CCR2-dependent intraepithelial lymphocytes mediate inflammatory gut pathology during Toxoplasma gondii infection

Mice of the C57BL/6 strain develop acute ileal inflammation after infection with the protozoan parasite Toxoplasma gondii. This pathology resembles many key features of human Crohn's disease, including a Th1 cytokine profile with high levels of interferon gamma (IFN-gamma), interleukin 12 (IL)-12, and tumor necrosis factor alpha (TNF)-alpha, presence of pathogenic CD4(+) T cells, and infiltration of gut flora into inflammed tissue. Using CCR2(-/-) mice, we identify a role for this chemokine receptor in the pathogenesis of inflammatory pathology during T. gondii infection. Lack of chemokine (C-C motif) receptor 2 (CCR2) was associated with low levels of CD103(+) T lymphocytes in the intraepithelial compartment, Peyer's patch, and lamina propria relative to wild-type animals. Adoptive transfer of wild-type, but not IFN-gamma(-/-), intraepithelial T lymphocytes converted CCR2 knockout mice from a resistant to susceptible phenotype with respect to parasite-triggered inflammatory gut pathology. These results for the first time show a role for intraepithelial T lymphocytes in pathogenesis of ileitis triggered by a microbial pathogen.

Regulation of desaturase expression in HL60 cells

The expression of delta 5 desaturase (D5D), delta 6 desaturase (D6D) and delta 9 desaturase (D9D) was determined by RT-PCR in the human promyelocytic cell line HL60. During 72 h of culture with 10% FBS, D5D and D6D were upregulated 5 to 6-fold, whereas D9D approximately doubled. The addition of fatty acids (FAs) to the culture medium suppressed upregulation of all desaturases. N-3 and n-6 FA appeared to be more effective than n-9 or saturated FA. When FAs were added after 72 h, further upregulation during the next 24 h was suppressed for nearly all desaturases and FAs tested, except for D5D when oleic acid (OA) or stearic acid (SA) was added. In cells cultured with restricted amounts of FBS, desaturase expression increased with decreasing concentrations of FBS. Cellular FA content decreased by 60% in the neutral lipid fraction, whereas that of the phospholipid fraction decreased by 10% during 72 h of culture. The largest decrease occurred in the sum of n-3 and n-6 FA of the neutral lipid fraction, which was reduced by 83%, whereas the content of these FAs in the phospholipid fraction decreased by 32%. The results indicate that when the supply of FA to HL60 cells is limited, the intracellular content of n-3 and n-6 FA decreases and this leads to upregulation of the desaturases, particularly D5D and D6D. Since HL60 cells resemble human leukocytes, the results suggest that desaturase expression in leukocytes may be exploited as a biomarker for FA status.

[Retrospective 5-year analysis of MR-guided biopsies in a low-field MR system]

PURPOSE

The purpose of this study was to evaluate the safety and clinical value of MR-guided biopsies in an open 0.2 T low-field system.

MATERIALS AND METHODS

A total of 322 patients with suspicious lesions of different body regions were biopsied in a low-field MRI system (0.2 T, Concerto, Siemens). The procedures were guided using T 1-weighted Flash sequences (TR/TE = 100/9; 70 degrees). The lesions were repeatedly biopsied using the coaxial technique with a 15-gauge (diameter 2 mm) puncture needle. Complications and biopsy findings were analyzed retrospectively.

RESULTS

In all cases the biopsy procedures were successfully performed with MR guidance. In 298 patients diagnosis was able to be confirmed on the basis of the probes. The clinical follow-up showed that in 24 patients the lesions were missed by MR-guided biopsy. From this a sensitivity of 86%, a specificity of 87% and an accuracy of 93% were calculated. In two patients major complications were observed (morbidity rate 0.6 %).

CONCLUSION

MR-guided biopsy can be performed safely and precisely in a low-field MR system and are a supplement to US or CT-guided biopsies.

[Interventional emergency embolization for severe pelvic ring fractures with arterial bleeding. Integration into the early clinical treatment algorithm]

OBJECTIVE

Presentation of our own experiences and results of an early clinical algorithm for treatment integrating emergency embolization (TAE) in cases of unstable pelvic ring fractures with arterial bleeding.

