Characterization of CD177-reactive iso- and auto-antibodies.

BACKGROUND: CD177 is a surface protein on neutrophils and a main mediator for the surface expression of proteinase 3 (PR3). Its functions are largely unknown. At least three types of antibodies have been described to target CD177: isoantibodies, which are formed in CD177-null individuals as a result of an immune reaction following transfusion or pregnancy; autoantibodies present in sera from patients with autoimmune neutropenia; and antineutrophil cytoplasmic antibodies in sera from patients with glomerulonephritis with polyangiitis. In this study, we aimed to compare the binding characteristics of auto- and iso-antibodies to optimize their detectability in the neutrophil serology laboratory. STUDY DESIGN AND METHODS: The reactivity of iso- and auto-antibodies against CD177 was studied using granulocytes, "native" CD177/PR3 complex, and recombinant CD177 or PR3. RESULTS: All iso- and auto-antibodies were reactive with CD177/PR3 when immobilized with monoclonal antibody (moab) 7D8. Seventy-five percent of autoantibodies, but none of the isoantibodies, did not react with CD177/PR3 immobilized with moab MEM166. The majority of autoantibodies did not react with recombinant CD177, whereas most isoantibodies tested positive. DISCUSSION: Our results suggest that iso- and auto-antibodies against CD177 target different epitopes. Isoantibodies mainly target CD177 alone, while the majority of autoantibodies target a native epitope present on the neutrophil surface, but absent from recombinant CD177 which lacks PR3. Moab MEM166 binds to the native epitope and hinders the binding of CD177 autoantibodies. The results may help to design diagnostic strategies, especially for the identification of autoantibodies.

IL-21+ CD4+ T helper cells co-expressing IFN-γ and TNF-α accumulate in the joints of antinuclear antibody positive patients with juvenile idiopathic arthritis.

Juvenile Idiopathic Arthritis (JIA) is currently classified into seven subgroups. Recently, antinuclear antibody (ANA) positive JIA patients were suggested to encompass a clinically homogenous new subgroup. CD4+ T helper (Th) cells play an essential role in JIA pathogenesis. Herein, we analyzed cytokine expression in synovial fluid (SF) CD4+ Th cells of JIA patients by using flow cytometry and compared cytokine patterns between JIA subgroups. We could show increased frequencies of IL-21 expressing CD4+ Th cells in the joints of ANA+ Oligo-/Poly-JIA patients, which co-expressed the Th-1 cytokines IFN-γ/TNF-α. In contrast, frequencies of IL-17 expressing cells were lowest in the joints of ANA+ Oligo-/Poly-JIA but enriched in that of ERA-JIA patients. This is the first description of a diverse SF Th cell cytokine pattern in different JIA subgroups. Additionally, we could define IL-21 as an effector cytokine expressed in SF Th cell in a significant proportion of ANA+ JIA patients.

Natural History of Perinatal and Infantile Hypophosphatasia: A Retrospective Study.

OBJECTIVE: To report clinical characteristics and medical history data obtained retrospectively for a large cohort of pediatric patients with perinatal and infantile hypophosphatasia. STUDY DESIGN: Medical records from academic medical centers known to diagnose and/or treat hypophosphatasia were reviewed. Patients born between 1970 and 2011 with hypophosphatasia and any of the following signs/symptoms at age <6 months were eligible: vitamin B6-dependent seizures, respiratory compromise, or rachitic chest deformity (NCT01419028). Patient demographics and characteristics, respiratory support requirements, invasive ventilator-free survival, and further complications of hypophosphatasia were followed for up to the first 5 years of life. RESULTS: Forty-eight patients represented 12 study sites in 7 countries; 13 patients were alive, and 35 were dead (including 1 stillborn). Chest deformity, respiratory distress, respiratory failure (as conditioned by the eligibility criteria), failure to thrive, and elevated calcium levels were present in >70% of patients between birth and age 5 years. Vitamin B6-dependent seizures and respiratory distress and failure were associated significantly (P < .05) with the risk of early death. Serum alkaline phosphatase activity in all 41 patients tested (mean [SD]: 18.1 [15.4] U/L) was below the mean lower limit of normal of the reference ranges of the various laboratories (88.2 U/L). Among the 45 patients with relevant data, 29 had received respiratory support, of whom 26 had died at the time of data collection. The likelihood of invasive ventilator-free survival for this cohort decreased to 63% at 3 months, 54% at 6 months, 31% at 12 months, and 25% at 5 years. CONCLUSIONS: Patients with perinatal or infantile hypophosphatasia and vitamin B6-dependent seizures, with or without significant respiratory distress or chest deformities, have high morbidity and mortality in the first 5 years of life. TRIAL REGISTRATION: ClinicalTrials.gov: NCT01419028.

