HLA-DR3-DQ2 Mice Do Not Develop Ataxia in the Presence of High Titre Anti-gliadin Antibodies

Ultrasound-responsive hyaluronic acid hydrogel of hydrocortisone to treat osteoarthritis

One of the practical ways to manage the disease flares of arthritis is using an intra-articular depot formulation of glucocorticoids. Hydrogels, as controllable drug delivery systems, are hydrophilic polymers with distinctive properties, such as remarkable water capacity and biocompatibility. This study aimed to design an injectable thermo-ultrasound-triggered drug carrier based on Pluronic® F-127, hyaluronic acid, and gelatin. The in situ hydrogel loaded by hydrocortison was developed and D-optimal design was used to formulate the process. The optimized hydrogel was combined with four different surfactants to better regulate the release rate. In situ gels composed of the hydrocortisone-loaded hydrogel and hydrocortisone-loaded mixed-micelle hydrogel were characterized. The hydrocortisone-loaded hydrogel and selected hydrocortisone-loaded mixed-micelle hydrogel showed a spherical shape and were nano-sized with a unique thermo-responsive nature able to prolong drug release. The ultrasound-triggered release study showed that drug release was time-dependent. By inducing osteoarthritis in a rat model, behavioral tests and histopathological analyses were carried out on the hydrocortisone-loaded hydrogel and a particular hydrocortisone-loaded mixed-micelle hydrogel. In vivo results showed that the selected hydrocortisone-loaded mixed-micelle hydrogel improved the status of the disease. Results highlighted the potential of ultrasound-responsive in situ-forming hydrogels as hopeful formulas for efficient treatment of arthritis.

Dietary Gluten and Neurodegeneration: A Case for Preclinical Studies

Although celiac disease (CD) is an autoimmune disease that primarily involves the intestinal tract, mounting evidence suggests that a sizeable number of patients exhibit neurological deficits. About 40% of the celiac patients with neurological manifestations have circulating antibodies against neural tissue transglutaminase-6 (tTG6). While early diagnosis and strict adherence to a gluten-free diet (GFD) have been recommended to prevent neurological dysfunction, better therapeutic strategies are needed to improve the overall quality of life. Dysregulation of the microbiota-gut-brain axis, presence of anti-tTG6 antibodies, and epigenetic mechanisms have been implicated in the pathogenesis. It is also possible that circulating or gut-derived extracellular structures and including biomolecular condensates and extracellular vesicles contribute to disease pathogenesis. There are several avenues for shaping the dysregulated gut homeostasis in individuals with CD, non-celiac gluten sensitivity (NCGS) and/or neurodegeneration. In addition to GFD and probiotics, nutraceuticals, such as phyto and synthetic cannabinoids, represent a new approach that could shape the host microbiome towards better prognostic outcomes. Finally, we provide a data-driven rationale for potential future pre-clinical research involving non-human primates (NHPs) to investigate the effect of nutraceuticals, such as phyto and synthetic cannabinoids, either alone or in combination with GFD to prevent/mitigate dietary gluten-induced neurodegeneration.

Nonparaneoplastic autoimmune cerebellar ataxias

PURPOSE OF REVIEW

The current review develops the clinical presentations of nonparaneoplastic autoimmune cerebellar ataxia (ACA) and analyzes the association with autoantibodies.

RECENT FINDINGS

Emerging evidence suggests that autoimmunity is involved in a significant proportion of sporadic ataxia cases. Moreover, numerous autoantibodies have recently been described in association with sporadic cerebellar ataxia, improving diagnosis and patient categorization.

SUMMARY

Nonparaneoplastic ACA encompasses postinfectious acute cerebellar ataxia, opsoclonus-myoclonus-ataxia syndrome, and pure cerebellar ataxia with or without autoantibodies. There is still confusion about how to diagnose and classify the patients, and retrospective data suggest that these very rare entities are in fact largely underrecognized. Numerous autoantibodies have been found associated with sporadic ataxia, improving diagnosis accuracy, and patient categorization. However, although anti-glutamate decarboxylase isotype 65 (GAD65), anti-contactin-associated protein 2 (CASPR2), and anti metabotropic glutamate receptor (mGluR1) antibodies are well recognized biomarkers, many other autoantibodies have been described in very small numbers of patients and their specificity is unknown. Efficient biomarkers for ACA are still lacking and in many cases the diagnosis has to rely on a body of converging evidence.

Coeliac disease patients do not produce antibodies to a common cerebellar epitope

Background

Most adult-onset sporadic ataxias are unexplained, and the claim that many of these may be a result of gluten sensitivity has led to uncertainty as to whether to test for anti-gliadin antibodies (αGAb) and, if present, whether to recommend a gluten-free diet or continue searching for other causes of ataxia. This uncertainty arises in part from the frequency of αGAb in the population (about 1 in 10), but recent work delineating transglutaminase 6 as the target antigen in gluten ataxia has clarified the situation somewhat. Our aim was to determine whether there is molecular mimicry between cerebellar Purkinje cell antigens and gluten in subjects selected for recent diagnosis of CD rather than for ataxia.

Results

High titre αGAb sera from 11 newly-diagnosed CD patients and normal sera from 10 healthy controls were used to detect cross-reacting antibodies to cerebellar and cerebral cortex antigens in mouse, monkey and human tissue. None of the CD patients displayed ataxia. Mouse and human cerebellar and cerebral cortex extracts were analysed by Western blot probed with CD and control sera. Immunofluorescence microscopy was used on mouse and monkey cerebellar sections immunostained with CD and control sera to detect cross-reacting IgG antibodies.

Western blot analysis of cerebellar and cerebral cortex extracts probed with CD sera did not demonstrate any specific immunoreactivity unique to the cerebellum. An identical twin pair with CD produced different patterns of reactivity. Immunofluorescence staining of mouse and monkey cerebellar sections showed most control and CD sera reacted non-specifically, with the exception of two CD and one control sera, each having a unique staining pattern.

Conclusions

CD patient sera with high titre αGAb do not detect a common Purkinje cell or cerebellar-specific epitope. The pattern of reactivity is not solely dependent on genetic background.