METHOD

Consecutive patient series from April 2002 to December 2006 at a level 1 trauma center. The data of the online shock room documentation (Traumawatch) of patients with a pelvic fracture and arterial bleeding detected on multislice computed tomography (MSCT) were examined for the following parameters: demographic data, injury mechanism, fracture classification according to Tile/AO and severity of the pelvic injury assessed with the Abbreviated Injury Score (AIS), accompanying injuries with elevation of the cumulative injury severity according to the Injury Severity Score (ISS), physiological admission parameters (circulatory parameters and initial Hb value) as well as transfusion requirement during treatment in the shock room, time until embolization, duration of embolization, and source of bleeding.

RESULTS

Of a total of 162 patients, arterial bleeding was detected in 21 patients by contrast medium extravasation on MSCT, 12 of whom were men and 9 women with an average age of 45 (14-80) years. The mechanism of injury was high energy trauma in all cases. In 33% it involved type B pelvic fractures and in 67% type C fractures with an average AIS pelvis of 4.4 points (3-5) and a total severity of injury with the ISS of 37 points (21-66). Upon admission 47.6% presented hemodynamic instability with an average Hb value of 7.8 g/dl (3.2-12.4) and an average transfusion requirement of 6 red blood cell units (4-13). The time until the TAE was started was on average 62 min (25-115) with a duration period of the TAE of 25 min (15-67). Branches of the internal iliac artery were identified as the sole source of bleeding. The success rate of TAE amounted to over 90%.

CONCLUSION

Interventional TAE represents an effective as well as a fast procedure for hemostasis of arterial bleeding detected on MSCT in patients with pelvic fractures. If an experienced radiologist on 24-h stand-by is assured and the infrastructure is efficient, this can be performed shortly after hospital admission and therefore should be integrated into the early clinical treatment protocol.

Functional expression of the chemokine receptor CCR7 on fibroblast-like synoviocytes

OBJECTIVES

We have characterized the expression and the function of the chemokine receptor CCR7 on fibroblast-like synoviocytes (FLS) of patients with RA and OA and on dermal fibroblasts.

METHODS

FLS were obtained after enzymatic digestion of synovial tissue (ST) of patients with RA and OA undergoing knee replacement surgery and taken into culture for chemokine receptor analysis by RT-PCR, flow cytometry and functional tests. Immunofluorescence for CCR7, fibroblast and T-cell markers was performed on ST of RA and OA patients. To study the response of FLS to CCR7 ligands and other chemokines, migration assays were performed in modified Boyden chambers. After stimulation of FLS with CCR7 ligands, the secretion of VEGF was evaluated by ELISA and Luminex.

RESULTS

CCR7 is expressed on FLS of patients with RA and OA, but not on dermal fibroblasts. FLS migrated in response to the CCR7 ligands, CCL19 and CCL21. Stimulation of FLS with CCL19 resulted in a significantly increased secretion of VEGF of RA- and OA-FLS.

CONCLUSION

Apart from the migration of FLS in response to CCL19 and CCL21, it was shown that activation of the CCR7 receptor on FLS results in an enhanced VEGF secretion. A considerable expression of CCR7 ligands in proximity to perivascular infiltrates has previously been described in inflamed synovial tissue of RA patients. Stimulation of FLS via CCR7 could thereby contribute to angiogenesis in the synovial tissue.

MR-Thermometrie bei 1,5 Tesla zur thermischen Ablation mittels laserinduzierter Thermotherapie

PURPOSE

Evaluation of thermometry with fast MR sequences for laser-induced interstitial laser therapy (LITT) and verification of the thermometric results with a fiber-optic thermometer.

METHOD AND MATERIALS

In vitro experiments were conducted using an agarose gel mixture and pig liver lobes. MR-guided LITT was performed using a laser power between 3 and 15 watts. Thermometry was performed using longitudinal relaxation time T1 and proton resonance frequency shift (PRF) methods under acquisition of amplitude and phase shift images. PRF was measured with a fast spoiled GRE sequence. Four different sequences were used for T1 thermometry: gradient echo (GE), TrueFISP (TRUFI), Saturation Recovery Turbo-FLASH (SRTF) and Inversion Recovery Turbo-FLASH (IRTF) sequences. The temperature was controlled using a fiber-optic Luxtron device and correlated with the MR temperature. The range of applied and monitored temperatures exceeded 80 degrees Celsius.

