Variability In Disease Progression Research Articles

Aβ seeds resist inactivation by formaldehyde.

Cerebral β-amyloidosis can be exogenously induced by the intracerebral injection of brain extracts containing aggregated β-amyloid (Aβ) into young, pre-depositing Aβ precursor protein- (APP) transgenic mice. Previous work has shown that the induction involves a prion-like seeding mechanism in which the seeding agent is aggregated Aβ itself. Here we report that the β-amyloid-inducing activity of Alzheimer's disease (AD) brain tissue or aged APP-transgenic mouse brain tissue is preserved, albeit with reduced efficacy, after formaldehyde fixation. Moreover, spectral analysis with amyloid conformation-sensitive luminescent conjugated oligothiophene dyes reveals that the strain-like properties of aggregated Aβ are maintained in fixed tissues. The resistance of Aβ seeds to inactivation and structural modification by formaldehyde underscores their remarkable durability, which in turn may contribute to their persistence and spread within the body. The present findings can be exploited to establish the relationship between the molecular structure of Aβ aggregates and the variable clinical features and disease progression of AD even in archived, formalin-fixed autopsy material.

The leukodystrophies.

Leukodystrophies are a group of genetically determined disorders that affect development or maintenance of central nervous system myelin. Leukodystrophies have a reported incidence of 1 in 7500 live births, but fewer than half of patients receive a specific diagnosis. In this review, the authors discuss types of leukodystrophies: their prevalence, clinical presentation, symptoms, and diagnosis, as well as current and future treatments. Diagnosis is based on a combination of history, exam, radiological, and laboratory findings, including genetic testing. Leukodystrophies can present at any age from infancy to adulthood, with variability in disease progression and clinical presentation, ranging from developmental delay to seizures to spasticity. Although there are few cures, there are significant opportunities for care and improvements in patient well-being. Their high prevalence, combined with rapid advances in imaging, genetics, and potential treatments, makes an understanding of the leukodystrophies necessary for care providers in genetics and neurology.

TM6SF2 rs58542926 influences hepatic fibrosis progression in patients with non-alcoholic fatty liver disease.

Non-alcoholic fatty liver disease (NAFLD) is an increasingly common condition, strongly associated with the metabolic syndrome, that can lead to progressive hepatic fibrosis, cirrhosis and hepatic failure. Subtle inter-patient genetic variation and environmental factors combine to determine variation in disease progression. A common non-synonymous polymorphism in TM6SF2 (rs58542926 c.449 C>T, p.Glu167Lys) was recently associated with increased hepatic triglyceride content, but whether this variant promotes clinically relevant hepatic fibrosis is unknown. Here we confirm that TM6SF2 minor allele carriage is associated with NAFLD and is causally related to a previously reported chromosome 19 GWAS signal that was ascribed to the gene NCAN. Furthermore, using two histologically characterized cohorts encompassing steatosis, steatohepatitis, fibrosis and cirrhosis (combined n=1,074), we demonstrate a new association, independent of potential confounding factors (age, BMI, type 2 diabetes mellitus and PNPLA3 rs738409 genotype), with advanced hepatic fibrosis/cirrhosis. These findings establish new and important clinical relevance to TM6SF2 in NAFLD.

IL-8 Gene Variants are Associated with Lung Function Decline and Multidimensional BODE Index in COPD Patients But Not with Disease Susceptibility: A Validation Study

Background and objective: COPD is a leading cause of dead worldwide and tobacco smoking is its major risk factor. IL8 is a proinflammatory chemokine mainly involved in the acute inflammatory reaction. The aim of this study was to test the association of IL-8, CXCR1 and CXCR2 gene variants and COPD susceptibility as part of a replication study and explore the effect of these variations in disease progression. Methods: 9 tagSNPs were genotyped in 728 Caucasian individuals (196 COPD patients, 80 smokers and 452 non-smoking controls). Pulmonary compromise was evaluated using spirometry and clinical parameters at baseline and annually over a 2 years period. We also determined plasma levels of TNF-α, IL-6, IL-8 and IL-16 in COPD patients. Results: There was a lack of association between gene variants or haplotypes with predisposition to COPD. No correlation was observed between the polymorphisms and cytokines levels. Interestingly, significant associations were found between carriers of the rs4073A (OR = 3.53, CI 1.34-9.35, p = 0.01), rs2227306C (OR = 5.65, CI 1.75–18.88, p = 0.004) and rs2227307T (OR = 4.52, CI = 1.49–12.82, p = 0.007) alleles in the IL-8 gene and patients who scored higher in the BODE index and showed an important decrease in their FEV1 and FVC during the 2 years follow-up period (p < 0.05). Conclusions: Despite no association was found between the studied genes and COPD susceptibility, three polymorphisms in the IL-8 gene appear to be involved in a worse progression of the disease, with an affectation beyond the pulmonary function and importantly, a reduction in lung function along the follow-up years.