[Fractures and bone mineral density in childhood]. / Frakturen und Knochendichte im Kindesalter.

BACKGROUND: In juvenile idiopathic arthritis and related chronic inflammatory diseases, proinflammatory cytokines inhibit bone formation and stimulate bone resorption. Anti-inflammatory drugs, such as glucocorticoids and nonsteroidal antirheumatic drugs (NSARD) have as a side effect the potential to inhibit growth and maintenance of bone. These issues are of particular importance for the growing skeleton in childhood and adolescence. OBJECTIVE: This article presents a narrative overview about the dimension of the problem, a critical evaluation of diagnostic procedures and a discussion of available countermeasures. METHODS: A systematic literature search was carried out and the available evidence was evaluated based on the authors' knowledge and clinical experience as experts in the field. RESULTS AND CONCLUSION: In recent years solid data have been accumulated with respect to the interpretation of bone mineral density (BMD) measurements in children and adolescents. Based on these data from the literature and given that the radiation exposure is also very low, it is now possible to clinically apply BMD measurements in this population using dual energy X­ray absorption (DXA) technology for risk evaluation and diagnosis, taking the respective phase of development and body length into consideration. Dynamic measurements over time appear to be especially valuable in the context of individual clinical data. Hence, BMD measurements can be helpful in monitoring bone health, especially in juvenile idiopathic arthritis and other related inflammatory diseases. Apart from the specific indications for extended diagnostics and bone targeted pharmacological treatment, this method can also contribute to the management of preventive measures, such as sufficient calcium and vitamin D intake and targeted exercise interventions. Even in times of extremely effective antirheumatic drugs, children with chronic inflammatory diseases still bear a risk for bone health.

Improvement of monoclonal antibody-immobilized granulocyte antigen assay for the detection of anti-HNA-1 alloantibodies.

BACKGROUND: Currently, the gold standard for the identification of antibodies against human neutrophil antigens (HNAs) is the monoclonal antibody-immobilized granulocyte antigen (MAIGA) assay. However, the handling of this assay is laborious and therefore cumbersome for the rapid screening of neutrophil antibodies. STUDY DESIGN AND METHODS: In this study, we simplified the performance of the conventional MAIGA procedure and approved it for the identification of anti-HNA-1 with HNA-1-typed neutrophils and stable transfected (HEK293) cell line expressing HNA-1a, -1b, and -1c. RESULTS: In contrast to the conventional MAIGA, all working steps including the incubation of antibodies with cells, washings, cell lysis, and subsequent antibody detection could be performed on microtiter plates. This modification accelerates the work schedule of MAIGA and reduces pipetting errors. Comparison between both assay performances using neutrophils as target showed concordant results. Subsequently, stable mammalian cell lines were tested. In comparison to neutrophils, cell lines were stable for a longer period of time (>4 weeks) and results obtained with these cell lines showed better interassay precision. Analysis of different FcγRIIIb capture monoclonal antibodies (MoAbs) for the MAIGA assay showed that MoAb LNK16 is superior for the detection of anti-HNA-1a, -1b, and -1c, whereas MoAb 3G8 showed false-negative results, caused by competitive inhibition of anti-HNA-1c alloantibodies. CONCLUSION: The modification of MAIGA and the use of transfected HEK293 cells improve the detection of anti-HNA-1 alloantibodies that may allow screening analysis in large cohort of samples.

Recombinant Enzyme Replacement Therapy in Hypophosphatasia.

