Positron emission tomography with 18F-FDG in osteoarthritic knee

OBJECTIVES

To evaluate osteoarthritis (OA) of the knee using positron emission tomography (PET) with 2-(18)F-fluoro-2-deoxy-D-glucose ((18)F-FDG) as a tracer.

MATERIALS AND METHODS

Fifteen patients with medial-type knee OA and three healthy subjects were enrolled in the study. After clinical examination and conventional radiography, (18)F-FDG PET and magnetic resonance imaging (MRI) were performed. (18)F-FDG uptake was quantified as a standardized uptake value (SUV) and the localization of (18)F-FDG uptake was identified using fusion images created with MRI scans.

RESULTS

(18)F-FDG generally accumulated in periarticular lesions and was absent in the articular cartilage. SUVs of the whole knee were higher in OA than in controls, and those in the medial condyle were higher than in the lateral condyle in OA. Prominent (18)F-FDG uptake was found in the intercondylar notch in OA and extended along the posterior cruciate ligament (PCL) in some cases. Periosteophytic accumulation was found in one-half of cases with definite osteophytes. Accumulation was also found in subchondral lesions and bone marrow, which corresponded with bone edema diagnosed by MRI. No significant correlation was found between SUV and clinical manifestations.

CONCLUSIONS

(18)F-FDG uptake was upregulated in OA and generally accumulated in periarticular lesions. Increased uptake was found in the intercondylar notch extending along the PCL, periosteophytic lesions, and bone marrow. These results provide in vivo pathognomonic insights into OA.

Surgical resection of solitary adrenal metastasis from esophageal carcinoma following esophagectomy

The prognosis of esophageal carcinoma following esophagectomy is poor due to a high frequency of metastasis to periesophageal lymph nodes and distant organs. However, we experienced a case with good prognosis following resection of a solitary adrenal metastatic tumor. The patient was a 70-year-old man diagnosed with type 2 esophageal cancer (Lt-Ae, T2N1M0, Stage IIB) who was treated with esophagectomy. Eight months following surgery, solitary adrenal metastasis was detected by CT, and was resected. At 42 months follow-up he has had a good quality of life in the community without evidence of recurrence. To the best of our knowledge, only five cases with resected solitary adrenal metastases including our case, have been reported, and show a greater than 1-year survival. Consequently, we suggest that resection of solitary organ metastases is a good alternative, even following esophagectomy.

Effects of celecoxib on human chondrocytes--enhanced production of chemokines

OBJECTIVE

The purpose of this study was to examine the effects of a selective cyclooxigenase-2 (COX-2) inhibitor (celecoxib) comparing diclofenac.

METHODS

Using chondrocytes derived from cartilage of non-arthritic (NA) subjects or patients with osteoarthritis (OA) or rheumatoid arthritis (RA), we examined the effects of celecoxib on incorporation of 3H-thymidine and 35S-sulfate, apoptosis, and production of matrix metalloproteinase (MMP)-1, MMP-3, MMP-13, and regulated upon activation, normal T cell expressed and secreted (RANTES), macrophage inflammatory protein (MIP)-1a and nitric oxide (NO).

RESULTS

Celecoxib and diclofenac tended to reduce 3H-tymidine incorporation of chondrocytes. Celecoxib induced apoptosis in a dose-dependent manner, but to a lesser degree than diclofenac. Celecoxib inhibited proteoglycan synthesis (indicated by 35S-sulfate incorporation) in NA chondrocytes, but not in OA and RA chondrocytes. Celecoxib increased interleukin-1 (IL-1)-induced production of RANTES and MIP-1alpha by chondrocytes and decreased IL-1-induced NO production by chondrocytes, whereas it did not affect MMP production.

CONCLUSION

Celecoxib had both beneficial and adverse effects on chondrocytes. RA, OA and NA chondrocytes showed different responses. Interestingly, celecoxib enhanced the production of chemokines.

Expression of proteinase-activated receptors (PAR)-2 in articular chondrocytes is modulated by IL-1beta, TNF-alpha and TGF-beta

OBJECTIVE

To investigate the modulation of expression of proteinase-activated receptor-2 (PAR-2) in articular chondrocytes by inflammatory cytokines.