High producer haplotype (CAG) of -863C/A, -308G/A and -238G/A polymorphisms in the promoter region of TNF-α gene associate with enhanced apoptosis of lymphocytes in HIV-1 subtype C infected individuals from North India.

IntroductionThe natural history of HIV-1 infection and its progression towards AIDS vary considerably among individuals. Host genetic factors may be one of the possible reasons for variable HIV-1 disease progression. Single nucleotide polymorphisms (SNPs) in the promoter region of TNF-α gene can influence its production. The aim of the present study was to determine the association of functional TNF-α SNPs and its associated parameters related to apoptosis that may influence the rate of HIV-1 disease progression.MethodsTherapy naive, 100 HIV slow progressors (SPs), 100 HIV fast progressors (FPs), 50 HIV exposed but seronegative individuals (ESNs) and 260 healthy controls from same ethnic origin were recruited. Genotyping of TNF-α variants (−863C/A, -308G/A and -238G/A) was done using PCR-RFLP. CD4 counts were determined by flow cytometry. Plasma viral load was estimated by COBAS AMPLICOR HIV-1 monitor test. Plasma TNF-α concentration was estimated by Human CBA Th1/Th2 cytokine kit. The lymphocyte mitochondrial membrane potential was measured by JC-1 dye by flow cytometry.ResultsGenotype and allele frequency of TNF-α -238G/A and -863C/A was not significantly different in HIV-1-infected patients when compared to controls, while that of TNF-α -308G/A variant (high TNF-α producer) was significantly higher in FPs compared to SPs (p<0.01, OR = 3.43). Haplotype analyses also showed that carriers of high TNF-α producing haplotype CAG was significantly more common among FPs compared to SPs (p<0.01, OR = 3). The circulating TNF-α levels in blood also correlated well with genotypes. The lymphocyte mitochondrial membrane potential of FPs having CAG haplotype was significantly low as compared to wild type (CGG) haplotype (417±22 vs 571±28, p<0.01).ConclusionHigh producer haplotype, CAG of TNF-α gene associates with enhanced apoptosis of lymphocytes in HIV-1 infected individuals, hence faster progression to AIDS. However, further functional studies are needed to confirm this association and this knowledge may help clinicians to better understand the disease outcome.

Immersion challenge with low and highly virulent infectious salmon anaemia virus reveals different pathogenesis in Atlantic salmon, Salmo salar L.

The salmonid orthomyxovirus infectious salmon anaemia virus (ISAV) causes disease of varying severity in farmed Atlantic salmon, Salmo salar L. Field observations suggest that host factors, the environment and differences between ISAV strains attribute to the large variation in disease progression. Variation in host mortality and dissemination of ISAV isolates with high and low virulence (based on a previously published injection challenge) were investigated using immersion challenge. Virus dissemination was determined using real-time PCR and immunohistochemistry in several organs, including blood. Surprisingly, the low virulent virus (LVI) replicated and produced nucleoprotein at earlier time points post-infection compared to the virus of high virulence (HVI). This was particularly noticeable in the gills as indicated by different viral load profiles. However, the HVI reached a higher maximum viral load in all tested organs and full blood. This was associated with a higher mortality of 100% as compared to 20% in the LVI group by day 23 post-infection. Immersion challenge represented a more natural infection method and suggested that specific entry routes into the fish may be of key importance between ISAV strains. The results suggest that a difference in virulence is important for variations in virus dissemination and pathogenesis (disease development).

