An additive manufacturing-based 3D printed poly ɛ-caprolactone/alginate sulfate/extracellular matrix construct for nasal cartilage regeneration

Various composite scaffolds with different fabrication techniques have been applied in cartilage tissue engineering. In this study, poly ɛ-caprolactone (PCL) was printed by fused deposition modeling method, and the prepared scaffold was filled with Alginate (Alg): Alginate-Sulfate (Alg-Sul) hydrogel to provide a better biomimetic environment and emulate the structure of glycosaminoglycans properly. Furthermore, to enhance chondrogenesis, different concentrations of decellularized extracellular matrix (dECM) were added to the hydrogel. For cellular analyses, the adipose-derived mesenchymal stem cells were seeded on the hydrogel and the results of MTT assay, live/dead staining, and SEM images revealed that the scaffold with 1% dECM had better viscosity, cell viability, and proliferation. The study was conducted on the optimized scaffold (1% dECM) to determine mechanical characteristics, chondrogenic differentiation, and results demonstrated that the scaffold showed mechanical similarity to the native nasal cartilage tissue along with possessing appropriate biochemical features, which makes this new formulation based on PCL/dECM/Alg:Alg-Sul a promising candidate for further in-vivo studies.

Will Tissue-Engineering Strategies Bring New Hope for the Reconstruction of Nasal Septal Cartilage?

The nasal septal cartilage plays an important role in the growth of midface and as a vertical strut preventing the collapse of the nasal bones. The repair of nasal cartilage defects remains a major challenge in reconstructive surgery. The tissue engineering strategy in the development of tissue has opened a new perspective to generate functional tissue for transplantation. Given the poor regenerative properties of cartilage and a limited amount of autologous cartilage availability, intense interest has evoked for tissue engineering approaches for cartilage development to provide better outcomes for patients who require nasal septal reconstruction. Despite numerous attempts to substitute the shapely hyaline cartilage in the nasal cartilages, many significant challenges remained unanswered. The aim of this research was to carry out a critical review of the literature on research work carried out on the development of septal cartilage using a tissue engineering approach, concerning different cell sources, scaffolds and growth factors, as well as its clinical pathway and trials have already been carried out.

Dual functional construct containing kartogenin releasing microtissues and curcumin for cartilage regeneration

BACKGROUND

Regeneration of articular cartilage poses a tremendous challenge due to its limited self-repair capability and inflammation at the damaged site. To generate the desired structures that mimic the structure of native tissue, microtissues with repeated functional units such as cell aggregates have been developed. Multicellular aggregates of mesenchymal stem cells (MSCs) can be used as microscale building blocks of cartilage due to their potential for cell-cell contact, cell proliferation, and differentiation.

METHODS

Chondrogenic microtissues were developed through incorporation of kartogenin-releasing poly (lactic-co-glycolic acid) (PLGA) microparticles (KGN-MP) within the MSC aggregates. The chondrogenic potential of KGN-MP treated MSC aggregates was proven in vitro by studying the chondrogenic markers at the RNA level and histological analysis. In order to address the inflammatory responses at the defect site, the microtissues were delivered in vivo via an injectable, anti-inflammatory hydrogel that contained gelatin methacryloyl (GelMA) loaded with curcumin (Cur).

RESULTS

The KGN-MPs were fabricated to support MSCs during cartilage differentiation. According to real-time RT-PCR analysis, the presence of KGN in the aggregates led to the expression of cartilage markers by the MSCs. Both toluidine blue (TB) and safranin O (SO) staining demonstrated homogeneous glycosaminoglycan production throughout the KGN-MP incorporated MSC aggregates. The curcumin treatment efficiently reduced the expressions of hypertrophy markers by MSCs in vitro. The in vivo results showed that implantation of chondrogenic microtissues (KGN-MP incorporated MSC aggregates) using the curcumin loaded GelMA hydrogel resulted in cartilage tissue regeneration that had characteristic features close to the natural hyaline cartilage according to observational and histological results.

CONCLUSIONS

The use of this novel construct that contained chondrogenic cell blocks and curcumin is highly desired for cartilage regeneration.

Cerebrospinal fluid biomarkers for predicting development of multiple sclerosis in acute optic neuritis: a population-based prospective cohort study

Background

Long-term outcome in multiple sclerosis (MS) depends on early treatment. In patients with acute optic neuritis (ON), an early inflammatory event, we investigated markers in cerebrospinal fluid (CSF), which may predict a diagnosis of MS.

