Th-1 polarization is regulated by dendritic-cell comparison of MHC class I and class II antigens

In the control of T-helper type I (Th-1) polarization, dendritic cells (DCs) must interpret a complex array of stimuli, many of which are poorly understood. Here we demonstrate that Th-1 polarization is heavily influenced by DC-autonomous phenomena triggered by the loading of DCs with antigenically matched major histocompatibility complex (MHC) class I and class II determinants, that is, class I and II peptide epitopes exhibiting significant amino acid sequence overlap (such as would be physiologically present during infectious processes requiring Th-1 immunity for clearance). Data were derived from 13 independent antigenic models including whole-cell systems, single-protein systems, and 3 different pairs of overlapping class I and II binding epitopes. Once loaded with matched class I and II antigens, these "Th-1 DCs" exhibited differential cytokine secretion and surface marker expression, a distinct transcriptional signature, and acquired the ability to enhance generation of CD8(+) T lymphocytes. Mechanistically, tRNA-synthetases were implicated as components of a putative sensor complex involved in the comparison of class I and II epitopes. These data provide rigorous conceptual explanations for the process of Th-1 polarization and the antigenic specificity of cognate T-cell help, enhance the understanding of Th-1 responses, and should contribute to the formulation of more effective vaccination strategies.

PTPN22 deficiency cooperates with the CD45 E613R allele to break tolerance on a non-autoimmune background

Pep and CD45 are tyrosine phosphatases whose targets include the Src-family kinases, critical mediators of Ag receptor signaling. A polymorphism in PTPN22, the gene that encodes the human Pep orthologue Lyp, confers susceptibility to multiple human autoimmune diseases in the context of complex genetic backgrounds. However, the functional significance of the R620W risk allele is not clear. We report that misexpression of wild-type or R620W Pep/Lyp in Jurkat cells, in the context of its binding partner Csk, unmasks the risk allele as a hypomorph. It has been shown previously that although Pep-deficient mice on the B6 background have hyperresponsive memory T cells, autoimmunity does not develop. Mice containing a point mutation in the CD45 juxtamembrane wedge domain (E613R) develop a B cell-driven, lupus-like disease on the mixed 129/B6 background, but not on the B6 background. We studied the ability of Pep deficiency to act as a genetic modifier of the CD45 E613R mutation on the nonautoimmune B6 background to understand how complex susceptibility loci might interact in autoimmunity. In this study we report that double mutant mice develop a lupus-like disease as well as lymphadenopathy, polyclonal lymphocyte activation, and accelerated memory T cell formation. Following Ag receptor stimulation, peripheral B cells in the double mutant mice phenocopy hyperresponsive CD45 E613R B cells, whereas peripheral T cells respond like Pep(-/-) T cells. These studies suggest that Pep(-/-) T cells in the context of a susceptible microenvironment can drive hyperresponsive CD45 E613R B cells to break tolerance.

PTPN22 deficiency cooperates with the CD45 E613R wedge allele to break tolerance on a non-autoimmune background (49.18)

Pep and CD45 are tyrosine phosphatases whose targets include the Src-family kinases, critical mediators of antigen receptor signaling. A polymorphism in PTPN22, the gene that encodes the human Pep ortholog Lyp, confers susceptibility to multiple human autoimmune diseases. However, the significance of the R620W risk allele is not clear. We report that misexpression of wild type or R620W Lyp/Pep in Jurkat cells, in the context of their binding partner Csk, unmasks the risk allele as a hypomorph.

Although Pep deficient mice on the B6 background have hyper-responsive memory T cells, they fail to develop autoimmune disease. Mice containing a point mutation in CD45 (E613R) develop a B cell-driven lupus-like disease on the mixed 129/B6, but not on the B6 background. To model in mice how human susceptibility loci such as PTPN22 cooperate to provoke autoimmune disease, we studied the ability of Pep deficiency to act as a genetic modifier of the CD45 E613R mutation on the non-autoimmune B6 background.