DESIGN

Articular synovium and cartilage tissues were collected from eight patients with osteoarthritis (OA), and three patients without arthropathy ("normal"). Chondrocytes were stimulated with interleukin (IL)-1beta, tumor necrosis factor (TNF)-alpha or transforming growth factor (TGF)-beta1. The expression of PAR-2 was detected using reverse transcriptase-polymerase chain reaction (PCR), Western blotting and immunofluorescence. Quantitative PCR was performed to assess the expression levels of PAR-2 messenger RNA (mRNA).

RESULTS

The expression of PAR-2 mRNA was demonstrated in both OA and normal chondrocytes as well as in synovial fibroblasts. However, the level of PAR-2 in OA chondrocytes was much higher than in normal chondrocytes. Long-term culture revealed that PAR-2 mRNA expression was maintained up to three passages in OA but not in normal chondrocytes. IL-1beta and TNF-alpha both upregulated PAR-2 expression in normal and OA chondrocytes. In contrast, TGF-beta1 significantly decreased expression of PAR-2 in OA chondrocytes but increased PAR-2 in normal chondrocytes.

CONCLUSIONS

Overexpression of PAR-2 in OA chondrocytes is upregulated by proinflammatory cytokines IL-1beta and TNF-alpha, and down-regulated by regulatory cytokine TGF-beta1. PAR-2 may be involved in the pathogenesis of OA.

Staphylococcal scalded skin syndrome I. Purification of exfoliatin and maternal transmission of neutralizing ability against exfoliatin

Exfoliatin, an exotoxin produced by phage group 2 staphylococci, was separated and was analyzed. The toxin was separated in a single peak by Sephadex G-100 gel filtration and subsequent DEAE Sephadex chromatography. By acrylamide gel disc electrophoresis this single peak was found to contain 2 components both of which posessed exfoliative activity and the same antigenic properties. Their molecular weight, however, differed; the major component had a molecular weight of 30,000 and the minor component had 27,000. The toxin was stable when heated at 60 degrees C for 40 minutes, and labile at 100 degrees C for 20 minutes. The toxin was immunogenic to mice and produced antibody which could be transmitted to neonatal mice to neutralize exfoliative activity of the toxin. Innoculation of the bacteria caused the production of antibodies against both exfoliatin and alpha-hemolysin in mice. The antibodies were also transmitted to neonatal mice to neutralize the exfoliative activity of exfoliatin.

The role of subchondral bone resorption pits in osteoarthritis: MMP production by cells derived from bone marrow

OBJECTIVE

The vascular invasion of bone marrow tissue into the subchondral plate is often observed in articular cartilage and we named it the subchondral bone absorption pit; however, its implication in the pathogenesis of osteoarthritis (OA) has been poorly understood. The purpose of this study was to evaluate its characteristics and roles in osteoarthritic conditions.

METHODS

Articular cartilage specimens from 11 patients with medial type knee OA and 7 non-arthritic cadavers were analyzed with HE staining. OA sections were stained with safranin-O, TRAP (tartrate resistant acid phosphatase) and immunostained with anti-MMP-1, MMP-3, MMP-13, vitronectin receptor (VNR)-alpha chain, vimentin and bone morphogenic protein (BMP) 2/4 antibodies.

RESULTS

Subchondral bone resorption pits were classified according to the extent of invasion: pits with bone marrow tissue were located within uncalcified cartilage below the tidemark in grade I and invaded beyond the tidemark in grade II, while no invasion was seen in grade 0. Grade II pits were dominant in OA compared to non-arthritic joints, especially medial condyles. Proteoglycan detected with safranin-O staining was lost around the tip of grade II pits and the density of pits was related to the modified Mankin Score. Cells in pits expressed vimentin, MMP-1, MMP-3 and MMP-13. Some polynuclear cells co-expressed VNR-alpha chain and MMP-13, whereas pits showed reparative features expressing BMP.

CONCLUSION

These results suggest that subchondral bone resorption pits contribute to cartilage degradation by expressing matrix metalloproteinases in OA.