Effect of Highly Active Antiretroviral Therapy (HAART) on Human Immunodeficiency Virus Disease Pathogenesis and Progression

Human immunodeficiency virus (HIV), the causative agent of Acquired Immunodeficiency Syndrome (AIDS) was discovered way back in 1983. More than three decades since its discovery, HIV infection diagnosis, treatment and management has been a big challenge to the medical field. HIV infection is attributed to cause compromised T-cell and B-cell immunity, promote different malignancies and the infected individuals are at risk of acquiring other viral, bacterial, fungal and parasitic infections. HIV disease progression was found different in infected population, where few HIV infected patients develop AIDS in less than 5 years and are called as early progressors, HIV infected population in whom development of AIDS is slow and may remain normal up to 10 years are termed as late progressors and patients in whom the symptoms of AIDS are not seen even after 10-15 years are labeled as long term non-progressors. The variability in disease progression is not completely understood. After the discovery of HAART, the mortality of the HIV infected population has significantly reduced but the morbidity attributed to HAART has remained as a serious concern. From being a life threatening infection HIV has now become a chronic infection, where patients live their natural life years with the HAART therapy. Among the most significant changes in HIV infection and pathogenesis is the development of non-infectious complications attributed to the HIV infection, HAART therapy, other demographic factors and co-morbidities. Other factors that influence the disease pathogenesis and progression include chronic immune activation, drug resistance and toxic side effects of HAART therapy. Among this Immune activation plays a key role in the pathogenesis and progression of HIV infection.

Quantitative stratification of diffuse parenchymal lung diseases.

Diffuse parenchymal lung diseases (DPLDs) are characterized by widespread pathological changes within the pulmonary tissue that impair the elasticity and gas exchange properties of the lungs. Clinical-radiological diagnosis of these diseases remains challenging and their clinical course is characterized by variable disease progression. These challenges have hindered the introduction of robust objective biomarkers for patient-specific prediction based on specific phenotypes in clinical practice for patients with DPLD. Therefore, strategies facilitating individualized clinical management, staging and identification of specific phenotypes linked to clinical disease outcomes or therapeutic responses are urgently needed. A classification schema consistently reflecting the radiological, clinical (lung function and clinical outcomes) and pathological features of a disease represents a critical need in modern pulmonary medicine. Herein, we report a quantitative stratification paradigm to identify subsets of DPLD patients with characteristic radiologic patterns in an unsupervised manner and demonstrate significant correlation of these self-organized disease groups with clinically accepted surrogate endpoints. The proposed consistent and reproducible technique could potentially transform diagnostic staging, clinical management and prognostication of DPLD patients as well as facilitate patient selection for clinical trials beyond the ability of current radiological tools. In addition, the sequential quantitative stratification of the type and extent of parenchymal process may allow standardized and objective monitoring of disease, early assessment of treatment response and mortality prediction for DPLD patients.

Primary ciliary dyskinesia: critical evaluation of clinical symptoms and diagnosis in patients with normal and abnormal ultrastructure

BackgroundPrimary ciliary dyskinesia (PCD) is a rare disorder with variable disease progression. To date, mutations in more than 20 different genes have been found. At present, PCD subtypes are described according to the ultrastructural defect on transmission electron microscopy (TEM) of the motile cilia. PCD with normal ultrastructure (NU) is rarely reported because it requires additional testing. Biallelic mutations in DNAH11 have been described as one cause of PCD with NU.The aim of our study was to describe the clinical characteristics of a large population of patients with PCD, in relation to the ultrastructural defect. Additionally, we aimed to demonstrate the need for biopsy and cell culture to reliably diagnose PCD, especially the NU subtype.MethodsWe retrospectively analyzed data from 206 patients with PCD. We compared the clinical characteristics, lung function, microbiology and imaging results of 68 patients with PCD and NU to those of 90 patients with dynein deficiencies and 41 patients with central pair abnormalities. In addition, we aimed to demonstrate the robustness of the diagnosis of the NU subtype in cell culture by data from genetic analysis.ResultsPCD with NU comprised 33% (68/206) of all patients with PCD. Compared to other subtypes, patients with PCD and NU had a similar frequency of upper and lower respiratory tract problems, as well as similar lung function and imaging. With the currently widely applied approach, without cell culture, the diagnosis would have been missed in 16% (11/68) of patients with NU. Genetic analysis was performed in 29/68 patients with PCD and NU, and biallelic mutations were found in 79% (23/29) of tested patients.ConclusionsWe reported on the clinical characteristics of a large population of patients with PCD and NU. We have shown that systematic performance of biopsy and cell culture increases sensitivity to detect PCD, especially the subtype with NU.PCD with NU has similar clinical characteristics as other PCD types and requires biopsy plus ciliogenesis in culture for optimal diagnostic yield.