Methods

Forty patients with acute ON were recruited in a prospective population-based cohort with median 29 months (range 19–41) of follow-up. Paired CSF and serum samples were taken within 14 days (range 2–38), prior to treatment. Prospectively, 16/40 patients were by a uniform algorithm diagnosed with MS (MS-ON) and 24 patients continued to manifest isolated ON (ION) during follow-up. Levels of cytokines and neurofilament light chain (NF-L) were measured at the onset of acute ON and compared to healthy controls (HC). Significance levels were corrected for multiple comparisons (“q”). The predictive value of biomarkers was determined with multivariable prediction models using nomograms.

Results

CSF TNF-α, IL-10, and CXCL13 levels were increased in MS-ON compared to those in ION patients (q = 0.021, 0.004, and 0.0006, respectively). MS-ON patients had increased CSF pleocytosis, IgG indices, and oligoclonal bands (OCBs) compared to ION (q = 0.0007, q = 0.0058, and q = 0.0021, respectively). CSF levels of IL-10, TNF-a, IL-17A, and CXCL13 in MS-ON patients correlated with leukocyte counts (r > 0.69 and p < 0.002) and IgG index (r > 0.55, p < 0.037). CSF NF-L levels were increased in ON patients compared to those in HC (q = 0.0077). In MS-ON, a progressive increase in NF-L levels was observed at 7 to 14 days after disease onset (r = 0.73, p < 0.0065). Receiver-operating characteristic (ROC) curves for two multivariable prediction models were generated, with IL-10, CXCL13, and NF-L in one (“candidate”) and IgG index, OCB, and leukocytes in another (“routine”). Area under the curve was 0.89 [95% CI 0.77–1] and 0.86 [0.74–0.98], respectively. Predictions of the risk of MS diagnosis were illustrated by two nomograms.

Conclusions

CSF TNF-α, IL-10, CXCL13, and NF-L levels were associated with the development of MS, suggesting that the inflammatory and neurodegenerative processes occurred early. Based on subsequent diagnosis, we observed a high predictive value of routine and candidate biomarkers in CSF for the development of MS in acute ON. The nomogram predictions may be useful in the diagnostic work-up of MS.

Electronic supplementary material

The online version of this article (10.1186/s12974-019-1440-5) contains supplementary material, which is available to authorized users.

Long-term tolerability, safety and efficacy of rituximab in neuromyelitis optica spectrum disorder: a prospective study

BACKGROUND

Neuromyelitis optica spectrum disorder (NMOSD) is a B-cell-mediated disease with autoimmunity towards the astrocyte water channel aquaporin-4 (AQP-4) in the central nervous system.

OBJECTIVE

To assess the long-term safety and efficacy in NMOSD patients receiving maintenance therapy with B-cell-depleting agent rituximab for more than 2 years.

METHOD

NMOSD patients were included prospectively from 2014 to 2018 and received continuous cycles of rituximab infusions biannually. Incidence of adverse events (AE), serious AEs (SAE), and infusion-related AEs were evaluated through monthly phone calls and neurological examination every 4 months.

RESULTS

A total of 44 NMOSD patients were included, of those 30 were treatment naive (68%). The mean age was 37.2 years with 79.5% females. With overall observation period of 31.6 ± 7.3 months (24-48 months), tolerability was assessed as satisfactory in most cases. We observed infusion reactions (mostly mild) in 31.8% of patients and 31.8% never experienced any AEs after a mean 5.1 cycles of rituximab therapy. Rituximab was also beneficial in terms of improvement in relapse rate (from 0.26 ± 0.54 to 0, P = 0.003) and Expanded Disability Status Scale (from 4.1 ± 1.8 to 3.1 ± 1.8, P < 0.001). Stratification according to AQP4-IgG serostatus showed no difference between groups.

CONCLUSION

Rituximab treatment is well tolerated, safe, and efficacious with a minor risk of mild infusion reactions for NMOSD patients.