Double mutant mice develop a lupus-like disease as well as a lymphoproliferative syndrome. Following antigen receptor stimulation, peripheral B cells in the double mutant mice phenocopy hyper-responsive CD45 E613R B cells, whereas peripheral T cells respond like Pep-/- T cells. These studies suggest that Pep-/- T cells in the context of a susceptible microenvironment can drive hyper-responsive CD45 E613R B cells to break tolerance.

De novo T-lymphocyte responses against baculovirus-derived recombinant influenzavirus hemagglutinin generated by a naive umbilical cord blood model of dendritic cell vaccination

Cancer patients and recipients of hematopoietic stem cell transplantation exhibit a negligible response to influenza vaccine. Toward the goal of addressing this issue, we developed an in vitro model of dendritic cell (DC) immunotherapy utilizing DCs generated from naïve umbilical cord blood (UCB). UCB DCs were loaded with purified rHA protein and used to stimulate autologous T-lymphocytes. Upon recall with HA-loaded autologous DC, a 4-10-fold increase in the number of IFN-gamma producing T-lymphocytes was observed in comparison to T-cells stimulated with control DCs. Antigen-specific T-cell functionality was determined by (51)Cr lytic assay. Using a peptide library of predicted HA binding epitopes, we mapped an HA-specific, DR15-restricted CD4 T-cell epitope and observed tetramer positive cells. This model demonstrates that HA-specific immune responses might possibly be generated in a de novo fashion and suggests that dendritic cell immunotherapy for the prevention of influenza in populations of immunosuppressed individuals could be feasible.

Evaluation of aseptic loosening of knee prostheses by quantitative bone scintigraphy

In not infected knee prostheses bone scintigraphy is a possible method to diagnose mechanical loosening, and therefore, to affect treatment regimes in symptomatic patients. However, hitherto studies showed controversial results for the reliability of bone scintigraphy in diagnosing loosened knee prostheses by using asymptomatic control groups. Therefore, the AIM of our study was to optimize the interpretation procedure and to evaluate the accuracy using results from revision surgery as standard.

METHODS

Retrospectively, we were able to examine the tibial component in 31 cemented prostheses. In this prostheses infection was excluded by histological or bacteriological examination during revision surgery. To quantify bone scintigraphy, we used medial and lateral tibial regions with a reference region from the contralateral femur.

RESULTS

To differentiate between loosened and intact prostheses we found a threshold of 5.0 for the maximum tibia to femur ratio of the both tibial regions and a threshold of 18% for the difference of the ratio of both tibial regions. Using these thresholds, values of 0.9, 1, 0.85, 1, and 0.94 were calculated for sensitivity, specificity, negative predictive value, positive predictive value, and accuracy, respectively. To get a sensitivity of 1, we found a lower threshold of 3.3 for the maximum tibia to femur ratio.

CONCLUSION

Quantitative bone scintigraphy appears to be a reliable diagnostic tool for aseptic loosening of knee prostheses with thresholds evaluated by revision surgery results being the golden standard.

Overcoming T cell-mediated rejection of bone marrow allografts by T-regulatory cells: synergism with veto cells and rapamycin

Recently, we have shown that anti-third-party cytotoxic T lymphocytes (CTLs) depleted of alloreactivity against the host are endowed with marked veto activity and can facilitate bone marrow (BM) allografting without graft-versus-host disease. We also demonstrated synergism between rapamycin (RAPA) and the veto cells. CD4(+)CD25(+) T-regulatory (Treg) cells are suppressor cells that can enhance alloengraftment. We investigated whether donor Tregs would be synergistic with veto CTLs and RAPA in augmenting alloengraftment or, conversely, would suppress veto CTL effects. Lethally irradiated C3H mice were transplanted at day 2 after irradiation with Balb-nude BM. Graft rejection was induced by purified host-type T cells infused 1 day prior to BMT. The addition of Tregs led to moderate enhancement of engraftment. RAPA at different doses was synergistic with Tregs. The addition of veto CTLs to Tregs enabled reducing the effective RAPA dose fourfold. Combining all three agents was necessary to overcome rejection at low-dose RAPA. Chimerism analysis at 5 to 9 months revealed a significant presence of host-type cells coexisting with the predominant donor T cells, suggesting that tolerance had been attained. The synergistic effects between Tregs, veto CTLs, and RAPA offer an attractive approach for facilitating alloengraftment.

