Defect-free graphene enhances enzyme delivery to fibroblasts derived from patients with lysosomal storage disorders

Enzyme replacement therapy shows remarkable clinical improvement in treating lysosomal storage disorders. However, this therapeutic approach is hampered by limitations in the delivery of the enzyme to cells and tissues. Therefore, there is an urgent, unmet clinical need to develop new strategies to enhance the enzyme delivery to diseased cells. Graphene-based materials, due to their dimensionality and favourable pattern of interaction with cells, represent a promising platform for the loading and delivery of therapeutic cargo. Herein, the potential use of graphene-based materials, including defect-free graphene with positive or negative surface charge and graphene oxide with different lateral dimensions, was investigated for the delivery of lysosomal enzymes in fibroblasts derived from patients with Mucopolysaccharidosis VI and Pompe disease. We report excellent biocompatibility of all graphene-based materials up to a concentration of 100 μg mL^-1 in the cell lines studied. In addition, a noticeable difference in the uptake profile of the materials was observed. Neither type of graphene oxide was taken up by the cells to a significant extent. In contrast, the two types of graphene were efficiently taken up, localizing in the lysosomes. Furthermore, we demonstrate that cationic graphene flakes can be used as carriers for arylsulfatase B enzyme, for the delivery of the lacking enzyme to the lysosomes of Mucopolysaccharidosis VI fibroblasts. Arylsulfatase B complexed with cationic graphene flakes not only retained the enzymatic activity, but also exerted biological effects almost twice as high as arylsulfatase B alone in the clearance of the substrate in Mucopolysaccharidosis VI fibroblasts. This study lays the groundwork for the potential use of graphene-based materials as carriers for enzyme replacement therapy in lysosomal storage disorders.

Enzyme replacement therapy and hematopoietic stem cell transplant: a new paradigm of treatment in Wolman disease

BACKGROUND

Wolman disease is a rare, lysosomal storage disorder in which biallelic variants in the LIPA gene result in reduced or complete lack of lysosomal acid lipase. The accumulation of the substrates; cholesterol esters and triglycerides, significantly impacts cellular function. Untreated patients die within the first 12 months of life. Clinically, patients present severely malnourished, with diarrhoea and hepatosplenomegaly, many have an inflammatory phenotype, including with hemophagocytic lymphohistiocytosis (HLH). Hematopoietic stem cell transplant (HCT) had been historically the only treatment available but has a high procedure-related mortality because of disease progression and disease-associated morbidities. More recently, enzyme replacement therapy (ERT) with dietary substrate reduction (DSR) has significantly improved patient survival. However, ERT is life long, expensive and its utility is limited by anti-drug antibodies (ADA) and the need for central venous access.

RESULTS

We describe five Wolman disease patients diagnosed in infancy that were treated at Royal Manchester Children's Hospital receiving ERT with DSR then HCT-multimodal therapy. In 3/5 an initial response to ERT was attenuated by ADA with associated clinical and laboratory features of deterioration. 1/5 developed anaphylaxis to ERT and the other patient died post HCT with ongoing HLH. All patients received allogeneic HCT. 4/5 patients are alive, and both disease phenotype and laboratory parameters are improved compared to when they were on ERT alone. The gastrointestinal symptoms are particularly improved after HCT, with reduced diarrhoea and vomiting. This allows gradual structured normalisation of diet with improved tolerance of dietary fat. Histologically there are reduced cholesterol clefts, fewer foamy macrophages and an improved villous structure. Disease biomarkers also show improvement with ERT, immunotherapy and HCT. Three patients have mixed chimerism after HCT, indicating a likely engraftment-defect in this condition.

CONCLUSION

We describe combined ERT, DSR and HCT, multimodal treatment for Wolman disease. ERT and DSR stabilises the sick infant and reduces the formerly described prohibitively high, transplant-associated mortality in this condition. HCT abrogates the problems of ERT, namely attenuating ADA, the need for continuing venous access, and continuing high cost drug treatment. HCT also brings improved efficacy, particularly evident in improved gastrointestinal function and histology. Multimodal therapy should be considered a new paradigm of treatment for Wolman disease patients where there is an attenuated response to ERT, and for all patients where there is a well-matched transplant donor, in order to improve long term gut function, tolerance of a normal diet and quality of life.