MOG encephalomyelitis: international recommendations on diagnosis and antibody testing

Over the past few years, new-generation cell-based assays have demonstrated a robust association of autoantibodies to full-length human myelin oligodendrocyte glycoprotein (MOG-IgG) with (mostly recurrent) optic neuritis, myelitis and brainstem encephalitis, as well as with acute disseminated encephalomyelitis (ADEM)-like presentations. Most experts now consider MOG-IgG-associated encephalomyelitis (MOG-EM) a disease entity in its own right, immunopathogenetically distinct from both classic multiple sclerosis (MS) and aquaporin-4 (AQP4)-IgG-positive neuromyelitis optica spectrum disorders (NMOSD). Owing to a substantial overlap in clinicoradiological presentation, MOG-EM was often unwittingly misdiagnosed as MS in the past. Accordingly, increasing numbers of patients with suspected or established MS are currently being tested for MOG-IgG. However, screening of large unselected cohorts for rare biomarkers can significantly reduce the positive predictive value of a test. To lessen the hazard of overdiagnosing MOG-EM, which may lead to inappropriate treatment, more selective criteria for MOG-IgG testing are urgently needed. In this paper, we propose indications for MOG-IgG testing based on expert consensus. In addition, we give a list of conditions atypical for MOG-EM ("red flags") that should prompt physicians to challenge a positive MOG-IgG test result. Finally, we provide recommendations regarding assay methodology, specimen sampling and data interpretation.

Magnetic resonance imaging findings at the first episode of acute optic neuritis

BACKGROUND

Optic neuritis (ON) is a focal demyelinating event, which may evolve into multiple sclerosis (MS).

OBJECTIVE

To study MRI characteristics in the acute phase of the first ON episode.

METHODS

A prospective population-based study was performed on 31 patients with a first episode of acute ON with a one year follow-up. MRI, clinical evaluation, and detection of aquaporin-4 (AQP4)-IgG and myelin oligodendrocyte glycoprotein (MOG)-IgG was undertaken. For lesion characterization on MRI the optic nerves were divided into three segments: intra-orbital (IO), canalicular (CAN) and chiasmal (CHI).

RESULTS

Lesions of the optic nerve were observed in 80.6%(25/31), with IO location in 48%(12/25), CAN in 8% (2/25) and both IO and CAN in 44%(11/25). Patients who converted to MS had lesions located at IO in 77%(10/13), whereas the group with isolated ON had IO and CAN in 73% (8/11), p = 0.003. Brain lesions were observed in 84% (21/25) at onset of ON; 62%(13/25) progressed to MS with more frequent location in brainstem (p = 0.030) and lesions in periventricular areas (p = 0.015). Spinal cord lesions were detected only in patients who progressed to MS (p = 0.002). MOG-IgG was detected in one patient with an optic nerve lesion located at IO and CAN. Serum AQP4-IgG was detected in none. Follow-up MRI showed progression in optic nerve lesions in 55% (11/20) patients.

CONCLUSIONS

Specific location of optic nerve and brain lesions and the presence of spinal cord lesions in the acute phase of the first ON episode facilitated an MS diagnosis. The extension of optic nerve lesions following ON suggests a long-term progressive degeneration as an important element of ON pathology.

A population-based prospective study of optic neuritis

BACKGROUND

Optic neuritis (ON) is often associated with multiple sclerosis (MS). Early diagnosis is critical to optimal patient management.

OBJECTIVE

To estimate the incidence of acute ON and the rates of conversion to MS and antibody-mediated ON.

METHOD

Population-based prospective study was performed in patients with ON from three ophthalmological departments and 44 practicing ophthalmologists from 2014 to 2016. Ophthalmological and neurological examination, magnetic resonance imaging (MRI), determination of aquaporin-4(AQP4)-IgG and myelin-oligodendrocyte glycoprotein (MOG)-IgG were investigated blindly.

RESULTS

In all, 63 patients were evaluated and 51 fulfilled the criteria for ON. All were Caucasian, with female:male ratio of 2.2:1 and a median age of 38 years (16-66); 44 (86%) had a single episode of ON (four bilateral), while 7/51 (14%) had recurrent ON. The overall age-specific incidence was 3.28 (2.44-4.31) per 100,000 person years, 2.02 for men and 4.57 for women. At follow-up, 20 patients met the diagnostic criteria for MS, MRI lesions disseminated in space and time in 17/20 patients. AQP4-IgG was detected in none, MOG-IgG was detected in two patients.

CONCLUSION

The prospective incidence of ON was estimated. MRI enabled a diagnosis of MS in a subgroup of patients. Antibody-mediated ON with specificity for MOG was detected in 4% of cases.