A Aggressive Osteosarcoma of Mandible with Lung Metastasis in a 5 Year Child: A Case Report

Osteosarcoma is a malignant mesenchymal tumor whose cancerous cells produce osteoid matrix. It is the most common primary malignant bone tumor, accounting for approximately 20% of the sarcomas, but osteosarcoma of mandible is rare only 5% of the osteosarcomas occur in the jaws and occur mainly in adult population in their later part of the life. They present various clinical and histological aspects, as well as variable disease progression and outcome. Mandibular osteosarcoma are slow growing tumors and have better prognosis compared to other site. Lung is the most common site of metastasis in osteosarcoma mainly in the long bones, in craniofascial osteosarcoma lung metastasis is a rare findings. We are presenting a case of osteosarcoma of mandible in 5 year child with aggressive initial presentation.

Sample Size and Cost Analysis for Pulmonary Arterial Hypertension Drug Trials Using Various Imaging Modalities to Assess Right Ventricular Size and Function End Points

Placebo-controlled trials for pulmonary arterial hypertension are no longer acceptable because new therapies must show clinically significant effects on top of standard treatment. The purpose of this study was to estimate sample sizes and imaging costs for the planning of a hypothetical pulmonary arterial hypertension drug trial using imaging to detect changes in right ventricular size and function in response to combined therapy. Same-day cardiovascular MR (CMR) and 2-dimensional (2D) and 3D transthoracic echocardiography (2DTTE and 3DTTE) were performed in 22 patients with pulmonary arterial hypertension (54±13 years of age) twice, 6 months apart. Short-axis CMR cines and full-volume 3DTTE data sets of the right ventricle were used to measure end-diastolic volume and ejection fraction. Fractional area change was obtained from 2DTTE. Sample size calculations used a 2-sample t test model incorporating differences between baseline and 6-month measurements. Cost estimates were made using the Medicare fee schedule. No significant differences were noted between baseline and follow-up measurements. Large SDs reflected variable progression of disease in individual patients on standard therapy and measurement variability. These sources of variability resulted in intertechnique differences in sample sizes: to detect a change of 5% to 15% in 3DTTE-derived right ventricular ejection fraction and fractional area change or change of 15 to 30 mL in 3DTTE right ventricular end-diastolic volume; sample sizes were 2× to 2.5× those required by CMR. As a result, the total cost of a trial using complete TTE was greater than CMR, which was greater than limited TTE. Because of lower measurement variability, CMR is more cost saving in pulmonary arterial hypertension drug trials than echocardiography, unless limited TTE is used.

Spontaneous Variants of the [RNQ+] Prion in Yeast Demonstrate the Extensive Conformational Diversity Possible with Prion Proteins