Hypophosphatasia (HPP) is a rare monogenetic and multisystemic disease with involvement of different organs, including bone, muscle, kidney, lung, gastrointestinal tract and the nervous system. The exact metabolic mechanisms of the effects of TNAP deficiency in different tissues are not understood in detail. There is no approved specific treatment for HPP; therefore symptomatic treatment in order to improve the clinical features is of major interest. Enzyme replacement therapy (ERT) is a relatively new type of treatment based on the principle of administering a medical treatment replacing a defective or absent enzyme. Recently ERT with a bone targeted recombinant human TNAP molecule has been reported to be efficient in ten severely affected patients and improved survival of life threatening forms. These results are very promising especially with regard to the skeletal phenotype but it is unclear whether ERT also has beneficial effects for craniosynostosis and in other affected tissues in HPP such as brain and kidney. Long-term data are not yet available and further systematic clinical trials are needed. It is also necessary to establish therapeutic approaches to help patients who are affected by less severe forms of HPP but also suffer from a significant reduction in quality of life. Further basic research on TNAP function and role in different tissues and on its physiological substrates is critical to gain a better insight in the pathogenesis in HPP. This and further experiences in new therapeutic strategies may improve the prognosis and quality of life of patients with all forms of HPP.

The Enantioselective Dakin-West Reaction.

Here we report the development of the first enantioselective Dakin-West reaction, yielding α-acetamido methylketones with up to 58 % ee with good yields. Two of the obtained products were recrystallized once to achieve up to 84 % ee. The employed methylimidazole-containing oligopeptides catalyze both the acetylation of the azlactone intermediate and the terminal enantioselective decarboxylative protonation. We propose a dispersion-controlled reaction path that determines the asymmetric reprotonation of the intermediate enolate after the decarboxylation.

Alcohol cross-coupling for the kinetic resolution of diols via oxidative esterification.

We present an organocatalytic C-O-bond cross-coupling strategy to kinetically resolve racemic diols with aromatic and aliphatic alcohols, yielding enantioenriched esters. This one-pot protocol utilizes an oligopeptide multicatalyst, m-CPBA as the oxidant, and N,N'-diisopropylcarbodiimide as the activating agent. Racemic acyclic diols as well as trans-cycloalkane-1,2-diols were kinetically resolved, achieving high selectivities and good yields for the products and recovered diols.

Understanding the fundamentals of redox mediators in Li-O2 batteries: a case study on nitroxides.

The development of aprotic lithium-oxygen (Li-O2) batteries suffers from high charging overvoltages. Dissolved redox mediators, like nitroxides, providing increased energy efficiency and longer lifetime are promising tools to overcome this challenge. Since this auspicious concept is still in its infancy, the underlying chemical reactions as well as the impact of the different (electro)chemical parameters are poorly understood. Herein, we derive an electrochemical model for the charging reactions, which is validated by potentiostatic measurements. The model elucidates the impact of the major factors including basic cell parameters and the chemical properties of the redox mediator. The model is applied to the promising class of nitroxides, which is systematically investigated by using derivatives of TEMPO (2,2,6,6-tetramethyl-1-piperidinyloxy), AZADO (2-azaadamantane-N-oxyl), and an azaphenalene based nitroxide. The nitroxides are electrochemically characterized by cyclic voltammetry and their performance as redox mediators is studied in Li-O2 batteries with an ether-based electrolyte. Based on the presented model, the charging profiles of the different nitroxide redox mediators are correlated with their molecular structures.

A standardized clinical and radiological follow-up of patients with chronic non-bacterial osteomyelitis treated with pamidronate.

OBJECTIVES: Chronic non-bacterial osteomyelitis (CNO) is an autoinflammatory disorder of the skeletal system. Treatment with NSAIDs is generally effective in the majority of patients, however, a sizeable proportion of patients have persistent disease and subsequent treatment strategies are required. The aim of this study was to characterise the clinical and radiological disease course in CNO patients treated with the bisphosphonate pamidronate (PAM). METHODS: Eight CNO patients refractory to NSAIDs, glucocorticoids and sulfasalazine were treated with 6 cycles of PAM in four-weekly intervals. The disease course was assessed by clinical examination and whole-body (WB) MRI at standardised time points during the treatment phase and in a 6 months follow-up. RESULTS: Seven patients were in complete clinical remission after 6 applications of PAM. WB MRIs showed regression of inflammatory lesions in 7 patients with complete remission in only one patient and partial remission in 6 patients. One patient developed radiological progression despite a marked improvement of clinical symptoms. In the follow-up after PAM therapy, 3 patients developed MRI confirmed relapse. Additional applications of PAM induced a sustained clinical remission and partial radiological response in two of them. Mild temporary adverse effects were noted in 5 patients. CONCLUSIONS: Our study highlights that PAM is effective in controlling clinical symptoms (e.g. pain) in CNO patients. However, subclinical bone inflammation was still detectable by MRI in most of the patients and disease progression was noticed in some patients after cessation of PAM.

