Whole cell hydride Meisenheimer complex biotransformation guided optimization of antimycobacterial benzothiazinones.

Nitrobenzothiazinones (BTZs) are potent active substances against Mycobacterium tuberculosis with currently two investigational drugs in clinical development for the treatment of tuberculosis. BTZs are the first examples for which a metabolic pathway towards transient hydride Meisenheimer complexes (HMC) has been shown in mammals, including humans. In this study, lead optimization efforts on BTZs are guided by the systematic evaluation of the HMC formation propensity combined with multiparameter assessment. For this purpose, a novel cell-based assay was specifically developed and fully implemented, and a library of 5- and 7-substituted BTZs was prepared to study substituent effects on the HMC formation. The multiparameter optimization revealed 5-methylated BTZs as the most preferred scaffolds, demonstrating a reduced HMC formation propensity combined with potent activity and good microsomal stability in vitro. In vivo experiments showed good systemic exposure upon oral administration and efficacy in a murine M. tuberculosis infection model. This study reports a qualified in vitro HMC assay, which not only enabled the selection of next-generation BTZs with improved pharmacokinetic properties but also allowed forecasting their in vivo metabolism.

Do Anti-tuberculosis Drugs Reach Their Target?─High-Resolution Matrix-Assisted Laser Desorption/Ionization Mass Spectrometry Imaging Provides Information on Drug Penetration into Necrotic Granulomas.

Tuberculosis (TB) is characterized by mycobacteria-harboring centrally necrotizing granulomas. The efficacy of anti-TB drugs depends on their ability to reach the bacteria in the center of these lesions. Therefore, we developed a mass spectrometry (MS) imaging workflow to evaluate drug penetration in tissue. We employed a specific mouse model that─in contrast to regular inbred mice─strongly resembles human TB pathology. Mycobacterium tuberculosis was inactivated in lung sections of these mice by γ-irradiation using a protocol that was optimized to be compatible with high spatial resolution MS imaging. Different distributions in necrotic granulomas could be observed for the anti-TB drugs clofazimine, pyrazinamide, and rifampicin at a pixel size of 30 µm. Clofazimine, imaged here for the first time in necrotic granulomas of mice, showed higher intensities in the surrounding tissue than in necrotic granulomas, confirming data observed in TB patients. Using high spatial resolution drug and lipid imaging (5 µm pixel size) in combination with a newly developed data analysis tool, we found that clofazimine does penetrate to some extent into necrotic granulomas and accumulates in the macrophages inside the granulomas. These results demonstrate that our imaging platform improves the predictive power of preclinical animal models. Our workflow is currently being applied in preclinical studies for novel anti-TB drugs within the German Center for Infection Research (DZIF). It can also be extended to other applications in drug development and beyond. In particular, our data analysis approach can be used to investigate diffusion processes by MS imaging in general.

Interleukin-13-Overexpressing Mice Represent an Advanced Preclinical Model for Detecting the Distribution of Antimycobacterial Drugs within Centrally Necrotizing Granulomas.

The Mycobacterium tuberculosis-harboring granuloma with a necrotic center surrounded by a fibrous capsule is the hallmark of tuberculosis (TB). For a successful treatment, antibiotics need to penetrate these complex structures to reach their bacterial targets. Hence, animal models reflecting the pulmonary pathology of TB patients are of particular importance to improve the preclinical validation of novel drug candidates. M. tuberculosis-infected interleukin-13-overexpressing (IL-13tg) mice develop a TB pathology very similar to patients and, in contrast to other mouse models, also share pathogenetic mechanisms. Accordingly, IL-13tg animals represent an ideal model for analyzing the penetration of novel anti-TB drugs into various compartments of necrotic granulomas by matrix-assisted laser desorption/ionization-mass spectrometry imaging (MALDI-MS imaging). In the present study, we evaluated the suitability of BALB/c IL-13tg mice for determining the antibiotic distribution within necrotizing lesions. To this end, we established a workflow based on the inactivation of M. tuberculosis by gamma irradiation while preserving lung tissue integrity and drug distribution, which is essential for correlating drug penetration with lesion pathology. MALDI-MS imaging analysis of clofazimine, pyrazinamide, and rifampicin revealed a drug-specific distribution within different lesion types, including cellular granulomas, developing in BALB/c wild-type mice, and necrotic granulomas in BALB/c IL-13tg animals, emphasizing the necessity of preclinical models reflecting human pathology. Most importantly, our study demonstrates that BALB/c IL-13tg mice recapitulate the penetration of antibiotics into human lesions. Therefore, our workflow in combination with the IL-13tg mouse model provides an improved and accelerated evaluation of novel anti-TB drugs and new regimens in the preclinical stage.