Implication of interleukin 18 in production of matrix metalloproteinases in articular chondrocytes in arthritis: direct effect on chondrocytes may not be pivotal

OBJECTIVE

To clarify the effect of interleukin (IL) 18 on cartilage degeneration by studying the profile of IL18 receptor (IL18R) on chondrocytes and the direct effect of IL18 on production of matrix metalloproteinases (MMPs), aggrecanases, and tissue inhibitors of metalloproteinases (TIMPs) in articular chondrocytes.

METHODS

Monolayer cultured human articular chondrocytes were isolated from non-arthritic subjects and patients with rheumatoid arthritis or osteoarthritis. Gene expression of IL18, IL18Ralpha, IL18Rbeta, MMPs, and aggrecanases was detected by RT-PCR. Protein levels of IL18Ralpha were analysed by flow cytometry. Protein levels of IL18, MMPs, and TIMPs were measured by ELISA. Aggrecanase-2 mRNA expression was quantitatively analysed by real time RT-PCR. Protein levels of signalling molecules were assayed by western blotting.

RESULTS

IL18 mRNA was constitutively expressed in chondrocytes, and was enhanced by IL1beta stimulation. Flow cytometric analysis showed that IL1beta, tumour necrosis factor alpha, and IL18 up regulated IL18Ralpha expression levels. The level of IL18Rbeta mRNA was much lower than that of IL18Ralpha, and was slightly up regulated by IL1beta. In chondrocytes responding to IL18, IL18 (1-100 ng/ml) slightly increased the production of MMP-1, MMP-3, and MMP-13, which was blocked by NF-kappaB inhibitor and p38 mitogen activated protein kinase inhibitor. IL18 up regulated mRNA expression of aggrecanase-2, but not aggrecanase-1. IL18 also slightly stimulated TIMP-1 production?through extracellular signal regulated kinase activation.

CONCLUSION

IL18 induces production of MMPs from chondrocytes in inflammatory arthritis. Although the direct effect of IL18 on chondrocytes may not be pivotal for the induction of cartilage degeneration, IL18 seems to play some part in the degradation of articular cartilage in arthritis.

Plasminogen activator inhibitor-1 is elevated, but not essential, in the development of bleomycin-induced murine scleroderma

Accumulative data have demonstrated that plasminogen activator inhibitor-1 (PAI-1) plays an important role in the extracellular matrix metabolism; however, the involvement of PAI-1 in scleroderma has not been fully elucidated. In this study, we investigated the role of PAI-1 in bleomycin-induced murine scleroderma. 100 microg of bleomycin was injected subcutaneously to the back skin of C3H/HeJ mice on alternate day for 4 weeks. Histopathological findings revealed that PAI-1 was positive in macrophage-like cells and fibroblastic cells in the dermis, in parallel with the induction of dermal sclerosis. PAI-1 mRNA expression in the whole skin was up-regulated at 1 and 4 weeks. The production of active PAI-1 protein in the lesional skin was significantly increased 3 and 4 weeks after bleomycin treatment. Next, we examined whether dermal sclerosis is induced by bleomycin in PAI-1-deficient (PAI-1-/-) mice. 10 microg of bleomycin was subcutaneously injected to PAI-1-/- and wild type (WT) mice 5 days per week for 4 weeks. Histological examination revealed that dermal sclerosis was similarly induced even in PAI-1-/- as well as WT mice. Dermal thickness and collagen contents in the skin were significantly increased by bleomycin injection in both PAI-1-/- and WT mice, and the rate of increase was similar. These data suggest that PAI-1 plays an important role, possibly via TGF-beta pathway activation. However, the fact that PAI-1 deficiency did not ameliorate skin sclerosis suggest that PAI-1 is not the essential factor in the development of bleomycin-induced scleroderma, and more complex biochemical effects other than PA/plasmin system are greatly suspected.