Disease-specific T cell receptors maintain pathogenic T helper cell responses in postinfectious Lyme arthritis.

BACKGROUND: Antibiotic-Refractory Lyme Arthritis (ARLA) involves a complex interplay of T cell responses targeting Borrelia burgdorferi antigens succeeding towards autoantigens by epitope spreading. However, the precise molecular mechanisms driving the pathogenic T cell response in ARLA remain unclear. Our aim was to elucidate the molecular program of disease-specific Th cells. METHODS: Using flow cytometry, high-throughput T cell receptor (TCR) sequencing and scRNA-seq of CD4+ Th cells isolated from the joints of European ARLA patients, we aimed at inferring antigen specificity through unbiased analysis of TCR repertoire patterns, identifying surrogate markers for disease-specific TCRs and connecting TCR specificity to transcriptional patterns. RESULTS: PD-1hiHLA-DR+CD4+ effector T cells were clonally expanded within the inflamed joints and persisted throughout disease course. Among these cells, we identified a distinct TCRß motif restricted to HLA-DRB1*11 or *13 alleles. These alleles, being underrepresented in North American ARLA patients, were unexpectedly prevalent in our European cohort. The identified TCRß motif served as surrogate marker for a convergent TCR response specific to ARLA, distinguishing it from other rheumatic diseases. In the scRNA-seq dataset, the TCRß motif particularly mapped to peripheral T helper (TPH) cells displaying signs of sustained proliferation, continuous TCR signaling, and expressing CXCL13 and IFN-γ. CONCLUSION: By inferring disease-specific TCRs from synovial T cells we identified a convergent TCR response in the joints of ARLA patients that continuously fueled the expansion of TPH cells expressing a pathogenic cytokine effector program. The identified TCRs will aid in uncovering the major antigen targets of the maladaptive immune response. FUNDING: Supported by the German Research Foundation (DFG) MO 2160/4-1; the Federal Ministry of Education and Research (BMBF; Advanced Clinician Scientist-Program INTERACT; 01EO2108) embedded in the Interdisciplinary Center for Clinical Research (IZKF) of the University Hospital Würzburg; the German Center for Infection Research (DZIF; Clinical Leave Program; TI07.001_007) and the Interdisciplinary Center for Clinical Research (IZKF) Würzburg (Clinician Scientist Program, Z-2/CSP-30).

Comparison of magnetic resonance imaging and 99mTechnetium-labelled methylene diphosphonate bone scintigraphy in the initial assessment of chronic non-bacterial osteomyelitis of childhood and adolescents.

OBJECTIVES: To compare sensitivity of bone scintigraphy using 99mTechnetium-labelled methylene diphosphonate (Tc-99m MDP) and magnetic resonance imaging (MRI) in the detection of inflammatory bone lesions in patients with chronic non-bacterial osteomyelitis (CNO). METHODS: Tc-99m MDP bone scintigraphy and MRI were performed in 32 CNO patients at the time of diagnosis and compared regarding their sensitivity in detecting inflammatory lesions in symptomatic regions of the body. RESULTS: Inflammatory lesions could be detected in 40 out of the 54 (74.1%) symptomatic regions by bone scintigraphy and in 53 (98.1%) of these regions by MRI (p<0.001). Sensitivity of MRI compared to bone scintigraphy was superior in detecting lesions in the long bones of the thigh and the lower legs (100% vs. 78.4%, respectively, p<0.05). CONCLUSIONS: Bone scintigraphy does not seem to display the whole extent of the inflammatory process in CNO. Therefore, depending on clinical relevance, MRI rather than planar bone scintigraphy should be considered for the detection of CNO lesions at diagnosis.