Tolerance induction by third-party "off-the-shelf" CD4+CD25+ Treg cells

OBJECTIVE

Recent reports have shown that donor or host CD4(+)CD25(+) Treg cells can be used to control GVHD or graft rejection following allogeneic BMT in mice. In the present study we investigated the potential of third-party Treg cells compared to donor-type cells to facilitate BM allografting.

METHODS

Graft rejection is assessed in a mouse model of T cell-mediated BM allograft rejection. Lethally irradiated C3H mice are transplanted at day 2 after irradiation with T cell-depleted Balb/Nude BM. Graft rejection is induced by purified host-type T cells infused one day prior to BMT. Cells tested for their facilitating activity are added to the T cell-depleted BM allograft.

RESULTS

Naïve or ex vivo-expanded third-party Treg cells can effectively enhance engraftment of T cell-depleted BM allografts, exhibiting reactivity in vitro and in vivo similar to that found for donor-type Treg cells.

CONCLUSION

The use of third-party Treg cells in contrast to donor-type cells could allow advanced preparation of a large bank of Treg cells (off-the-shelf), with all the appropriate quality controls required for cell therapy.

[Radiation synovectomy of the knee joint: Evaluation of bremsstrahlung-detection by using a corpse phantom]

AIM

Multiple procedures for the quantification of activity leakage in radiation synovectomy of the knee joint have been described in the literature. We compared these procedures considering the real conditions of dispersion and absorption using a corpse phantom.

METHODS

We simulated different distributions of the activity in the knee joint and a different extra-articular spread into the inguinal lymph nodes. The activity was measured with a gamma-camera. Activity leakage was calculated by measuring the retention in the knee joint only using an anterior view, using the geometric mean of anterior and posterior views, or using the sum of anterior and posterior views. The same procedures were used to quantify the activity leakage by measuring the activity spread into the inguinal lymph nodes. In addition, the influence of scattered rays was evaluated.

RESULTS

For several procedures we found an excellent association with the real activity leakage, shown by an r(2) between 0.97 and 0.98. When the real value of the leakage is needed, e. g. in dosimetric studies, simultaneously measuring of knee activity and activity in the inguinal lymph nodes in anterior and posterior views and calculation of the geometric mean with exclusion of the scatter rays was found to be the procedure of choice.

CONCLUSION

When measuring of activity leakage is used for dosimetric calculations, the above-described procedure should be used. When the real value of the leakage is not necessary, e. g. for comparing different therapeutic modalities, several of the procedures can be considered as being equivalent.

Radiation synovectomy of the knee joint

Aim: Multiple procedures for the quantification of activity leakage in radiation synovectomy of the knee joint have been described in the literature. We compared these procedures considering the real conditions of dispersion and absorption using a corpse phantom. Methods: We simulated different distributions of the activity in the knee joint and a different extra-articular spread into the inguinal lymph nodes. The activity was measured with a gammacamera. Activity leakage was calculated by measuring the retention in the knee joint only using an anterior view, using the geometric mean of anterior and posterior views, or using the sum of anterior and posterior views. The same procedures were used to quantify the activity leakage by measuring the activity spread into the inguinal lymph nodes. In addition, the influence of scattered rays was evaluated. Results: For several procedures we found an excellent association with the real activity leakage, shown by an r² between 0.97 and 0.98. When the real value of the leakage is needed, e. g. in dosimetric studies, simultaneously measuring of knee activity and activity in the inguinal lymph nodes in anterior and posterior views and calculation of the geometric mean with exclusion of the scatter rays was found to be the procedure of choice. Conclusion: When measuring of activity leakage is used for dosimetric calculations, the above-described procedure should be used. When the real value of the leakage is not necessary, e. g. for comparing different therapeutic modalities, several of the procedures can be considered as being equivalent.