Integrating High-Resolution MALDI Imaging into the Development Pipeline of Anti-Tuberculosis Drugs.

Successful treatment of tuberculosis (TB) requires antibiotics to reach their intended point of action, i.e., necrotizing granulomas in the lung. MALDI mass spectrometry imaging (MSI) is able to visualize the distribution of antibiotics in tissue, but resolving the small histological structures in mice, which are most commonly used in preclinical trials, requires high spatial resolution. We developed a MALDI MSI method to image antibiotics in the mouse lung with high mass resolution (240k @ m/z 200 fwhm) and high spatial resolution (10 µm pixel size). A crucial step was to develop a cryosectioning protocol that retains the distribution of water-soluble drugs in small and fragile murine lung lobes without inflation or embedding. Choice and application of matrices were optimized to detect human-equivalent drug concentrations in tissue, and measurement parameters were optimized to detect multiple drugs in a single tissue section. We succeeded in visualizing the distribution of all current first-line anti-TB drugs (pyrazinamide, rifampicin, ethambutol, isoniazid) and the second-line drugs moxifloxacin and clofazimine. Four of these compounds were imaged for the first time in the mouse lung. Accurate mass identification was confirmed by on-tissue MS/MS. Evaluation of fragmentation pathways revealed the structure of the double-protonated molecular ion of pyrazinamide. Clofazimine was imaged for the first time with 10 µm pixel size revealing clofazimine accumulation in lipid deposits around airways. In summary, we developed a platform to resolve the detailed histology in the murine lung and to reliably detect a range of anti-TB drugs at human-equivalent doses. Our workflow is currently being employed in preclinical mouse studies to evaluate the efficacy of novel anti-TB drugs.

Results of a Phase 1/2 Study in Metastatic Renal Cell Carcinoma Patients Treated with a Patient-specific Adjuvant Multi-peptide Vaccine after Resection of Metastases.

Treatment of metastatic renal cell carcinoma comprises metastasectomy±systemic medical treatment. Specific immunotherapy after metastasectomy could be a complementary option. In this phase 1/2 study, safety and tolerability of an adjuvant multi-peptide vaccine (UroRCC) after metastasectomy was evaluated together with immune response and efficacy, compared with a contemporary cohort of patients (n=44) treated with metastasectomy only. Nineteen metastatic renal cell carcinoma patients received UroRCC via intradermal or subcutaneous application randomized to immunoadjuvants (granulocyte-macrophage colony-stimulating factor or Montanide). Adverse events of UroRCC were mainly grade I and II; frequency of immune response was higher for major histocompatibility complex class II peptides (17/19, 89.5%) than for major histocompatibility complex class I peptides (8/19, 42.1%). Median overall survival was not reached in the UroRCC group (mean: 112.6 mo, 95% confidence interval [CI]: 92.1-133.1) and 58.0 mo (95% CI: 32.7-83.2) in the control cohort (p=0.015). UroRCC was an independent prognosticator of overall survival (hazard ratio=0.19, 95% CI: 0.05-0.69, p=0.012). Adjuvant UroRCC multi-peptide vaccine after metastasectomy was well tolerated, immunogenic, and indicates potential clinical benefit when compared with a contemporary control cohort (NCT02429440). PATIENT SUMMARY: The application of a patient-specific peptide vaccine after complete resection of metastases in metastatic renal cell carcinoma patients resulted in favorable tolerability and outcome.