Effect of Clonally Expanded PD-1high CXCR5-CD4+ Peripheral T Helper Cells on B Cell Differentiation in the Joints of Patients With Antinuclear Antibody-Positive Juvenile Idiopathic Arthritis.

OBJECTIVE: Antinuclear antibody (ANA)-positive juvenile idiopathic arthritis (JIA) is characterized by synovial B cell hyperactivity, but the precise role of CD4+ T cells in promoting local B cell activation is unknown. This study was undertaken to determine the phenotype and function of synovial CD4+ T cells that promote aberrant B cell activation in JIA. METHODS: Flow cytometry was performed to compare the phenotype and cytokine patterns of PD-1high CD4+ T cells in the synovial fluid (SF) of patients with JIA and T follicular helper cells in the tonsils of control individuals. TCRVB next-generation sequencing was used to analyze T cell subsets for signs of clonal expansion. The functional impact of these T cell subsets on B cells was examined in cocultures in vitro. RESULTS: Multidimensional flow cytometry revealed the expansion of interleukin-21 (IL-21) and interferon-γ (IFNγ)-coexpressing PD-1high CXCR5-HLA-DR+CD4+ T cells that accumulate in the joints of ANA-positive JIA patients. These T cells exhibited signs of clonal expansion with restricted T cell receptor clonotypes. The phenotype resembled peripheral T helper (Tph) cells with an extrafollicular chemokine receptor pattern and high T-bet and B lymphocyte-induced maturation protein 1 expression, but low B cell lymphoma 6 expression. SF Tph cells, by provision of IL-21 and IFNy, skewed B cell differentiation toward a CD21low/- CD11c+ phenotype in vitro. Additionally, SF Tph cell frequencies correlated with the appearance of SF CD21low/- CD11c+CD27-IgM- double-negative (DN) B cells in situ. CONCLUSION: Clonally expanded CD4+ Tph cells accumulate in the joints of ANA-positive JIA patients and, in particular, promote CD21low/- CD11c+ DN B cell differentiation. The expansion of Tph cells and DN B cells might reflect the autoimmune response in the joints of ANA-positive JIA patients.

CD21lo/-CD27-IgM- Double-Negative B Cells Accumulate in the Joints of Patients With Antinuclear Antibody-Positive Juvenile Idiopathic Arthritis.

Juvenile idiopathic arthritis (JIA) encompasses a heterogeneous group of diseases. The appearance of antinuclear antibodies (ANAs) in almost half of the patients suggests B cell dysregulation as a distinct pathomechanism in these patients. Additionally, ANAs were considered potential biomarkers encompassing a clinically homogenous subgroup of JIA patients. However, in ANA+ JIA patients, the site of dysregulated B cell activation as well as the B cell subsets involved in this process is still unknown. Hence, in this cross-sectional study, we aimed in an explorative approach at characterizing potential divergences in B cell differentiation in ANA+ JIA patients by assessing the distribution of peripheral blood (PB) and synovial fluid (SF) B cell subpopulations using flow cytometry. The frequency of transitional as well as switched-memory B cells was higher in PB of JIA patients than in healthy controls. There were no differences in the distribution of B cell subsets between ANA- and ANA+ patients in PB. However, the composition of SF B cells was different between ANA- and ANA+ patients with increased frequencies of CD21lo/-CD27-IgM- "double negative" (DN) B cells in the latter. DN B cells might be a characteristic subset expanding in the joints of ANA+ JIA patients and are potentially involved in the antinuclear immune response in these patients. The results of our explorative study might foster further research dissecting the pathogenesis of ANA+ JIA patients.

Tissue-Nonspecific Alkaline Phosphatase-A Gatekeeper of Physiological Conditions in Health and a Modulator of Biological Environments in Disease.