Prion strains (or variants) are structurally distinct amyloid conformations arising from a single polypeptide sequence. The existence of prion strains has been well documented in mammalian prion diseases. In many cases, prion strains manifest as variation in disease progression and pathology, and in some cases, these prion strains also show distinct biochemical properties. Yet, the underlying basis of prion propagation and the extent of conformational possibilities available to amyloidogenic proteins remain largely undefined. Prion proteins in yeast that are also capable of maintaining multiple self-propagating structures have provided much insight into prion biology. Here, we explore the vast structural diversity of the yeast prion [RNQ+] in Saccharomyces cerevisiae. We screened for the formation of [RNQ+] in vivo, allowing us to calculate the rate of spontaneous formation as ~2.96x10-6, and successfully isolate several different [RNQ+] variants. Through a comprehensive set of biochemical and biological analyses, we show that these prion variants are indeed novel. No individual property or set of properties, including aggregate stability and size, was sufficient to explain the physical basis and range of prion variants and their resulting cellular phenotypes. Furthermore, all of the [RNQ+] variants that we isolated were able to facilitate the de novo formation of the yeast prion [PSI+], an epigenetic determinant of translation termination. This supports the hypothesis that [RNQ+] acts as a functional amyloid in regulating the formation of [PSI+] to produce phenotypic diversity within a yeast population and promote adaptation. Collectively, this work shows the broad spectrum of available amyloid conformations, and thereby expands the foundation for studying the complex factors that interact to regulate the propagation of distinct aggregate structures.

Variants in ZNRD1 Gene Predict HIV-1/AIDS Disease Progression in a Han Chinese Population in Taiwan

Patients demonstrate notable variations in disease progression following human immunodeficiency virus (HIV) infection. We aimed to identify ZNRD1 and RNF39 genetic variants linked to AIDS progression. We conducted a genetic association study in HIV-1-infected Han Chinese patients residing in Taiwan. The clinical characteristics of 143 HIV-1-infected patients were measured, and patients were split into 2 groups: AIDS progression and AIDS non-progression. Genotyping of ZNRD1 and RNF39 was performed in all participants. We found that patients in the AIDS progression group had higher HIV-1 viral loads and lower CD4 cell counts than did patients in the AIDS non-progression group. The frequency of the AA genotype of ZNRD1 (rs16896970) was lower in the AIDS progression group than in the AIDS non-progression group. Patients with AA genotypes had lower levels of HIV-1 viral loads and higher levels of CD4 cell counts than did patients with AG+GG genotypes. AIDS progression in patients with the AA group is significantly different from that in patients with the AG and GG groups by using Kaplan-Meier survival analysis. The hazard ratio for progression was lower in the AA group than in the AG and GG groups. We identified a SNP that contributes to AIDS progression in HIV-1-infected patients in this population. This SNP had a significant protective influence on AIDS progression, and polymorphisms of the ZNRD1 gene may play a role in the pathogenesis of HIV-1 infection.

The Role of the Cerebellum in the Pathophysiology of Parkinson's Disease

Parkinson's disease (PD), the most common neurodegenerative movement disorder, has traditionally been considered a "classic" basal ganglia disease, as the most obvious pathology is seen in the dopaminergic cells in the substantia nigra pars compacta. Nevertheless recent discoveries in anatomical connections linking the basal ganglia and the cerebellum have led to a re-examination of the role of the cerebellum in the pathophysiology of PD. This review summarizes the role of the cerebellum in explaining many curious features of PD: the significant variation in disease progression between individuals; why severity of dopaminergic deficit correlates with many features of PD such as bradykinesia, but not tremor; and why PD subjects with a tremor-predominant presentation tend to have a more benign prognosis. It is clear that the cerebellum participates in compensatory mechanisms associated with the disease and must be considered an essential contributor to the overall pathophysiology of PD.

Cost-Effective Design of Pulmonary Arterial Hypertension Trials To Detect Changes in Right Ventricular Size and Function: 3D Echocardiography Versus Cardiovascular Magnetic Resonance