Metastasectomy for metastatic renal cell carcinoma in the era of modern systemic treatment: C-reactive protein is an independent predictor of overall survival.

OBJECTIVE: To define the predictive capability of serum C-reactive protein for a contemporary patient collective undergoing metastasectomy for metastatic renal cell carcinoma with access to modern targeted therapies. METHODS: A total of 88 patients treated with metastasectomy for metastatic renal cell carcinoma from 2003 to 2014 were evaluated for putative clinicopathological risk factors and survival. Kaplan-Meier analyses, univariate and multivariate testing were carried out. Receiver operating characteristic curve analysis was applied to evaluate available risk stratification instruments for patients undergoing metastasectomy. RESULTS: Median overall survival for the collective was 66.31 months (95% confidence interval 50.67-135.47; 5-year overall survival 55%). The median preoperative C-reactive protein level was 6.7 mg/L (range 0.1-161.7). A C-reactive protein cut-off value of 5 mg/dL was significantly discriminative of survival (P = 0.029). Median survival in dependence of C-reactive protein accounted for 50.67 months (range 33.86-63.05 months) in the C-reactive protein >5 mg/L group, and 135.47 months in the C-reactive protein ≤5 mg/L group (range 66.31-135.47 months). C-reactive protein elevation >5 mg/L, anemia and surgical margin status were identified as significant predictors of overall survival in univariate analysis. In a multivariate model, resection margin status (P = 0.015) and C-reactive protein elevation (P = 0.038) were confirmed as independent predictive variables. CONCLUSIONS: Elevated C-reactive protein >5 mg/L was identified as an independent predictor of survival in a contemporary patient collective undergoing metastasectomy for metastatic renal cell carcinoma. Future analyses and risk stratification tools for patients undergoing metastasectomy for metastatic renal cell carcinoma should aim to evaluate and include C-reactive protein. To overcome low patient numbers, multi-institutional studies should be carried out.

Cathepsin G in Experimental Tuberculosis: Relevance for Antibacterial Protection and Potential for Immunotherapy.

Neutrophil serine proteases, such as cathepsin G (CG) and neutrophil elastase (NE), have been implicated in the protective response against infections, including experimental mycobacterial infections. The goal of this study was to explore the role of CG in immunocompetent mice challenged aerogenically with Mycobacterium tuberculosis. We used genetically CG- or CG/NE-deficient mice to define the importance of these neutrophil serine proteases for antibacterial protection, granulomatous response, and survival. In addition, we explored the effect of intratracheally delivered liposomally encapsulated CG/NE as a therapeutic approach early during M. tuberculosis infection. Our data show that the presence of CG or CG/NE prolongs survival in M. tuberculosis-infected mice. However, CG is not directly involved in antibacterial defenses, and exogenous intratracheal administration of CG combined with NE does not reduce bacterial loads in the lungs of M. tuberculosis-infected mice.

Control of Mycobacterial Infections in Mice Expressing Human Tumor Necrosis Factor (TNF) but Not Mouse TNF.

Tumor necrosis factor (TNF) is an important cytokine for host defense against pathogens but is also associated with the development of human immunopathologies. TNF blockade effectively ameliorates many chronic inflammatory conditions but compromises host immunity to tuberculosis. The search for novel, more specific human TNF blockers requires the development of a reliable animal model. We used a novel mouse model with complete replacement of the mouse TNF gene by its human ortholog (human TNF [huTNF] knock-in [KI] mice) to determine resistance to Mycobacterium bovis BCG and M. tuberculosis infections and to investigate whether TNF inhibitors in clinical use reduce host immunity. Our results show that macrophages from huTNF KI mice responded to BCG and lipopolysaccharide similarly to wild-type macrophages by NF-κB activation and cytokine production. While TNF-deficient mice rapidly succumbed to mycobacterial infection, huTNF KI mice survived, controlling the bacterial burden and activating bactericidal mechanisms. Administration of TNF-neutralizing biologics disrupted the control of mycobacterial infection in huTNF KI mice, leading to an increased bacterial burden and hyperinflammation. Thus, our findings demonstrate that human TNF can functionally replace murine TNF in vivo, providing mycobacterial resistance that could be compromised by TNF neutralization. This new animal model will be helpful for the testing of specific biologics neutralizing human TNF.