Tissue-nonspecific alkaline phosphatase (TNAP) is a ubiquitously expressed enzyme that is best known for its role during mineralization processes in bones and skeleton. The enzyme metabolizes phosphate compounds like inorganic pyrophosphate and pyridoxal-5'-phosphate to provide, among others, inorganic phosphate for the mineralization and transportable vitamin B6 molecules. Patients with inherited loss of function mutations in the ALPL gene and consequently altered TNAP activity are suffering from the rare metabolic disease hypophosphatasia (HPP). This systemic disease is mainly characterized by impaired bone and dental mineralization but may also be accompanied by neurological symptoms, like anxiety disorders, seizures, and depression. HPP characteristically affects all ages and shows a wide range of clinical symptoms and disease severity, which results in the classification into different clinical subtypes. This review describes the molecular function of TNAP during the mineralization of bones and teeth, further discusses the current knowledge on the enzyme's role in the nervous system and in sensory perception. An additional focus is set on the molecular role of TNAP in health and on functional observations reported in common laboratory vertebrate disease models, like rodents and zebrafish.

Pediatric hypophosphatasia: lessons learned from a retrospective single-center chart review of 50 children.

BACKGROUND: Hypophosphatasia (HPP) is a rare, inherited metabolic disorder caused by loss-of-function mutations in the ALPL gene that encodes the tissue-nonspecific alkaline phosphatase TNAP (ORPHA 436). Its clinical presentation is highly heterogeneous with a remarkably wide-ranging severity. HPP affects patients of all ages. In children HPP-related musculoskeletal symptoms may mimic rheumatologic conditions and diagnosis is often difficult and delayed. To improve the understanding of HPP in children and in order to shorten the diagnostic time span in the future we studied the natural history of the disease in our large cohort of pediatric patients. This single centre retrospective chart review included longitudinal data from 50 patients with HPP diagnosed and followed at the University Children's Hospital Wuerzburg, Germany over the last 25 years. RESULTS: The cohort comprises 4 (8%) perinatal, 17 (34%) infantile and 29 (58%) childhood onset HPP patients. Two patients were deceased at the time of data collection. Diagnosis was based on available characteristic clinical symptoms (in 88%), low alkaline phosphatase (AP) activity (in 96%), accumulating substrates of AP (in 58%) and X-ray findings (in 48%). Genetic analysis was performed in 48 patients (31 compound heterozygous, 15 heterozygous, 2 homozygous mutations per patient), allowing investigations on genotype-phenotype correlations. Based on anamnestic data, median age at first clinical symptoms was 3.5 months (min. 0, max. 107), while median time to diagnosis was 13 months (min. 0, max. 103). Common symptoms included: impairment of motor skills (78%), impairment of mineralization (72%), premature loss of teeth (64%), musculoskeletal pain and craniosynostosis (each 64%) and failure to thrive (62%). Up to now 20 patients started medical treatment with Asfotase alfa. CONCLUSIONS: Reported findings support the clinical perception of HPP being a chronic multi-systemic disease with often delayed diagnosis. Our natural history information provides detailed insights into the prevalence of different symptoms, which can help to improve and shorten diagnostics and thereby lead to an optimised medical care, especially with promising therapeutic options such as enzyme-replacement-therapy with Asfotase alfa in mind.

Correction to: Physical activity and health-related quality of life in chronic non-bacterial osteomyelitis.

Following publication of the original article [1], we have been notified that the authors' first names and last names are presented in wrong order. The presentation of names, thus, should be as follows.

Efficacy and Safety of Asfotase Alfa in Infants and Young Children With Hypophosphatasia: A Phase 2 Open-Label Study.

CONTEXT: Long-term data on enzyme replacement treatment of hypophosphatasia (HPP) are limited. OBJECTIVE: To evaluate efficacy and safety of asfotase alfa in patients aged ≤5 years with HPP followed for up to 6 years. DESIGN: Phase 2 open-label study (July 2010 to September 2016). SETTING: Twenty-two sites; 12 countries. PARTICIPANTS: Sixty-nine patients [median (range) age: 16.0 (0.02 to 72) months] with severe HPP and sign/symptom onset before age 6 months. INTERVENTION: Asfotase alfa 2 mg/kg three times/week or 1 mg/kg six times/week subcutaneously. MAIN OUTCOME MEASURES: Primary efficacy measure: Radiographic Global Impression of Change (RGI-C) score [-3 (severe worsening) to +3 (complete/near-complete healing)]. Additional outcome measures: respiratory status, growth, and safety. Post hoc analysis: characteristics of radiographic responders vs nonresponders at Year 1 (RGI-C: ≥+2 vs <+2). RESULTS: During median (minimum, maximum) 2.3 (0.02, 5.8) years of treatment, RGI-C scores improved significantly at Month 6 [+2.0 (-1.7, +3.0)], Year 1 [+2.0 (-2.3, +3.0)], and Last Assessment [+2.3 (-2.7, +3.0); P < 0.0001 all]. Of 24 patients requiring respiratory support at Baseline, 11 (46%) no longer needed support. Height/weight z scores generally increased. Nine patients died (13%). All patients experienced at least one adverse event; pyrexia was most common. Compared with responders [n = 50 (72%)], nonresponders [n = 19 (28%)] had more severe disease at Baseline and a higher rate of neutralizing antibodies (NAbs) at Last Assessment. CONCLUSIONS: Most infants/young children given asfotase alfa showed early radiographic and clinical improvement sustained up to 6 years; radiographic nonresponders had more severe disease and more frequent NAbs at Last Assessment.