Purpose Both cardiovascular magnetic resonance (CMR) and 3D transthoracic echocardiography (3DE) can quantify right ventricular (RV) end diastolic volume (EDV) and ejection fraction (EF) accurately. This study was designed to estimate sample sizes and imaging costs to detect changes in RV EDV and EF using 3DE and CMR for future pulmonary arterial hypertension (PAH) drug trials. Methods and Materials Same day CMR and 3DE were performed on 20 PAH patients (age: 53±13 yrs, 19 females) at 0 and 6 months. Consecutive short axis cines spanning the entire RV (Philips 1.5-T scanner) and full-volume acquisitions of the RV (Philips iE33+TomTec 4D RV-Function software) were used to measure EDV and EF. Sample size calculations using two-sample repeated measures to account for changes over time were performed modeling a placebo-controlled trial (Stata v12.1). Cost estimates were made using the 2012 Medicare physician fee schedule. Results No significant differences were noted between 0- and 6-month RV EF and EDV measurements with either CMR or 3DE, but the relatively large SDs reflected variable progression of disease in individual patients on standard therapy. Sample sizes required for 3DE were roughly 3 times greater than CMR. Although the per-study cost of CMR (~$400) is approximately double that of 3DE (~$200), the total cost of a trial using CMR is considerably lower. Conclusions Both CMR and 3DE can be used to detect the effects of new PAH therapies on RV EDV and EF, but CMR is more cost-effective. Population characteristics (average ± SD) Baseline 6 months CMR 3DE CMR 3DE RV EF (%) 34 ± 15 32 ± 12 36 ± 11 33 ± 9 RV EDV (mL) 245 ± 58 195 ± 59 244 ± 71 199 ± 48 Estimated per-group sample sizes (placebo-controlled trial - 90% power) Estimated cost (US$) CMR 3DE CMR 3DE EF: 3% change 54 169 89,000 143,000 EF: 5% change 20 61 33,000 52,000 RVEDV: 20 mL change 44 138 73,000 117,000 RVEDV: 30 mL change 20 61 33,000 52,000

H02 Progress report for the model-HD project (follow-up on EHDN announcement)

Background MODEL-HD is a collaborative effort involving CHDI, FDA and the HD research community to develop a disease progression model for Huntington9s Disease. Disease progression models like the one here envisaged are considered good tools to plan clinical research and to help to simulate clinical trials. Methods/techniques Competing models (based on nonlinear mixed effects and other modelling techniques) are being fit to a combined data set using data from observational studies (REGISTRY, COHORT, PREDICT, TRACK and ENROLL) and selected clinical trials (CARE, Horizon, and others as they become available). These models are being developed by a team of experienced modellers (the MODEL-HD working group) and are under review by an advisory committee made up of HD scientists and clinical experts. Results/outcome We present our current base model for the age at first appearance and rate of progression of selected signs and symptoms of HD as functions of age and CAG length fit to data from REGISTRY, COHORT and other studies (as appropriate). Discussion We will discuss opportunities for future work that will be built upon this base model by attempting to include genetic, environmental, and life-style related variables that explain variability in disease progression and by attempting to characterise the diverse patterns of disease progression that appear in the study populations.

Aberrant innate immune sensing leads to the rapid progression of idiopathic pulmonary fibrosis

Novel approaches are needed to define subgroups of patients with Idiopathic pulmonary fibrosis (IPF) at risk for acute exacerbations and/or accelerated progression of this generally fatal disease. Progression of disease is an integral component of IPF with a median survival of 3 to 5 years. Conversely, a high degree of variability in disease progression has been reported among series. The characteristics of patients at risk of earlier death predominantly rely on baseline HRCT appearance, but this concept that has been challenged. Disparate physiological approaches have also been taken to identify patients at risk of mortality, with varying results. We hypothesized that the rapid decline in lung function in IPF may be a consequence of an abnormal host response to pathogen-associated molecular patterns (PAMPs), leading to aberrant activation in fibroblasts and fibrosis. Analysis of upper and lower lobe surgical lung biopsies (SLBs) indicated that TLR9, a hypomethylated CpG DNA receptor, is prominently expressed at the transcript and protein level, most notably in biopsies from rapidly progressive IPF patients. Surprisingly, fibroblasts appeared to be a major cellular source of TLR9 expression in IPF biopsies from this group of progressors. Further, CpG DNA promoted profibrotic cytokine and chemokine synthesis in isolated human IPF fibroblasts, most markedly again in cells from patients with the rapidly progressive IPF phenotype, in a TLR9-dependent manner. Finally, CpG DNA exacerbated fibrosis in an in vivo model initiated by the adoptive transfer of primary fibroblasts derived from patients who exhibited rapidly progressing fibrosis. Together, these data suggested that TLR9 activation via hypomethylated DNA might be an important mechanism in promoting fibrosis particularly in patients prone to rapidly progressing IPF.