Surface hydrolysis of sphingomyelin by the outer membrane protein Rv0888 supports replication of Mycobacterium tuberculosis in macrophages.

Sphingomyelinases secreted by pathogenic bacteria play important roles in host-pathogen interactions ranging from interfering with phagocytosis and oxidative burst to iron acquisition. This study shows that the Mtb protein Rv0888 possesses potent sphingomyelinase activity cleaving sphingomyelin, a major lipid in eukaryotic cells, into ceramide and phosphocholine, which are then utilized by Mtb as carbon, nitrogen and phosphorus sources, respectively. An Mtb rv0888 deletion mutant did not grow on sphingomyelin as a sole carbon source anymore and replicated poorly in macrophages indicating that Mtb utilizes sphingomyelin during infection. Rv0888 is an unusual membrane protein with a surface-exposed C-terminal sphingomyelinase domain and a putative N-terminal channel domain that mediated glucose and phosphocholine uptake across the outer membrane in an M. smegmatis porin mutant. Hence, we propose to name Rv0888 as SpmT (sphingomyelinase of Mycobacterium tuberculosis). Erythrocyte membranes contain up to 27% sphingomyelin. The finding that Rv0888 accounts for half of Mtb's hemolytic activity is consistent with its sphingomyelinase activity and the observation that Rv0888 levels are increased in the presence of erythrocytes and sphingomyelin by 5- and 100-fold, respectively. Thus, Rv0888 is a novel outer membrane protein that enables Mtb to utilize sphingomyelin as a source of several essential nutrients during intracellular growth.

Clade-specific virulence patterns of Mycobacterium tuberculosis complex strains in human primary macrophages and aerogenically infected mice.

UNLABELLED: In infection experiments with genetically distinct Mycobacterium tuberculosis complex (MTBC) strains, we identified clade-specific virulence patterns in human primary macrophages and in mice infected by the aerosol route, both reflecting relevant model systems. Exclusively human-adapted M. tuberculosis lineages, also termed clade I, comprising "modern" lineages, such as Beijing and Euro-American Haarlem strains, showed a significantly enhanced capability to grow compared to that of clade II strains, which include "ancient" lineages, such as, e.g., East African Indian or M. africanum strains. However, a simple correlation of inflammatory response profiles with strain virulence was not apparent. Overall, our data reveal three different pathogenic profiles: (i) strains of the Beijing lineage are characterized by low uptake, low cytokine induction, and a high replicative potential, (ii) strains of the Haarlem lineage by high uptake, high cytokine induction, and high growth rates, and (iii) EAI strains by low uptake, low cytokine induction, and a low replicative potential. Our findings have significant implications for our understanding of host-pathogen interaction and factors that modulate the outcomes of infections. Future studies addressing the underlying mechanisms and clinical implications need to take into account the diversity of both the pathogen and the host. IMPORTANCE: Clinical strains of the Mycobacterium tuberculosis complex (MTBC) are genetically more diverse than previously anticipated. Our analysis of mycobacterial growth characteristics in primary human macrophages and aerogenically infected mice shows that the MTBC genetic differences translate into pathogenic differences in the interaction with the host. Our study reveals for the first time that "TB is not TB," if put in plain terms. We are convinced that it is very unlikely that a single molecular mechanism may explain the observed effects. Our study refutes the hypothesis that there is a simple correlation between cytokine induction as a single functional parameter of host interaction and mycobacterial virulence. Instead, careful consideration of strain- and lineage-specific characteristics must guide our attempts to decipher what determines the pathological potential and thus the outcomes of infection with MTBC, one of the most important human pathogens.

Propionic acidemia: clinical course and outcome in 55 pediatric and adolescent patients.