In vivo transfection of a cis element 'decoy' against signal transducers and activators of transcription 6 (STAT6)-binding site ameliorates IgE-mediated late-phase reaction in an atopic dermatitis mouse model

Signal transducers and activators of transcription 6 (STAT6) play a crucial role in the transactivation of IL-4 and IL-13, which might be involved in the pathogenesis of atopic dermatitis (AD). We herein reported that the IgE-mediated late-phase reaction significantly decreased in STAT6-deficient (STAT6(-/-)) mice in AD model mice induced by intravenous injection of monoclonal anti-dinitrophenyl (DNP)-IgE antibody and subsequent skin testing with dinitrofluorobenzene. We therefore hypothesized that synthetic double-stranded DNA with a high affinity for STAT6 could be introduced in vivo as decoy cis elements to bind the transcriptional factor and block the gene activation contributing to the onset and progression of AD, thus providing effective therapy for AD. Treatment by the transfection of STAT6 decoy oligodeoxynucleotides (ODNs), but not scramble decoy ODN after sensitization by anti-DNP-IgE antibody, had a significant inhibitory effect on not only STAT6 binding to nuclei but also on the late-phase response. A histological analysis revealed that both edema and the infiltration of neutrophils and eosinophils significantly decreased in STAT6 decoy ODN-transfected mice. To examine the mechanism of the in vivo effect of STAT6 decoy ODN, we employed an in vitro mast cells culture system. After IgE receptor engagement, mast cells transfected by STAT6 decoy ODN exhibited normal histamine release, but their cytokine release (TNF-alpha, IL-6) markedly decreased. We herein report the first successful in vivo transfer of STAT6 decoy ODN to reduce the late-phase reaction, thereby providing a new therapeutic strategy for AD.

In vivo transfection of a cis element 'decoy' against signal transducers and activators of the transcription 6 (STAT6) binding site ameliorates the response of contact hypersensitivity

We herein demonstrate that STAT6 plays an important role in the induction of not only acute contact hypersensitivity (CHS), but also chronic CHS in a mouse model using STAT6-deficient (STAT6(-/-)) mice. We, therefore, determine whether synthetic double-stranded DNA with a high affinity for STAT6 can be introduced in vivo as a decoy cis element to bind the transcriptional factor and block the induction of not only acute CHS but also chronic CHS. Treatment by the transfection of STAT6 decoy oligodeoxynucleotides (ODN), after the induction of 2,4,6-trinitrochlorobenzene or other haptens had a significant inhibitory effect on the induction of both acute CHS and chronic CHS. We thus examined the mechanism of the in vivo effect of the transfection of STAT6 decoy ODN in both acute and chronic CHS. In the histological analysis, the infiltration of eosinophils and degranulated mast cells, and the production of IL-4, IL-6 and eotaxin, but not IFN-gamma in the extracts from challenged skin significantly decreased by the transfection of STAT6 decoy ODN. We herein report the first successful in vivo transfer of STAT6 decoy ODN to inhibit acute and chronic CHS, thus providing a new therapeutic strategy not only for the treatment of CHS but also for atopic dermatitis.

Chemokines differentially induce matrix metalloproteinase-3 and prostaglandin E2 in human articular chondrocytes

OBJECTIVE

To explore prostaglandin (PG) E2 production by human articular chondrocytes induced by different chemokines.

METHODS

Human chondrocytes were enzymatically isolated from the articular cartilage of patients with rheumatoid arthritis (RA), osteoarthritis (OA) or traumatic fracture (N) who underwent total joint replacement. They were cultured in vitro as monolayers and then exposed to MCP-1, RANTES or SDF-1 for 24 h. Levels of PGE2 and MMP-3 in the culture supernatant were then immunoassayed.

RESULTS

PGE2 production was enhanced up to 2.7-fold in a subset of samples. Responses to different chemokines were heterogeneous even within the same disease groups. As previously reported, chemokines induced MMP-3 secretion by chondrocytes, but there was no significant correlation between levels of PGE2 and MMP-3.

CONCLUSION

We here document the presence of "responders" among OA, RA and normal chondrocytes that produce enhanced levels of PGE2 upon stimulation by chemokines. The relationship between chemokines and prostaglandins could differentially influence the pathogenic network responsible for cartilage degradation in arthropathy.