RESULTS

The temperature dependence showed a good linear relationship up to 60 degrees Celsius. Calibration experiments for the T1 method delivered coefficients of determination from 0.977 to 0.997 for agarose and from 0.958 to 0.995 for the pig liver samples. The IRTF sequence had the highest temperature sensitivity (agarose 0.99, liver 1.19). During LITT the TRUE-FISP sequence exhibited a strong nonlinear relationship. R (2) of this sequence was 0.809 in the agarose experiments. The average temperature errors when heated up to 80 degrees Celsius were 3.86-11.38 degrees Celsius for Agarose gel and 5.7-12.16 degrees Celsius for the liver tissue. SRTF and IRTF sequences exhibited the most linear relationship with temperature but were more dependent on tissue differences.

CONCLUSION

The accuracy of the temperature measurement is sufficient for controlling the coagulation area of the LITT. PRF is the method of choice since it shows the best linear correlation with fiber-optic temperature. If only T1 sequences are concerned, the FLASH sequence is preferred. It is the most robust, though not the most accurate, T1 sequence.

Evaluation of Soluble CD30 as an Immunologic Marker in Heart Transplant Recipients

CD30 is an immunologic molecule that belongs to the TNF-R superfamily. CD30 serves as a T-cell signal transducing molecule that is expressed by a subset of activated T lymphocytes, CD45RO+ memory T cells. Augmentation of soluble CD30 during kidney transplant rejection has been reported. Our study sought to determine whether the level of sCD30 prior to heart transplant could categorize patients into high versus low immunologic risk for a poor outcome. A significant correlation was observed between high levels of soluble CD30 and a reduced incidence of infection. None of the 35 patients with high pretransplant levels of sCD30 level (>90 U/mL) developed infections posttransplantation. However, 9 of 65 patients who had low levels of sCD30 (<90 U/mL) developed infections posttransplantation (P < .02). No remarkable differences were noted among the other clinical parameters. The results also showed that the high-definition flow-bead (HDB) assay detected both weak and strong class I and class II HLA antibodies, some of which (weak class II HLA Abs) were undetectable by the anti-human globulin cytotoxicity method. In addition, more antibody specificities were detected by HDB. In conclusion, we have observed that high levels of sCD30 prior to heart transplant may be associated with greater immunologic ability and therefore produce a protective effect on the development of infection post heart transplant. We have also shown that the HDB assay is superior to the visual cytotoxicity method to detect HLA antibodies, especially those to class II HLA antigens.

Exanthema and acute anuric renal failure

A 15-year-old girl with a history of Kawasaki disease was admitted to our nephrological department due to acute renal failure. Despite antibiotic therapy because of fever and the symptoms of a pharyngitis in the last few days, the girl showed persisting fever and developed arthralgias, an exanthema and a rising serum creatinine as well as anuria. A wide variety of differential diagnoses has to be thought of because of the history of the Kawasaki disease (symptoms like fever, pharyngitis, exanthema and arthralgia), i.e. hemolytic-uremic syndrome, vasculitis, ascending infection, postinfection glomerulonephritis. In consideration of etiologically unclear "rapidly progressive renal failure" with anuria and thrombocytopenia an immediate renal biopsy was done and revealed a severe drug induced acute interstitial nephritis. Due to this diagnosis we treated the patient with corticosteroids. Within 4 weeks serum creatinine declined to 1.8 mg/dl but did not normalize.

Increase in renal vascular resistance after intake of cyclosporin A and tacrolimus and reversal by nitroglycerin spray: a study in patients with stable renal allograft function

PURPOSE

Acute effects of drug administration on renal arterial resistance index (RI) are still discussed controversially. In our study we investigated the immediate effects of cyclosporin A (CyA) and tacrolimus (FK-506) on renal arterial resistance indices in patients with stable graft function after renal transplantation. Additionally we studied the effects of nitroglycerin spray on resistance indices.