BACKGROUND: Propionic acidemia is an inherited disorder caused by deficiency of propionyl-CoA carboxylase. Although it is one of the most frequent organic acidurias, information on the outcome of affected individuals is still limited. STUDY DESIGN/METHODS: Clinical and outcome data of 55 patients with propionic acidemia from 16 European metabolic centers were evaluated retrospectively. 35 patients were diagnosed by selective metabolic screening while 20 patients were identified by newborn screening. Endocrine parameters and bone age were evaluated. In addition, IQ testing was performed and the patients' and their families' quality of life was assessed. RESULTS: The vast majority of patients (>85%) presented with metabolic decompensation in the neonatal period. Asymptomatic individuals were the exception. About three quarters of the study population was mentally retarded, median IQ was 55. Apart from neurologic symptoms, complications comprised hematologic abnormalities, cardiac diseases, feeding problems and impaired growth. Most patients considered their quality of life high. However, according to the parents' point of view psychic problems were four times more common in propionic acidemia patients than in healthy controls. CONCLUSION: Our data show that the outcome of propionic acidemia is still unfavourable, in spite of improved clinical management. Many patients develop long-term complications affecting different organ systems. Impairment of neurocognitive development is of special concern. Nevertheless, self-assessment of quality of life of the patients and their parents yielded rather positive results.

What is the evidence for the use of adrenaline in the treatment of neonatal hypotension?

AIM: The authors of this review present the current evidence of the physiology, indications and use of adrenaline in neonates, with particular focus on the treatment of hypotension. METHOD: A structured literature search was performed across selected electronic databases, reference lists and related articles. Abstracts arising from the search were screened for relevance according to predefined inclusion criteria. Full articles for the selected abstracts were obtained and then reviewed. Articles were analysed through a two stage process until agreement was reached between the research team on the studies for inclusion. RESULTS: We identified 187 animal and human studies (published between 1924-2011) using various methodologies but with two main themes: the physiology of endogenous adrenaline in neonates and the therapeutic uses of this hormone in neonatal medicine. The physiological studies measured catecholamine levels in cord blood, neonatal urine and blood, some in response to interventions such as suctioning, skin massage or morphine infusion. Within the therapeutic studies there was only one randomised controlled trial (RCT): a comparison of dopamine versus adrenaline involving 60 infants of < 32 weeks gestational age. CONCLUSION: Despite the number of studies identified, we found few adequately-controlled studies on the therapeutic use of adrenaline in neonates. Future research should focus on RCTs comparing adrenaline to other commonly used inotropes.

Variant G57E of mannose binding lectin associated with protection against tuberculosis caused by Mycobacterium africanum but not by M. tuberculosis.

Structural variants of the Mannose Binding Lectin (MBL) cause quantitative and qualitative functional deficiencies, which are associated with various patterns of susceptibility to infectious diseases and other disorders. We determined genetic MBL variants in 2010 Ghanaian patients with pulmonary tuberculosis (TB) and 2346 controls and characterized the mycobacterial isolates of the patients. Assuming a recessive mode of inheritance, we found a protective association between TB and the MBL2 G57E variant (odds ratio 0.60, confidence interval 0.4-0.9, P 0.008) and the corresponding LYQC haplotype (P(corrected) 0.007) which applied, however, only to TB caused by M. africanum but not to TB caused by M. tuberculosis. In vitro, M. africanum isolates bound recombinant human MBL more efficiently than did isolates of M. tuberculosis. We conclude that MBL binding may facilitate the uptake of M. africanum by macrophages, thereby promoting infection and that selection by TB may have favoured the spread of functional MBL deficiencies in regions endemic for M. africanum.

Expression of the ompATb operon accelerates ammonia secretion and adaptation of Mycobacterium tuberculosis to acidic environments.