2019 UK National Guideline for consultations requiring sexual history taking : Clinical Effectiveness Group British Association for Sexual Health and HIV

This guideline is an update of a previous version published in 2013. In this new version, we have reflected changes in the way sexual health services are now provided by assuming an integrated Sexual Health/Sexual and Reproductive Healthcare service. There are new recommendations for online testing, female genital mutilation (FGM), chemsex and considerations for transgender (and non-binary) individuals. Previous versions rather assumed a cis-gender clientele and so we have taken a more mechanistic approach to sex and risk without assuming gender identification. We have updated our gender terminology in line with the British Association for Sexual Health and HIV 'sexual health standards for trans, including non-binary, people' although have retained the terminology of 'men' and 'women' in a few cases where it related to other guidelines, e.g. human papillomavirus vaccination and FGM.

The effect of haemopoietic stem cell transplantation on the ocular phenotype in mucopolysaccharidosis type I (Hurler)

PURPOSE

To determine whether the ocular phenotype in patients with mucopolysaccharidosis type I (MPSI) Hurler is affected by the efficacy of previous haemopoietic stem cell transplantation (HSCT).

DESIGN

A retrospective cohort study of patients with MPSI who had undergone treatment with HSCT.

METHODS

Ocular phenotype was documented for each patient and compared to levels of biomarkers representing efficacy of previous transplantation.

MAIN OUTCOME MEASURES

Assessment of visual acuity (VA), severity of corneal clouding and the presence of optic neuropathy or retinopathy. Biomarker assessment included dermatan sulphate/chondroitin sulphate (DS/CS) ratio and iduronidase enzyme level.

RESULTS

Severe corneal clouding was significantly greater in patients with lower iduronidase levels (p = 0.023) and raised DS/CS ratio (R²  = 0.28 p = 0.043). Better VA was related to a higher iduronidase levels (R²  = 0.15, p = 0.004) and lower DS/CS ratio (R²  = 0.38, p = 0.001).

CONCLUSION

Improved ocular phenotypes in MPSI are associated with markers signifying efficacy of prior transplant. Early and effective HSCT may result in a better visual prognosis and reduction in ocular complications for patients with MPSI.

IDUA mutational profile and genotype-phenotype relationships in UK patients with Mucopolysaccharidosis Type I

Mucopolysaccharidosis Type I (MPS I) is a lysosomal storage disorder with varying degrees of phenotypic severity caused by mutations in IDUA. Over 200 disease-causing variants in IDUA have been reported. We describe the profile of disease-causing variants in 291 individuals with MPS I for whom IDUA sequencing was performed, focusing on the UK subset of the cohort. A total of 63 variants were identified, of which 20 were novel, and the functional significance of the novel variants is explored. The severe form of MPS I is treated with hematopoietic stem cell transplantation, known to have improved outcomes with earlier age at treatment. Developing genotype-phenotype relationships would therefore have considerable clinical utility, especially in the light of the development of newborn screening programs for MPS I. Associations between genotype and phenotype are examined in this cohort, particularly in the context of the profile of variants identified in UK individuals. Relevant associations can be made for the majority of UK individuals based on the presence of nonsense or truncating variants as well as other associations described in this report.

Reducing the risk of mouth-to-mouth transmission of pathogens via re-usable, machine-read parking tickets: an observational cohort study

The car parks at the study hospital are accessed using re-usable, machine-read tickets. In the initial phase of this study, 598 staff members were observed entering the car park, and 21.6% of them put their parking ticket in their mouth. Ultraviolet dye was used to demonstrate card-to-card cross-contamination. Swabs of the ticket machine yielded commensal bacteria: coagulase-negative staphylococci and a Bacillus sp. After placing a poster on the ticket-reading machine highlighting the potential risk of infection, a further 1366 observations demonstrated a significant and persistent decline in the proportion of staff who put their ticket in their mouth (P<0.001).

Long term survival and cardiopulmonary outcome in children with Hurler syndrome after haematopoietic stem cell transplantation

Premature death in untreated children with Hurler syndrome (HS) in the first decade of life is largely due to life-threatening cardiopulmonary complications. We examined the long-term survival and cardiopulmonary outcome in 54 children undergoing haematopoietic stem cell transplantation (HSCT) at the Royal Manchester Children's Hospital from 1985 to 2008. The median age at first HSCT was 15.1 months. Eighteen had graft failure and nine died after first HSCT. Of 18 patients with graft failure, 17 underwent second HSCT and the remaining one was lost to follow-up (LOF). Twelve were alive-and-engrafted after second HSCT. The overall survival at one year and 20-years was the same at 73.7%. Six children were followed up at the referral centers and excluded from cardiopulmonary endpoint review. Of the 33 evaluable children for the cardiopulmonary endpoints, nine (27.3%) had normal cardiac assessment. Of the four children on angiotensin-converting-enzyme inhibitors, two had mild cardiomyopathy and two had aortic valvular replacement. Twenty (60%) had mild/moderate mitral and/or aortic insufficiencies. Two had overnight hypoxia needing nocturnal non-invasive support. Enzyme level and donor chimerism are important predictors of long-term cardiac outcome.