Electronic structure of metal-semiconductor nanojunctions in gold CdSe nanodumbbells

The electronic properties of metal-semiconductor nanojunctions are investigated by scanning tunneling spectroscopy of gold-tipped CdSe rods. A gap similar to that in bare CdSe nanorods is observed near the nanodumbbell center, while subgap structure emerges near the metal-semiconductor nanocontact. This behavior is attributed to the formation of subgap interface states that vanish rapidly towards the center of the rod, consistent with theoretical predictions. These states lead also to modified Coulomb staircase, and in some cases to negative differential conductance, on the gold tips.

Clara cell protein and surfactant protein�B in garbage collectors and in wastewater workers exposed to bioaerosols

OBJECTIVES

Inhalation of bioaerosols has been hypothesised to cause "toxic pneumonitis" that should increase lung epithelial permeability at the bronchioloalveolar level. Serum Clara cell protein (CC16) and serum surfactant protein B (SPB) have been proposed as sensitive markers of lung epithelial injury. This study was aimed at looking for increased lung epithelial permeability by determining CC16 and SPB in workers exposed to bioaerosols from wastewater or garbage.

METHODS

Subjects (778 wastewater, garbage and control workers; participation 61%) underwent a medical examination, lung function tests [American Thoracic Society (ATS) criteria], and determination of CC16 and SPB. Symptoms of endotoxin exposure and several potential confounders (age, gender, smoking, kidney function, obesity) were looked for. Results were examined with multiple linear or logistic regression.

RESULTS

Exposure to bioaerosols increased CC16 concentration in the wastewater workers. No effect of exposure on SPB was found. No clue to work-related respiratory diseases was found.

CONCLUSIONS

The increase in CC16 in serum supports the hypothesis that bioaerosols cause subclinical "toxic pneumonitis", even at low exposure.

A randomized double-blind placebo-controlled clinical trial of a product containing ephedrine, caffeine, and other ingredients from herbal sources for treatment of overweight and obesity in the absence of lifestyle treatment

OBJECTIVE

To evaluate the efficacy and side effects of an herbal formulation to promote weight loss, as compared to placebo.

DESIGN

12-week multicenter double-blind, placebo-controlled, randomized parallel groups design. Study conducted at three clinical sites in New York State. Subjects were randomized to receive either the 'active' product or a 'placebo' supplement for 12 weeks. Minimal steps were taken to influence lifestyle changes with regard to diet or exercise.

SUBJECTS

102 overweight/obese (30<BMI</=39.9 kg/m(2)) volunteers between the ages of 18 and 65 y.

MAIN OUTCOME MEASURES

Weight, percent body fat, fat mass, waist circumference, BMI, blood pressure, and pulse measured at 2 days, 1 week, 2 weeks, 4 weeks, 8 weeks, and 12 weeks postrandomization.

RESULTS

Subjects receiving the 'active' treatment experienced, on average, an additional 1.5 kg of weight loss compared with subjects receiving the placebo. In addition, subjects receiving the 'active' treatment experienced greater reductions in BMI and waist circumference over the 12-week period. No differences were observed with respect to percent body fat, fat mass, diastolic or systolic blood pressure, pulse, the occurrence of any adverse event, or the occurrence of any presumed treatment-related adverse event. Testing of the study product by two independent laboratories indicated that it had only approximately half of the intended amount of ephedrine alkaloids and caffeine.

