 expression rather point to disturbed cartilage homeostasis promoting cartilage degeneration in AS.

Histomorphologic and histomorphometric characteristics of zygapophyseal joint remodeling in ankylosing spondylitis.

OBJECTIVE: To unravel the mechanisms that control bony ankylosis in ankylosing spondylitis (AS). METHODS: Histomorphologic and histomorphometric analyses were performed on zygapophyseal joints obtained from 18 patients with AS, 9 patients with osteoarthritis (OA), and 10 cadaver donors without a rheumatic disease (controls). The proteoglycan content of the cartilage was determined by Safranin O staining and the chondrocyte apoptosis according to caspase 3 expression. RESULTS: AS joints were categorized into 3 groups according to the morphology of the joint surfaces and joint space: group 1 were joints with an open joint space, group 2 were joints with cartilaginous fusion, and group 3 were joints with bony fusion of the joint surfaces. Progressive loss of the joint space from group 1 joints to group 3 joints suggests that this grouping corresponds to sequential stages of joint remodeling. Cartilage thickness and subchondral bone plate thickness declined from group 1 to group 3 (P < 0.01). Increased chondrocyte apoptosis rates were found in groups 1 and 2 (P < 0.05), while in group 3, a reduction in the proteoglycan content was found (P < 0.001). Bone marrow replacement and invasion of the subchondral bone plate by fibrous tissue was found predominantly in AS joints in group 2. CONCLUSION: Cartilage degeneration, indicated by cartilage thinning, enhanced chondrocyte apoptosis, and proteoglycan loss, and subchondral bone thinning, promoted by invasion of the subchondral bone plate by a fibrous tissue originating from the bone marrow, are hallmarks of joint remodeling in AS.

Clostridium septicum can cause distant myonecrosis in patients with ovarian cancer.

A case report of lethal distant myonecrosis with gas gangrene is presented. Blood cultures and tissue biopsies revealed Clostridium septicum. The 55-year-old female patient presented with recurrent ovarian cancer of transitional cell type, initially diagnosed as FIGO IIb in January 2011, with hepatic metastasis and invasion of the ceacal wall. She underwent several operations, including partial bowel and liver resection in September 2011. Second-line therapy with topotecan three weekly was started in October 2011 while the patient was still in the hospital. During this chemotherapy, the patient revealed symptoms of severe pain and erythema of the skin. Within hours she died of sceptic shock after a debridement. The diagnosis was gas gangrene due to Clostridium septicum. Because it is a rare and severe disease and the time slot in which therapeutic measures can be taken is narrow, we discuss clinical symptoms and therapeutic options.

Expression profiling confirms the role of endocytic receptor megalin in renal vitamin D3 metabolism.

BACKGROUND: The endocytic receptor megalin constitutes the major pathway for clearance of low-molecular weight plasma proteins from the glomerular filtrate into the renal proximal tubules. Furthermore, the receptor has been implicated in a number of other functions in the kidney including uptake and activation of 25-(OH) vitamin D3, calcium and sodium reabsorption as well as signal transduction. METHODS: We used genome-wide expression profiling by microarray technology to detect changes in the gene expression pattern in megalin knockout mouse kidneys and to uncover some of the renal pathways affected by megalin deficiency. RESULTS: Alterations were identified in several (patho)physiologic processes in megalin-deficient kidneys including the renal vitamin D metabolism, transforming growth factor (TGF)-beta1 signal transduction, lipid transport and heavy metal detoxification. Most importantly, changes were detected in the mRNA levels of 25-(OH) vitamin D-24-hydroxylase and 25-(OH) vitamin D-1alpha-hydroxylase as well as strong up-regulation of TGF-beta1 target genes. Both findings indicate plasma vitamin D deficiency and lack of vitamin D signaling in renal tissues. CONCLUSIONS: Expression profiling confirms a crucial role for megalin in renal vitamin D metabolism.

Kidney-specific inactivation of the megalin gene impairs trafficking of renal inorganic sodium phosphate cotransporter (NaPi-IIa).

Renal reabsorption of inorganic phosphate is mediated by the type IIa sodium phosphate cotransporter (NaPi-IIa) of the proximal tubule. Changes in renal phosphate handling are mainly attributable to altered NaPi-IIa brush border membrane (BBM) expression. Parathyroid hormone (PTH) induces inactivation of NaPi-IIa by endocytic membrane retrieval and degradation. The key elements triggering this process are not clear to date. Megalin serves as a receptor for the endocytosis of multiple ligands and is coexpressed with NaPi-IIa in the proximal tubule. Investigated was the role of megalin in the regulation of NaPi-IIa in steady state and during inactivation. Kidneys and tubular BBM fractions from mice with a renal-specific megalin gene defect and from controls were analyzed by light and electron microscopic histochemical techniques and Western blot test. Steady-state levels of NaPi-IIa in BBM were significantly enhanced, mRNA levels preserved, and phosphaturia reduced in the absence of megalin. Fluid-phase endocytosis was prevented and the apical endocytic apparatus markedly reduced. Systemic administration of PTH resulted in a defective retrieval and impaired degradation of NaPi-IIa. In vitro, the application of various stimuli of the PTH-induced signaling cascade had no effect either. Adequate steady-state expression of NaPi-IIa and the capacity of the proximal tubule cell to react on PTH-driven inactivation of NaPi-IIa by endocytosis and intracellular translocation require the presence of megalin.