Newborn screening for mucopolysaccharidoses: a pilot study of measurement of glycosaminoglycans by tandem mass spectrometry

BACKGROUND

Mucopolysaccharidoses (MPS) are a group of inborn errors of metabolism that are progressive and usually result in irreversible skeletal, visceral, and/or brain damage, highlighting a need for early diagnosis.

METHODS

This pilot study analyzed 2862 dried blood spots (DBS) from newborns and 14 DBS from newborn patients with MPS (MPS I, n = 7; MPS II, n = 2; MPS III, n = 5). Disaccharides were produced from polymer GAGs by digestion with chondroitinase B, heparitinase, and keratanase II. Heparan sulfate (0S, NS), dermatan sulfate (DS) and mono- and di-sulfated KS were measured by liquid chromatography tandem mass spectrometry (LC-MS/MS). Median absolute deviation (MAD) was used to determine cutoffs to distinguish patients from controls. Cutoffs were defined as median + 7× MAD from general newborns.

RESULTS

The cutoffs were as follows: HS-0S > 90 ng/mL; HS-NS > 23 ng/mL, DS > 88 ng/mL; mono-sulfated KS > 445 ng/mL; di-sulfated KS > 89 ng/mL and ratio di-KS in total KS > 32 %. All MPS I and II samples were above the cutoffs for HS-0S, HS-NS, and DS, and all MPS III samples were above cutoffs for HS-0S and HS-NS. The rate of false positives for MPS I and II was 0.03 % based on a combination of HS-0S, HS-NS, and DS, and for MPS III was 0.9 % based upon a combination of HS-0S and HS-NS.

CONCLUSIONS

Combination of levels of two or more different GAGs improves separation of MPS patients from unaffected controls, indicating that GAG measurements are potentially valuable biomarkers for newborn screening for MPS.

Attenuated mucopolysaccharidosis type VI (Maroteaux-Lamy syndrome) due to homozygosity for the p.Y210C mutation in the ARSB gene

We describe the case of a boy recently diagnosed with an attenuated form of mucopolysacchararidosis VI (MPS VI, Maroteaux-Lamy syndrome). The Y210C mutation has not been described previously in the homozygous state, although this is a common ARSB mutation. His phenotype is essentially musculoskeletal. Urine screening tests based on measuring total GAG may miss this presentation as total GAGs were not elevated in the patient (although the electrophoresis pattern was clearly abnormal). In this phenotype the benefit of ERT remains to be established.

The craniocervical junction following successful haematopoietic stem cell transplantation for mucopolysaccharidosis type I H (Hurler syndrome)

Mucopolysaccharidosis I Hurler (MPS IH) is a progressive multisystemic disorder caused by alpha-L-iduronidase deficiency. First choice of treatment in MPS IH children is haematopoietic stem cell transplantation (HSCT). The effect of HSCT has been shown to have limited influence on skeletal manifestations by poor penetration of musculoskeletal tissues by the enzyme derived from donor leucocytes. Aim of this study was to investigate the effect of HSCT on the craniocervical junction (CCJ) in Hurler patients. We analysed retrospectively sequential magnetic resonance imaging (MRI) scans of 30 patients with Hurler disease treated by HSCT since 1982 at the Royal Manchester Children's Hospital, UK, in order to determine whether the patients suffer from dens hypoplasia. Results were compared with biochemical and clinical characteristics: Enzyme activity (EA), chimerism, urinary glycosaminoglycan (GAG) excretion and neurological status. Investigations were part of standard clinical procedures. Results are descriptive in presentation. In 26/30 patients a determination of odontoid hypoplasia was feasible. The majority showed a normal dens length and an increase with age. Only 3/26 revealed a dens hypoplasia. One of them had only partial donor engraftment (DE) with reduced EA, one of them suffered from chronic graft versus host disease (GVHD). One patient with only partial DE and reduced EA presented with initial dens hypoplasia until preadolescence but normalized later on. There may be a trend towards lower EA and the occurrence of DH in transplanted MPS patients - perhaps the dosage of enzyme plays a role in the correction of skeletal complications in this patient group. HSCT patients with incomplete DE and therefore lower EAs may require special attention and care.