METHODS

RI was measured by color Doppler sonography at baseline, at 1 and 2 hours after intake of medication and 30 minutes after administration of nitroglycerin spray which followed the 2-hour measurement. 34 renal transplant recipients were examined. 16 patients received CyA, 18 patients received FK-506. Whole blood levels of calcineurin inhibitors were taken at each time point. Arterial blood pressure and heart rate were measured to assess possible systemic hemodynamic effects.

RESULTS

Mean RI values increased significantly in both groups 1 hour after calcineurin inhibitor intake and remained still significantly elevated after 2 hours. There was no significant increase of mean arterial blood pressure nor was there any correlation between whole blood levels of calcineurin inhibitors and mean RI. 30 minutes after administration of nitroglycerin spray, mean RI values decreased significantly to a level even below baseline. Mean arterial blood pressure also decreased after administration of nitroglycerin.

CONCLUSION

Renal RI values are markedly influenced by a recent intake of calcineurin inhibitors and vasoactive substances such as nitrates. This demonstrates the necessity of keeping standardized conditions when using RI as a tool in followup investigations after renal transplantation.

[Contrast-enhanced diagnostics in orthopaedics]

The diagnostic competence of the orthopaedist not only allows him to perform adequate therapy concepts, but also to meet the current structural challenges, both social and health related. In addition to clinical diagnosis, machine-aided diagnosis is becoming more important due to technical advances. In this context, contrast-enhanced examination has a special place, as it has an important diagnostic advantage in difficult or unclear cases. Current improvements in the areas of phlebography, myelography, arthrography and angiography are reviewed. Indications, risks and complications as well as the technical procedure are critically discussed.

Percutaneous vertebroplasty in the therapy of osteoporotic vertebral compression fractures: a critical review

Percutaneous vertebroplasty has become an efficient technique for the treatment of painful vertebral fractures. Osteoporotic vertebral compression fractures are characterized by severe back pain and immobilization causing other complications like thrombosis or pneumonia. Vertebral cement augmentation provides increased strength of the vertebral body and an obvious pain relief. Between 1989 and 2004, 30 studies and a total of 2,086 treated patients have been published in literature. A review of these studies has been performed. The number and age of the patients, number of treated vertebrae, pre- and postoperative outcome of pain and complications of the different studies were assessed and analyzed. Percutaneous vertebroplasty is an efficient technique with low complication rates and a significant reduction in pain. It rapidly improves the mobility and quality of life of patients with vertebral compression fractures. With an increasing number of treated patients, experience with this interventional technique has become excellent. But still there are no randomized controlled trials available, showing that percutaneous vertebroplasty has a significantly better outcome than other treatment options, especially after a long-term follow-up.

Transient chemokine receptor blockade does not prevent, but may accelerate type 1 diabetes in prediabetic NOD mice

The influx of autoreactive lymphocytes into the site of an autoimmune inflammation is mediated by certain chemokines. Autoimmune insulitis in type 1 diabetes is viewed as the result of destructive Th-1-cells and their corresponding antigen-presenting cells infiltrating the pancreatic islets. Blocking the chemokine receptors that mediate a Th-1-reaction has been shown to reduce autoimmunity in other experimental autoimmune disorders. We used the NOD mouse model to investigate the potency of anti-CCR2 and anti-CCR5 antibodies to inhibit the influx of Th-1-cells into the pancreatic islets, thus preventing diabetes onset. Eleven-week-old female NOD mice were treated with 500 microg of a monoclonal anti-CCR5 or anti-CCR2 or an isotype control antibody every third day over two weeks. We did not observe any preventive effect in either treatment group, but accelerated diabetes onset in the anti-CCR5 treated group. The number of autoantigen-specific Th-1-cells detected in the two treated groups was not reduced, but increased in the anti-CCR5 group. Redundancy within the chemokine system may account for this lack of prevention, or the intervention may have come too late in the disease process. Furthermore, blocking Th-1 chemokine receptors in the late autoimmune process may also inhibit regulatory T-cells, thus accelerating rather than preventing the disease.