Demographic and clinical features of neuromyelitis optica: A review

The comparative clinical and demographic features of neuromyelitis optica (NMO) are not well known. In this review we analyzed peer-reviewed publications for incidence and prevalence, clinical phenotypes, and demographic features of NMO. Population-based studies from Europe, South East and Southern Asia, the Caribbean, and Cuba suggest that the incidence and prevalence of NMO ranges from 0.05-0.4 and 0.52-4.4 per 100,000, respectively. Mean age at onset (32.6-45.7) and median time to first relapse (8-12 months) was similar. Most studies reported an excess of disease in women and a relapsing course, particularly in anti-aquaporin 4 antibody (anti AQP4-IgG)-positive patients. Ethnicity may have a bearing on disease phenotype and clinical outcome. Despite limitations inherent to the review process, themes noted in clinical and demographic features of NMO among different populations promote a more global understanding of NMO and strategies to address it.

Neuromyelitis optica and multiple sclerosis: Seeing differences through optical coherence tomography

Neuromyelitis optica (NMO) is an inflammatory autoimmune disease of the central nervous system that preferentially targets the optic nerves and spinal cord. The clinical presentation may suggest multiple sclerosis (MS), but a highly specific serum autoantibody against the astrocytic water channel aquaporin-4 present in up to 80% of NMO patients enables distinction from MS. Optic neuritis may occur in either condition resulting in neuro-anatomical retinal changes. Optical coherence tomography (OCT) has become a useful tool for analyzing retinal damage both in MS and NMO. Numerous studies showed that optic neuritis in NMO typically results in more severe retinal nerve fiber layer (RNFL) and ganglion cell layer thinning and more frequent development of microcystic macular edema than in MS. Furthermore, while patients’ RNFL thinning also occurs in the absence of optic neuritis in MS, subclinical damage seems to be rare in NMO. Thus, OCT might be useful in differentiating NMO from MS and serve as an outcome parameter in clinical studies.

Two clustered cases of confirmed influenza A(H5N1) virus infection, Cambodia, 2011

In February 2011, a mother and her child from Banteay Meanchey Province, Cambodia, were diagnosed, postmortem, with avian influenza A(H5N1) virus infection. A field investigation was conducted by teams from the Cambodian Ministry of Health, the World Health Organization and the Institut Pasteur in Cambodia. Nasopharyngeal, throat and serum specimens collected from 11 household or three neighbour contacts including two suspect cases tested negative by reverse transcriptase-polymerase chain reaction (RT-PCR) for A(H5N1). Follow-up sera from the 11 household contacts also tested negative for A(H5N1) antibodies. Twenty-six HCW who were exposed to the cases without taking adequate personal protective measures self-monitored and none developed symptoms within the two following weeks. An unknown number of passengers travelling with the cases on a minibus while they were symptomatic could not be traced but no clusters of severe respiratory illnesses were detected through the Cambodian surveillance systems in the two weeks after that. The likely cause of the fatal infection in the mother and the child was common-source exposure in Preah Sdach District, Prey Veng Province. Human-to-human transmission of A(H5N1) virus was unlikely but genetic susceptibility is suspected. Clusters of A(H5N1) virus infection should be systematically investigated to rule out any human-to-human transmission.

HLA, PTPN22 and PD-1 associations as markers of autoimmunity in neuromyelitis optica

Background: Neuromyelitis optica (NMO) is a disease with autoimmune characteristics. A genetic autoimmune dependency for NMO has not been clarified in detail.

Objective: To investigate immunogenetic aspects of NMO.

Methods: Forty-one patients with NMO and 42 patients with multiple sclerosis (MS) were diagnosed in a population-based Caucasian cohort. HLA DQA1, DQB1, and DRB1 alleles were determined. Polymorphisms in programmed death 1 (PD-1) PD-1.3 G/A and protein tyrosine phosphatase non-receptor 22 (PTPN22) 1858 C/T were genotyped.

Results: In the NMO group 15% had other autoimmune disorders and 39% had family occurrence of autoimmunity, comparable to MS. A higher frequency of a family history (17%) of NMO and MS was found in the NMO group ( p < 0.026). The frequency of HLA-DQB1*0402 allele was increased in NMO ( p after Bonferroni correction, cp < 0.035) and the HLA-DRB1*15 and DQB1*06 alleles were increased in MS ( cp < 0.0027, cp < 0.01), compared to controls. No associations of the PTPN22 1858 T were detected. The PD-1.3A allele was increased both in NMO ( p < 0.0023) and in MS patients ( p < 0.028) compared to controls.