CONCLUSIONS

Over the 12-week trial, subjects on the active treatment experienced significantly greater weight loss than subjects on placebo, without an increase in blood pressure, pulse, or the rate of adverse events. These benefits were achieved in the absence of any lifestyle treatment to change dietary or exercise behavior and with lower doses of ephedrine alkaloids and caffeine than those commonly utilized.

Hepatitis E, Helicobacter pylori, and gastrointestinal symptoms in workers exposed to waste water

BACKGROUND

Workers exposed to sewage may have an increased risk of infection by Helicobacter pylori and hepatitis E virus (HEV).

AIMS

To assess the prevalence of clinical hepatitis E (HE) and peptic ulcer disease as well as the seroprevalence of antibodies to H pylori and HEV in workers with and without sewage exposure and to look for symptoms due to exposure to endotoxin.

METHODS

In the first year of a prospective cohort study 349 sewage exposed workers and 429 municipal manual workers (participation: 61%) underwent a complete medical examination. Travelling to endemic areas, socioeconomic level, age, country in which childhood was spent, and number of siblings were considered as the main confounding factors.

RESULTS

Peptic ulcer disease and clinical HE did not occur more often in workers exposed to sewage. Prevalence of antibodies to HEV was 3.3% and overall prevalence of IgG antibodies to H pylori was 42% with large differences between subgroups. Logistic regression did not show an increased risk of seropositivity or antibodies to parietal cells in sewage exposed workers, but disentangling the effect of exposure from that of confounders was extremely difficult. No increase of symptoms due to exposure to endotoxin was found in sewage workers, with the exception of diarrhoea.

CONCLUSIONS

No clear increased risk of infection by H pylori or by HEV in workers exposed to sewage was found in this cross-sectional study, but these results need to be confirmed by follow up.

Abrogation of protein convertase 2 activity results in delayed islet cell differentiation and maturation, increased alpha-cell proliferation, and islet neogenesis

To date, the role of pancreatic hormones in pancreatic islet growth and differentiation is poorly understood. To address this issue, we examined mice with a disruption in the gene encoding prohormone convertase 2 (PC2). These mice are unable to process proglucagon, prosomatostatin, and other neuroendocrine precursors into mature hormones. Initiation of insulin (IN) expression during development was delayed in PC2 mutant mice. Cells containing IN were first detected in knockout embryos on d 15 of development, 5 d later than in wild-type littermates. However, the IN(+) cells of d 15 PC2 mutant mice coexpressed glucagon, as did the first appearing beta-cells of controls. In addition, lack of PC2 perturbed the pattern of expression of transcription factors presumed to be involved in the determination of the mature alpha-cell phenotype. Thus, in contrast to controls, alpha-cells of mutant mice had protracted expression of Nkx 6.1 and Pdx-1, but did not express Brn-4. Islets of adult mutant mice also contained cells coexpressing insulin and somatostatin, an immature cell type found only in islets of the wild-type strain during development. In addition to the effects on islet cell differentiation, the absence of PC2 activity resulted in a 3-fold increase in the rate of proliferation of proglucagon cells during the perinatal period. This increase contributed to the development of alpha-cell hyperplasia during postnatal life. Furthermore, the total beta-cell volume was increased 2-fold in adult mutants compared with controls. This increase was due to islet neogenesis, as the number of islets per section was significantly higher in knockout mice compared with wild-type mice, whereas both strains had similar rates of IN cell proliferation. These results indicate that hormones processed by PC2 affected processes that regulate islet cell differentiation and maturation in embryos and adults.