Interleukin (IL) 18 stimulates osteoclast formation through synovial T cells in rheumatoid arthritis: comparison with IL1 beta and tumour necrosis factor alpha

OBJECTIVE

To determine whether IL18 has any indirect effects on osteoclastogenesis mediated by T cells in RA synovium, and compare its effects with those of IL1 beta and TNF alpha.

METHODS

Resting T cells were isolated from peripheral blood of healthy donors, and stimulated with 2 microg/ml phytohaemagglutinin (PHA) and 0.5 ng/ml IL2 for 24 hours. Synovial T cells were isolated from RA synovial tissue. The levels of soluble receptor activator of the NF-kappa B ligand (RANKL), osteoprotegerin (OPG), IFN gamma, M-CSF, and GM-CSF were determined by ELISA. Membrane bound RANKL expression was analysed by flow cytometry. Commercially available human osteoclast precursors were cocultured with T cells to induce osteoclast formation, which was determined with tartrate resistant acid phosphatase staining and pit formation assay.

RESULTS

In PHA prestimulated T cells or RA synovial T cells, IL18, IL1 beta, or TNFalpha increased soluble RANKL production and membrane bound RANKL expression in a dose dependent manner. IL18, IL1 beta, and TNF alpha did not induce M-CSF, GM-CSF, IFN gamma, or OPG production in PHA prestimulated T cells or RA synovial T cells. IL18 increased the number of osteoclasts and bone resorption area on dentine slices in the coculture of human osteoclast precursors with PHA prestimulated T cells or RA synovial T cells; its ability was equivalent to that of IL1 beta, but less potent than that of TNF alpha. In the coculture system, OPG completely blocked osteoclast induction by IL18 or IL1 beta, and greatly inhibited induction by TNF alpha.

CONCLUSION

IL18, IL1 beta, or TNF alpha can indirectly stimulate osteoclast formation through up regulation of RANKL production from T cells in RA synovitis; IL18 is as effective as IL1 beta, but less potent than TNF alpha.

Staphylococcal scalded skin syndrome. II. Serum level of anti exfoliatin and anti alpha-toxin in patients with staphylococcal scalded skin syndrome or bullous impetigo

In order to study the differences between staphylococcal scalded skin syndrome (SSSS) and bullous impetigo, the anti exfoliatin level was assessed in the sera from both groups of patients, and no significant difference in the level was found. However a significant difference was noted in the anti alpha-toxin levels in sera from both group of patients; that of SSSS patients was much lower than that of impetigo patients and of children in a control group. Five out of 6 patients with SSSS showed an unchaged level of anti alpha-toxin at the second examination, while an increased anti exfoliatin level was noted in 4 out of 6 SSSS patients.

Telomerized presenescent osteoblasts prevent bone mass loss in vivo

Previously, we showed that human osteoblasts expressing the human telomerase reverse transcriptase (hTERT) gene exhibited specific survival advantages--the result of breaching the replicative senescence barrier and maintaining the phenotypic and functional properties of primary osteoblasts in vitro over the total replicative capacity of primary osteoblasts. We postulated that rejuvenated osteoblasts may have a potential to correct bone loss or osteopenia in age-related osteoporotic diseases. In the present study, we studied whether telomerized presenescent osteoblasts prevent bone mass loss in vivo. After obtaining the informed consent from a patient with osteoarthritis who underwent the arthroplastic knee surgery, osteoblastic cells were isolated from donor bone sample. We transfected the gene encoding hTERT into human osteoblastic cells. Human bone fragments from a donor were incubated with human hTERT-transfected presenescent (in vitro aged) osteoblasts or mock-transfected presenescent osteoblasts in culture medium containing Matrigel. We subcutaneously implanted human bone fragments with telomerized presenescent osteoblasts or primary presenescent osteoblasts as three-dimensional Matrigel xenografts in severe combined immunodeficiency (SCID) mice (each group: six mice) and analyzed the grafts at 6 weeks after implantation. We also determined whether telomerized osteoblasts affect the bone-forming capacity in vivo, using a well-established mouse transplantation model in which ceramic hydroxyapatite/tricalcium phosphate particles are used as carrier vehicle. Telomerized presenescent osteoblasts were rejuvenated, and maintained the functional properties of young osteoblasts in vitro. Bone mineral content (BMC) and bone mineral density (BMD) were measured by ash weight and dual-energy X-ray absorptiometry, respectively. Whereas BMC and BMD of human bone fragments, which were inoculated with aged osteoblasts in SCID mice, decreased with time, telomerized presenescent osteoblasts maintained the BMC and BMD of human bone fragments, indicating that telomerized and rejuvenated osteoblasts may be functional to prevent bone mass loss in vivo. In xenogenic transplants, telomerized osteoblasts generated more bone tissue with lamellar bone structure and cellular components, than did control osteoblasts. These findings suggest that telomerized/rejuvenated presenescent osteoblasts may be used in the development of tissue engineering or cell-based therapy for bone regeneration and repair.