Homeostasis of intracellular pH is a trait critical for survival of Mycobacterium tuberculosis in macrophages. However, mechanisms by which M. tuberculosis adapts to acidic environments are poorly understood. In this study, we analysed the physiological functions of OmpATb, a surface-accessible protein of M. tuberculosis. OmpATb did not complement the permeability defects of a Mycobacterium smegmatis porin mutant to glucose, serine and glycerol, in contrast to the porin MspA. Uptake rates of these solutes were unchanged in an ompATb operon mutant of M. tuberculosis indicating that OmpATb is not a general porin. Chemical analysis of low-pH culture filtrates showed that the proteins encoded by the ompATb operon are involved in generating a rapid ammonia burst, which neutralized medium pH and preceded exponential growth of M. tuberculosis. Addition of ammonia accelerated growth of the ompATb operon mutant demonstrating that ammonia secretion is indeed a mechanism by which M. tuberculosis neutralizes acidic environments. Infection experiments revealed that the ompATb operon was not required for full virulence in mice suggesting that M. tuberculosis has multiple mechanisms of resisting phagosomal acidification. Taken together, these results show that the ompATb operon is necessary for rapid ammonia secretion and adaptation of M. tuberculosis to acidic environments in vitro but not in mice.

Mycobacterium tuberculosis embB codon 306 mutations confer moderately increased resistance to ethambutol in vitro and in vivo.

Ethambutol (EMB) is a major component of the first-line therapy of tuberculosis. Mutations in codon 306 of embB (embB306) were suggested as a major resistance mechanism in clinical isolates. To directly analyze the impact of individual embB306 mutations on EMB resistance, we used allelic exchange experiments to generate embB306 mutants of M. tuberculosis H37Rv. The level of EMB resistance conferred by particular mutations was measured in vitro and in vivo after EMB therapy by daily gavage in a mouse model of aerogenic tuberculosis. The wild-type embB306 ATG codon was replaced by embB306 ATC, ATA, or GTG, respectively. All of the obtained embB306 mutants exhibited a 2- to 4-fold increase in EMB MIC compared to the wild-type H37Rv. In vivo, the one selected embB306 GTG mutant required a higher dose of ethambutol to restrict its growth in the lung compared to wild-type H37Rv. These experiments demonstrate that embB306 point mutations enhance the EMB MIC in vitro to a moderate, but significant extent, and reduce the efficacy of EMB treatment in the animal model. We propose that conventional EMB susceptibility testing, in combination with embB306 genotyping, may guide dose adjustment to avoid clinical treatment failure in these low-level resistant strains.

NALP3 is not necessary for early protection against experimental tuberculosis.

In vitro, Toll-like receptors (TLR)2, 4 and 9 as well as NOD-like receptor 2 critically determine macrophage responses to Mycobacterium tuberculosis (Mtb) infection. However, in low-dose experimental murine tuberculosis, single or multiple deficiencies in TLRs 2, 4, 9 or NOD2 have little, if any, impact on early mycobacterial growth containment, granuloma formation and survival. Here, we analyzed the relevance of NALP3, one component of the danger-signaling inflammasome, for (i) Mtb-induced cytokine secretion in vitro and in vivo, (ii) restriction of Mtb replication in infected organs and (iii) granuloma formation. In the absence of functional NALP3, there was no IL-1beta and IL-18 production in Mtb-infected dendritic cells and macrophages in vitro, whereas secretion of IL-1alpha, IL-12p40 and TNF remained unaffected. After three weeks of infection, NALP3-deficient as well as IL-18-deficient mice were as capable as wildtype mice of restricting Mtb loads at a plateau level within well-differentiated granulomas. In conclusion, despite its involvement in cytokine processing, NALP3 is not essential for induction of protective immunity to Mtb.

Difficulties in diagnosis and treatment of 5alpha-reductase type 2 deficiency in a newborn with 46,XY DSD.