Insulinoma presenting with hyperandrogenism: a case report and a literature review

An 18-year-old woman presented with a 6-month history of amenorrhoea and hyperandrogenism. Three months later she developed several episodes of fasting hypoglycaemia and was subsequently diagnosed with an insulinoma. Hyperinsulinaemia was observed in association with an elevated serum testosterone level. Surgical removal of the insulinoma resulted in resolution of the clinical and biochemical features of the polycystic ovarian syndrome (PCOS). Polycystic ovarian syndrome is unusual in a patient having an insulinoma. The rarity of this association may be the result of the late age of onset of this type of tumour, intermittent secretion of excessive insulin by the tumour, the degree of hyperinsulinism or other factors extrinsic to the insulin receptor that may facilitate insulin activity. However, we could not discover how our patient differs in having had PCOS from the majority of women with insulinoma who do not. If other patients with insulinoma are subsequently found to have hyperandrogenism, then this tumour might be added to the differential diagnosis of causes of anovulatory cycles and hyperandrogenaemia, although rare the association would be uncommon.

[Lung diseases in persons exposed to waste disposal dust]

The current cohort study in the canton of Zurich is investigating respiratory diseases in waste collectors. Therefore, a clinical history was taken and lung function tests and measurement of the Clara cell protein concentration were carried out. The first results show no elevation of the prevalence of asthma or other lung diseases in waste collectors. Compared with control subjects, waste collectors have a lower forced expiratory volume in the first second and a higher mean Clara cell protein concentration. The prevalence of cardiovascular risk factors such as smoking, obesity and arterial hypertension which are not caused by the occupation is high. Indeed, about 50% of all participants are hypertensive.

[Hepatitis E and exposure to waste water]

Hepatitis E virus (HEV) is found in waste water which represents a route of infection. However, the risk for sewage workers is unknown. Thus, we aimed at determining the prevalence of anti-HEV antibodies in sewage workers from the Canton of Zurich. The anti-HEV antibodies evaluated in 288 subjects with exposure to sewage and 306 controls, a total of 594 subjects. Overall, twenty-two (3.7%) subjects had anti-HEV, the seroprevalence was similar in those exposed and controls. The most important risk factor, travelling in endemic areas, was lacking in two workers, who both were exposed to sewage. A follow up study in the population will soon give further evidence on the incidence rate.

[Staged diagnosis of septic hip endoprosthesis loosening with laboratory parameters and antigranulocyte scintigraphy]

AIM

The value of serial diagnosis of septic loosening of hip endoprosthesis using laboratory parameters and antigranulocytes scintigraphy was investigated and compared to joint aspiration.

METHOD

In 35 patients with intraoperative verification of infection, we calculated sensitivity, specify and prevalence dependent positive and negative predictive values for antigranulocyte scintigraphy, laboratory tests and the most suitable combination of both. We also calculated predictive values of joint aspiration using sensitivity and specify values given in the literature.

RESULTS

From negative and positive predictive values, of the sedimetation rate and leukocyte count provided no increase of information. We found the same result for positive predictive values of C-reactive protein. For antigranulocyte scintigraphy alone, we found a distinct but still unsatisfying increase of information. Nevertheless, in both cases infection could be excluded definitely. Therefore, the combination of C-reactive protein and antigranulocyte scintigraphy was suitable and the positive predictive values of this combination were only about 5% lower than those of joint aspiration. But with joint aspiration, infection could not be excluded.

CONCLUSION

A positive result in serial diagnosis using C-reactive protein and antigranulocyte scintigraphy leads to an distinct increase in the probability of infection which is comparable to that of joint aspiration. The additional advantages of this procedure are the certain exclusion of infection and the absence of invasiveness.

[Antigranulocyte scintigraphy of septic loosening of hip endoprosthesis: effect of different methods of analysis]

AIM

Diagnosis of infection with help of antigranulocyte scintigraphy near body stem is difficult because of contemporary visualisation of bone marrow. Therefore, we investigated, whether it is possible to improve the accuracy in diagnosing septic loosening of hip endoprosthesis by changing the analyzing methods.

METHODS

In 28 patients, the results of a visual interpretation of late scan, a visual interpretation and a quantitative interpretation of time-activity-course were compared. These results were verified by histology respectively microbiology.