Muscle wasting in animal models of severe illness

Muscle wasting is a serious complication of various clinical conditions that significantly worsens the prognosis of the illnesses. Clinically relevant models of muscle wasting are essential for understanding its pathogenesis and for selective preclinical testing of potential therapeutic agents. The data presented here indicate that muscle wasting has been well characterized in rat models of sepsis (endotoxaemia, and caecal ligation and puncture), in rat models of chronic renal failure (partial nephrectomy), in animal models of intensive care unit patients (corticosteroid treatment combined with peripheral denervation or with administration of neuromuscular blocking drugs) and in murine and rat models of cancer (tumour cell transplantation). There is a need to explore genetically engineered mouse models of cancer. The degree of protein degradation in skeletal muscle is not well characterized in animal models of liver cirrhosis, chronic heart failure and chronic obstructive pulmonary disease. The major difficulties with all models are standardization and high variation in disease progression and a lack of reflection of clinical reality in some of the models. The translation of the information obtained by using these models to clinical practice may be problematic.

Patient specific proteolytic activity of monocyte-derived macrophages and osteoclasts predicted with temporal kinase activation states during differentiation

Patient-to-patient variability in disease progression continues to complicate clinical decisions of treatment regimens for cardiovascular diseases, metastatic cancers and osteoporosis. Here, we investigated if monocytes, circulating white blood cells that enter tissues and contribute to disease progression by differentiating into macrophages or osteoclasts, could be useful in understanding this variability. Monocyte-derived macrophages and osteoclasts produce cysteine cathepsins, powerful extracellular matrix proteases which have been mechanistically linked to accelerated atherosclerotic, osteoporotic, and tumor progression. We hypothesized that multivariate analysis of temporal kinase activation states during monocyte differentiation could predict cathepsin proteolytic responses of monocyte-derived macrophages and osteoclasts in a patient-specific manner. Freshly isolated primary monocytes were differentiated with M-CSF or RANKL into macrophages or osteoclasts, respectively, and phosphorylation of ERK1/2, Akt, p38 MAPK, JNK, c-jun, and IκB-α were measured at days 1, 3, 6, and 9. In parallel, cell diameters and numbers of nuclei were measured, and multiplex cathepsin zymography was used to quantify cathepsins K, L, S, and V activity from cell extracts and conditioned media. There was extensive patient-to-patient variability in temporal kinase activation states, cell morphologies, and cathepsin K, L, S, and V proteolytic activity. Partial least squares regression models trained with temporal kinase activation states successfully predicted patient-specific morphological characteristics (mean cell diameter and number of nuclei) and patient-specific cathepsin proteolytic activity with predictability as high as 95%, even with the challenge of incorporating the complex, unknown cues from individual patients' unique genetic and biochemical backgrounds. This personalized medicine approach considers patient variability in kinase signals to predict cathepsin activity. Such analyses may provide beneficial tools for personalized kinase and protease inhibitor therapies for tissue destructive diseases.

Variable disease progression after successful stem cell transplantation: Prospective follow‐up investigations in eight patients with Hurler syndrome

We report the results of a prospective, standardized follow-up programme of eight children (median age at SCT 1.2 yr) with mucopolysaccharidosis (MPS1H, M. Hurler) transplanted using a fludarabine-based SCT. SCT resulted in stable engraftment without transplant-related mortality. All patients are alive, engrafted and in ambulatory care. During follow-up (median five yr, 1.9-8 yr), six of eight showed developmental delay (two severe, two mild/no), all eight had spinal deformities and one received hip surgery for acetabular dysplasia. Hand surgery for carpal tunnel release and trigger digits was required in five of the patients. The cranio-cervical junction was narrowed in four patients, one child having already received surgery. CC was present in all patients prior to SCT. It remained unchanged in seven and regressed in one child. Severe cardiac dysfunction was present in two of the eight children before SCT. Cardiac pump function was normal in six patients and ameliorated in two, while valve abnormalities could be detected in six patients. Currently, transplantation seems no longer the major obstacle for MPS1H patients, but the variable musculoskeletal disease progression after successful SCT remains a challenge. Patients with Hurler syndrome need specialized follow-up care because of their manifold health problems. The standardized follow-up presented here is a step to optimize care for MPS children and their families after SCT.