Locoregional recurrence and death from medullary thyroid carcinoma in a contemporaneous series: 5-year results.

OBJECTIVE: Studies of outcome in patients with medullary thyroid carcinoma require long follow-ups to accrue enough cancer-specific events. Owing to time-dependent changes in diagnosis and therapy, long observation periods render studies susceptible to 'time bias' which can yield spurious results. This study was designed to investigate cancer-specific event rates after initial neck resection in contemporaneous patients recruited within less than a decade. DESIGN: Institutional cohort study of 128 consecutive patients who underwent compartment-oriented neck surgery between 1994 and 2002 at a tertiary surgical center for hitherto untreated medullary thyroid carcinoma. METHODS: The Kaplan-Meier method was used in conjunction with the log-rank test for analysis of time-dependent outcomes. RESULTS: Follow-up was available for 120 patients (94%) including 63 rearranged during transfection (RET) carriers. There were six locoregional recurrences in the 110 patients with clear surgical margins at initial neck resection, and 12 cancer-specific deaths in the 120 patients with available follow-up. On Kaplan-Meier analysis, most clinicopathological variables were significantly associated with recurrence-free survival and cancer-specific survival. Within the median observation period of 64.5 months, patients with node-negative tumors did not develop locoregional recurrence or die from their malignancies. The low event rates precluded multivariate analyses with all clinicopathological variables. With our extensive surgical approach, median recurrence-free survival and cancer-specific survival at 5 years were 95.2 and 89.3% respectively. DISCUSSION: Compared with literature data, our 5-year locoregional recurrence rate of 4.8% appeared very favorable, and our 5-year cancer-specific mortality rate of 10.7% was among the lowest ever reported. The growing proportion of localized medullary thyroid carcinomas among contemporaneous patients can be expected to ultimately lower the event rates, complicating future studies of outcome.

A homozygous intronic branch-point deletion in the ALPL gene causes infantile hypophosphatasia.

Hypophosphatasia (HPP) is a multi-systemic inborn disease with an extraordinary spectrum of severity, ranging from the absence of mineralization to high lethality and it involves different organs including bone, muscle, kidney, lung, gastrointestinal tract and the nervous system. The disease is characterized by low levels of serum alkaline phosphatase, caused by loss-of-function mutations within the ALPL gene that encodes the tissue-nonspecific alkaline phosphatase TNAP. Here we present the functional characterization of a gene mutation, detected in intron 7 of the ALPL gene of a boy with infantile HPP in whom routine sequencing of the coding region failed to detect any mutation. The homozygous c.793del-14_33 mutation results in the loss of the branch-point motif, relevant for correct ALPL pre-mRNA splicing. The main transcript skips exon 8 and codes for a C-terminally truncated TNAP protein of 275 amino acids, which was detected in peripheral blood mononuclear cells and serum from the patient. The functional characterization of recombinant TNAP275 revealed no enzymatic activity nor any dominant-negative effect, relevant for the heterozygous parents. Nevertheless correct pre-mRNA splicing can take place without the branch-point sequence to a limited extend, as concluded from the ALPL cDNA, obtained from patient's PBMC, and from the low serum AP activity. These data reaffirm that in clear cut clinical cases, where conventional sequencing including the coding sequence and direct exon-intron-boundaries fails to detect mutations, deeper analyses of regulatory important motifs like branch-point sequences are required to establish a genetic diagnosis.