Heparin cofactor II-thrombin complex and dermatan sulphate:chondroitin sulphate ratio are biomarkers of short- and long-term treatment effects in mucopolysaccharide diseases

Early detection of mucopolysaccharidosis (MPS) is an important factor in treatment success; therefore, good disease biomarkers are vital. We evaluate heparin cofactor II-thrombin complex (HCII-T) as a biomarker in serum and dried blood spots (DBS) of MPS patients. Serum HCII-T and urine dermatan sulphate:chondroitin sulphate (DS:CS) ratio are also compared longitudinally against clinical outcomes in MPSI, II and VI patients following treatment. Samples were collected from MPS patients at the Royal Manchester Children's Hospital. DS:CS ratio was obtained by measuring the area density of spots from 2D electrophoresis of urinary glycosaminoglycans. Serum and DBS HCII-T was measured by sandwich ELISA. Serum HCII-T is elevated approximately 25-fold in MPS diseases that store DS, clearly distinguishing untreated MPSI, II and VI patients from unaffected age-matched controls. Serum HCII-T is also elevated in MPSIII, which leads to storage of heparan sulphate, with an increase of approximately 4-fold over unaffected age-matched controls. Urine DS:CS ratio and serum HCII-T decrease in response to treatment of MPSI, II and VI patients. HCII-T appears to respond rapidly to perturbations in treatment, whilst DS:CS ratio responds more slowly. HCII-T is a suitable biomarker for MPSI, II and VI, and it may also be informative for MPS diseases storing HS alone, such as MPSIII, although the elevation observed is smaller. In treated MPS patients, HCII-T and DS:CS ratio appear to measure short-term and long-term treatment outcomes, respectively. The potential value of HCII-T measurement in DBS for newborn screening of MPS diseases warrants further investigation.

Biochemical monitoring after haemopoietic stem cell transplant for Hurler syndrome (MPSIH): implications for functional outcome after transplant in metabolic disease

Hurler Syndrome is corrected by allogeneic BMT by the action of donor enzyme on recipient tissue. In this paper, we describe monitoring of 39 patients transplanted in two centres to determine donor chimerism, enzyme level and residual substrate - expressed as dermatan sulphate to chondroitin sulphate ratio. We show that in fully engrafted recipients, the enzyme level, expressed as mumol/g total protein/h, post-transplant is 24.2 from an unrelated donor and 10.2 from a heterozygote family donor (P<0.0001). There is a tight relationship between mean post-transplant enzyme level and residual substrate - Spearman's rank correlation coefficient (Rho) was -0.76 and -0.80 at 12 and 24 months, respectively (P<0.0001). We propose that these differences affect patient outcome. As unrelated donor transplant outcomes improve and especially given the higher levels of donor cell engraftment following cord transplants, our data might influence donor selection where only heterozygote-matched family members are available.

Niemann-Pick disease type C in adults

Although it is often perceived as a paediatric disorder, significant numbers of patients with Niemann-Pick disease type C present for the first time in adult life or survive into adult life. The presentation in these patients differs from that seen in the classical juvenile form of the disease. Adult patients are often referred to clinicians with psychosis or other major psychiatric problems. The dystonia with preserved intellectual functioning can be mistaken for other basal ganglia disorders such as Wilson disease. The presence of vertical gaze palsy is an important clinical clue and, in the presence of a modest increase in plasma chitotriosidase activity, can be very helpful in the differential diagnosis. The diagnosis should be confirmed in suspected cases by filipin staining of cultured fibroblasts, as well as cholesterol esterification studies and DNA mutation analysis.

Thyroid function tests in elderly patients with and without an acute illness

Thyroid function was assessed by measurement of free thyroid hormones and thyrotrophin (TSH) in 78 acutely ill elderly patients and in a control group without acute illness. Abnormal results with any test were more frequently found in the acutely ill group than in controls. In particular, abnormal TSH values were found in 40% of the acutely ill group and in only 8% of controls (p less than 0.001). Seven acutely ill subjects had very low TSH levels (less than 0.04 mU/l) and a blunted response to thyroid-releasing hormone (TRH). With few exceptions these abnormalities could not be attributed to thyroid disease. This suggests that pituitary TSH secretion can be impaired in euthyroid sick old people. High sensitivity TSH assays may therefore be inappropriate as first-line tests of thyroid function, at least in this select group.

The relationship between the dose of dentogingival plaque and the in vitro lymphoproliferative response in subjects with periodontal disease

The in vitro lymphoblastic response to autologous dentogingival plaque (DGP) extract at nine concentrations was measured in 28 individuals (Periodontal Index [Russell 1956] 0.8-7.4). Significantly elevated responses were obtained in 25 of the patients but the levels of the peak responses were unrelated to the severity of the diseases. There was a significant (n = 28, r = -.734) negative linear relationship between the PI of the individuals studied and the logarithmic concentration of DGP producing the peak lymphoblastic response. Lower concentrations of DGP extract would appear to be required to achieve peak responses in patients with severe periodontal disease.