RESULTS

Histological and microbiological verification found 14 septic loosening and 14 aseptic loosening of the hip prothesis. Therefore, sensitivity, specificity, negative and positive predictive value for the visual interpretation of late scan were 0.86, 0.57, 0.80 and 0.67. For visual and quantitative interpretation of time-activity-course we found 0.86, 0.79, 0.85 and 0.80 respectively 1, 0.93, 1, 0.93. For interobserver agreement we found kappa coefficients of 0.28 +/- 0.2 for visual interpretation of late scan, 0.48 +/- 0.17 for visual interpretation and 1.0 +/- 0 for quantitative interpretation of time-activity-course.

CONCLUSION

In all investigated values quantitative interpretation of time-activity-course was superior to the other analyzing methods. Therefore, antigranulocyte scintigraphy for septic loosening of hip endoprosthesis should be interpreted quantitatively.

Current practice of radioiodine treatment in the management of differentiated thyroid cancer in Germany

This prospective, observational study of a cohort of thyroid cancer patients in Germany focusses on the "real-world" practice in the management of thyroid cancer patients. This report includes data from 2376 patients with primary differentiated thyroid carcinoma first diagnosed in the year 1996. The study reveals considerable differences in actual practice concerning surgery and radioiodine treatment. The results indicate that consensus is lacking with respect to the multimodality treatment approach for differentiated thyroid carcinoma. Our analysis represents the most current and comprehensive national assessment of presenting patient characteristics, diagnostic tests, treatment and complications for thyroid cancer.

A scaffoldin of the Bacteroides cellulosolvens cellulosome that contains 11 type II cohesins

A cellulosomal scaffoldin gene, termed cipBc, was identified and sequenced from the mesophilic cellulolytic anaerobe Bacteroides cellulosolvens. The gene encodes a 2,292-residue polypeptide (excluding the signal sequence) with a calculated molecular weight of 242,437. CipBc contains an N-terminal signal peptide, 11 type II cohesin domains, an internal family III cellulose-binding domain (CBD), and a C-terminal dockerin domain. Its CBD belongs to family IIIb, like that of CipV from Acetivibrio cellulolyticus but unlike the family IIIa CBDs of other clostridial scaffoldins. In contrast to all other scaffoldins thus far described, CipBc lacks a hydrophilic domain or domain X of unknown function. The singularity of CipBc, however, lies in its numerous type II cohesin domains, all of which are very similar in sequence. One of the latter cohesin domains was expressed, and the expressed protein interacted selectively with cellulosomal enzymes, one of which was identified as a family 48 glycosyl hydrolase on the basis of partial sequence alignment. By definition, the dockerins, carried by the cellulosomal enzymes of this species, would be considered to be type II. This is the first example of authentic type II cohesins that are confirmed components of a cellulosomal scaffoldin subunit rather than a cell surface anchoring component. The results attest to the emerging diversity of cellulosomes and their component sequences in nature.

Comparison of HIG scintigraphy and bloodpool scintigraphy using HDP in arthritic joint disease

AIM

Because of a similar tracer accumulation, we assumed to get the same information about synovitis in arthritic joint disease with HIG scintigraphy and bloodpool scintigraphy using HDP. Therefore, we compared retrospectively 23 patients.

METHODS

In HIG scintigraphy, synovitis was diagnosed according to increasing activity from early to late image. In bloodpool scintigraphy according to an increased activity in comparison to the surrounding tissues.

RESULTS

In 694 joints comparison of both scintigraphic modalities was possible, resulting in a 2 x 2 kappa coefficient of 0.93 or 0.97 by using late-phase bone scintigraphy as an anatomical marker. For intra- and interobserver agreement, 2 x 2 kappa coefficients of 0.93 and 0.88 in HIG scintigraphy, respectively 0.96 and 0.90 in blood-pool scintigraphy were calculated.

CONCLUSION

This study shows an excellent agreement in the visualization of synovitis by HIG and bloodpool scintigraphy. Because of its higher objectivity and lower cost, investigation of synovitis should be performed by bloodpool scintigraphy.