BACKGROUND/AIMS: Steroid 5alpha-reductase deficiency (MIM*607306) caused by mutations in the SRD5A2 gene is characterized by a predominantly female phenotype at birth and significant virilization at puberty. The undermasculinization at birth results from low dihydrotestosterone (DHT) levels during fetal development as the type 2 isoenzyme activity is reduced. In puberty, when the type 1 isoenzyme activity increases, significant virilization occurs. Most 46,XY individuals with 5alpha-reductase 2 deficiency develop a male gender identity. CASE REPORT AND RESULTS: We present a case with a predominantly female phenotype and ambiguous external genitalia but a normal 46,XY karyotype. Plasma steroid analysis after beta-hCG stimulation at 8 days of age revealed a steroid profile estimated as normal with a testosterone (T)/DHT ratio of 9.5 initially misleading to the exclusion of 5alpha-reductase deficiency. However, mutation analysis of the SRD5A2 gene revealed a homozygote point mutation (Leu55Gln) confirming the diagnosis of 5alpha-reductase deficiency. A male phenotype was successfully achieved by hormone treatment with T and DHT after diagnosing 5alpha-reductase deficiency and a masculinization operation. As a side effect skeletal age accelerated temporarily. CONCLUSION: In individuals with predominantly female phenotype and suspected 5alpha-reductase deficiency, a T/DHT ratio during the neonatal period >8.5 might point to 5alpha-reductase deficiency. After confirmation of the diagnosis by molecular analysis of the SRD5A2 gene, a satisfactory change to a male phenotype can be achieved by hormone treatment preceding surgery.

Kidney transplantation in patients with Fabry disease.

Little is known about the effects of enzyme replacement therapy (ERT) in kidney transplant recipients with Fabry disease. Clinical characteristics of transplant recipients in the Fabry Outcome Survey (FOS) were therefore examined in patients with Fabry disease with or without ERT. Of the 837 European patients in FOS (March 2006), 34 male patients and two female patients had received kidney transplants. Mean age at transplantation was 37.6 +/- 10.9 years, mean time since transplantation was 7.7 +/- 6.4 years, median estimated glomerular filtration rate (eGFR) was 44.4 ml/min/1.73 m(2), and median proteinuria was 296 mg/24 h. Of 27 patients with baseline data, 59% had hypertension, 74% had left ventricular hypertrophy, 22% had cardiac valve disease, 30% had arrhythmia, and 22% had transient ischaemic attacks and 15% stroke. Twenty patients (74%; two female patients, 18 male patients) were receiving ERT with agalsidase alfa. At enrollment or at the start of ERT, median eGFRs were 59 and 35 ml/min/1.73 m(2) (P = 0.05) and median proteinuria levels were 240 and 420 mg/24 h (not significant) in treated and untreated patients respectively. Renal function remained stable in patients receiving ERT. In conclusion, agalsidase alfa is well tolerated in patients with Fabry disease who have undergone renal transplantation.

In vitro and in vivo characterization of a Mycobacterium tuberculosis mutant deficient in glycosyltransferase Rv1500.

In Mycobacterium marinum, the homologue of Rv1500 of M. tuberculosis encodes a glycosyltransferase. Initially, it was suggested that this gene is involved in the synthesis of phosphatidylinositol mannosides (PIMs), generating Ac(2)PIM(7) from Ac(2)PIM(5). Phosphatidylinositol mannoside and its related compounds lipomannan (LM) and lipoarabinomannan (LAM) have been shown to modulate the host response to an infection with M. tuberculosis. Here, we generated a deletion mutant of Rv1500 in M. tuberculosis H37Rv, and analyzed the mutant using a biochemical approach as well as in vitro and in vivo infection models. Inactivation of Rv1500 did not lead to an altered expression pattern of PIMs in M. tuberculosis H37Rv. We found phosphatidylinositol (PI), PIM(2), AcPIM(2), Ac(2)PIM(2), and AcPIM(6) in both strains, but were unable to detect Ac(2)PIM(7) or Ac(2)PIM(5) either in the wild type or the mutant strain. Uptake and growth of H37Rv and Rv1500 mutant strains in murine bone marrow-derived macrophages was identical, and TNFalpha and IL-12p40 production in mouse macrophages and dendritic cells was induced to similar levels following infection with either strain. Aerosol challenge of mice showed that wild type and Rv1500 mutant strains had identical growth rates in infected organs over time. We verified mRNA expression of Rv1500 in H37Rv and conclude that Rv1500 must serve a redundant role in viability and virulence of M. tuberculosis.