Conclusion: Patients with NMO had frequent co-existence of autoimmunity and family occurrence of NMO and MS. The PD-1.3A allele was associated with NMO. The data suggest genetic autoimmune dependency of NMO.

A population-based study of neuromyelitis optica in Caucasians

BACKGROUND

Epidemiologic studies have suggested different prevalence of neuromyelitis optica (NMO) in different ethnic groups. However, data on the incidence and prevalence of NMO in Caucasians are scarce.

OBJECTIVE

To estimate the incidence and prevalence of NMO in a predominantly Caucasian population based on the Wingerchuk 2006 criteria.

METHODS

The study was a population-based retrospective case series with longitudinal follow-up. Patients with multiple sclerosis (MS), optic neuritis (ON), acute transverse myelitis (TM), and NMO from the 4 neurology and 3 ophthalmology departments in the Region of Southern Denmark having been diagnosed between 1998 and 2008 were investigated. Patients were included based on 1) episodes of ON or TM and 2) an initial brain MRI not diagnostic for MS. An immunofluorescence assay was used to determine aquaporin-4 (AQP-4) antibodies.

RESULTS

A total of 477 patients with MS, TM, or ON were evaluated: 163 fulfilled the inclusion criteria, 42 (26%) qualified for the diagnosis of NMO, 26 (62.0%) of these were AQP4 antibody positive. All except one were Caucasian, the female:male ratio was 2.8:1, and mean age at onset was 35.6 years (range 15-64 years). The clinical presentation was heterogeneous including TM, longitudinally extensive TM, ON, and brainstem syndromes. The yearly incidence rate of NMO in the population was estimated to be 0.4 per 10(5) person-years (95% confidence interval [CI] 0.30-0.54) and the prevalence was 4.4 per 10(5) (95% CI 3.1-5.7).

CONCLUSIONS

Despite being a rare disease, NMO is more common in a Caucasian population than earlier believed.

Neuromyelitis optica (NMO)--an autoimmune disease of the central nervous system (CNS)

In the past 10 years, neuromyelitis optica (NMO) has evolved from Devic's categorical clinical description into a broader disease spectrum. Serum IgG antibodies have been identified in NMO patients with the water channel aquaporin-4 (AQP4) as their main target antigen. AQP4 antibodies/NMO-IgG have been shown to be a highly specific and moderately sensitive serum biomarker for NMO. The immunopathology of NMO lesions supports that anti-AQP4 antibodies/NMO-IgG are involved in the pathogenesis of NMO. In vitro studies have demonstrated that human NMO-IgG induce necrosis and impair glutamate transport in astrocytes. Certain ethnic groups, notably of Asian and African origin, seem to be more susceptible to NMO than others. The genetic background for these putative differences is not known, a weak human leucocyte antigen association has been identified. AQP4 gene variants could represent a genetic susceptibility factor for different clinical phenotypes within the NMO spectrum. Experimental models have been described including a double-transgenic myelin-specific B- and T-cell mouse. NMO-like disease has been induced with passive transfer of human anti-AQP4 antibodies to the plasma of mice with pre-established experimental autoimmune encephalomyelitis or by intrathecal administration to naive mice. NMO may be characterized as a channelopathy of the central nervous system with autoimmune characteristics.

Risk factors for Nipah virus encephalitis in Bangladesh

Patients in Goalando were likely infected by direct contact with fruit bats or their secretions, rather than through contact with an intermediate host.

Nipah virus (NiV) is a paramyxovirus that causes severe encephalitis in humans. During January 2004, twelve patients with NiV encephalitis (NiVE) were identified in west-central Bangladesh. A case–control study was conducted to identify factors associated with NiV infection. NiVE patients from the outbreak were enrolled in a matched case-control study. Exact odds ratios (ORs) and 95% confidence intervals (CIs) were calculated by using a matched analysis. Climbing trees (83% of cases vs. 51% of controls, OR 8.2, 95% CI 1.25–∞) and contact with another NiVE patient (67% of cases vs. 9% of controls, OR 21.4, 95% CI 2.78–966.1) were associated with infection. We did not identify an increased risk for NiV infection among persons who had contact with a potential intermediate host. Although we cannot rule out person-to-person transmission, case-patients were likely infected from contact with fruit bats or their secretions.