Involvement of UV-irradiation in pemphigus foliaceus

Ultraviolet (UV) light has been implicated in inducing acantholysis in the uninvolved skin of pemphigus patients. This report presents the case of a 55-year-old man with pemphigus foliaceus in whom skin lesions were induced and exacerbated by UV-irradiation.

Effects of glucosamine hydrochloride on the production of prostaglandin E2, nitric oxide and metalloproteases by chondrocytes and synoviocytes in osteoarthritis

OBJECTIVES

To determine the response of glucosamine hydrochloride on chondrocytes and synoviocytes in terms of prostaglandin E2 (PGE2), nitric oxide (NO) and matrix metalloproteases (MMPs).

METHODS

Chondrocytes and synoviocytes were prepared from joint specimens of patients who underwent total knee arthroplasty for osteoarthritis (OA). Chondrocytes from patients with femoral neck fracture were served as a normal control. Culture cells were stimulated by 5 ng/ml of IL-1beta and treated with various concentration of glucosamine hydrochloride (from 1 microg/ml to 500 microg/ml). PGE2, NO, MMP-1, MMP-3, and MMP-13 levels were evaluated in the culture supernatant. Further, the expression of COX-2 mRNA was studied by semiquantitative PCR.

RESULTS

With IL-1beta stimulation, the levels of these mediators increased dramatically, except for NO from synoviocytes. After stimulation, levels of these mediators in OA chondrocytes were higher than synoviocytes and normal chondrocytes, and the level of MMP-3 was higher than those of MMP-1 and MMP-13. Glucosamine hydrochloride at a concentration of 100 microg/ml suppressed PGE2 production, and partly suppressed NO production. It also suppressed the production of MMPs from normal chondrocytes and synoviocytes but not from OA chondrocytes.

CONCLUSION

Glucosamine modulates the metabolism of chondrocytes and synoviocytes and its mode of action differs between cells and conditions.

Characterisation of cartilage intermediate layer protein (CILP)-induced arthropathy in mice

OBJECTIVES

To characterise cartilage intermediate layer protein (CILP)-induced arthropathy in mice.

METHODS

The first and second halves of the nucleotide triphosphate pyrophosphohydrolase (NTPPHase) non-homologous region of human CILP were prepared as recombinant proteins (C1 and C2, respectively), including three overlapping fragments of C2 (C2F1, C2F2, and C2F3). C57BL/6 mice were immunised with these proteins to induce arthritis. In addition, a separate group of mice were immunised repeatedly with the mixture of C1 and C2 to see the effect of chronic immunisation. Arthritis developed in the mice, and cellular and humoral immune responses against CILP were analysed.

RESULTS

Immunisation with C2 and with the mixture C2F1/C2F2/C2F3 caused the severest arthritis to develop in mice. Immunisation with one of C1, C2F1, C2F2, or C2F3 caused milder arthritis, even though each of the fragments carried T cell epitopes. Immunisation either with C1 or C2 alone evoked cellular and humoral immune responses to both the C1 and C2 proteins. Further, the repeated immunisation with the C1/C2 mixture caused tendon calcification and bone irregularity, together with decreased NTPPH activity.

CONCLUSIONS

The results show that multiple T cell epitopes are needed for the development of CILP-induced arthritis, and present the characteristic new model of mild arthropathy accompanied by extra-articular calcifications. An immune response to putative murine CILP/NTPPH may be involved in the ectopic calcifications in the arthritic mice.