Post-poliomyelitis syndrome as a possible viral disease

Post-polio syndrome is not a dysimmune condition

BACKGROUND

Poliomyelitis is a global disabling disease affecting 12-20 million of people. Post poliomyelitis syndrome (PPS) may affect up to 80% of polio survivors: increased muscle weakness, pain, fatigue, functional decline. It relies on aging of an impaired neuro-muscular system with ongoing denervation processes. A late involvement of humoral or cellular pro-inflammatory phenomena is also suspected.

AIM

To assess the dysimmune hypothesis of PPS by comparing lymphocyte subpopulations and humoral immune factors between PPS patients and controls.

DESIGN

Cross-sectional study.

SETTING

Montpellier University Hospital.

POPULATION

Forty-seven PPS and 27 healthy controls.

METHODS

PPS patients and controls were compared on their lymphocyte subpopulations and humoral immune factors (IL-1β, IL-6, IL-8, IL-17, IL-21, IL-22, IL-23, IFN-γ, TNF-α, GM-CSF, RANTES, MCP1, MIP-3a, IL-10, TGF-β, IL4, IL13). Patients were further compared according to their dominant clinical symptoms. Sample size guaranteed a power >90% for all comparisons.

RESULTS

PPS patients and controls were comparable in gender, age and corpulence. Most patients had lower limb motor sequelae (N.=45, 95.7%), a minority had upper limb motor impairment (N.=16, 34.0%). Forty-five were able to walk (94%), 35/45 with technical aids. The median of the two-minute walking test was 110 meters (interquartile range 55; 132). Eighteen (38%) required help in their daily life. Their quality of life was low (SF36). All described an increased muscular weakness, 40 (85%) a general fatigue, and 39 (83%) muscular or joint pain. Blood count, serum electrolytes, T and B lymphocyte subpopulations and cytokines were comparable between patients and controls, except for creatine phospho kinase that was significantly higher in PPS patients. None of these variables differed between the 20/47 patients whose late main symptoms were pain or fatigue, and other patients.

CONCLUSIONS

Our results suggest that PPS is not a dysimmune disease.

CLINICAL REHABILITATION IMPACT

Our results do not sustain immunotherapy for PPS. Our work suggest that PPS may be mostly linked to physiological age-related phenomena in a disabled neuromuscular condition. Thus, our results emphasize the role of prevention and elimination of aggravating factors to avoid late functional worsening, and the importance of rehabilitation programs that should be adapted to patients' specific conditions.

Poliomyelitis is a current challenge: long-term sequelae and circulating vaccine-derived poliovirus

For more than 20 years, the World Health Organization Western Pacific Region (WPR) has been polio-free. However, two current challenges are still polio-related. First, around half of poliomyelitis elderly survivors suffer late poliomyelitis sequelae with a substantial impact on daily activities and quality of life, experiencing varying degrees of residual weakness as they age. The post-polio syndrome as well as accelerated aging may be involved. Second, after the worldwide Sabin oral poliovirus (OPV) vaccination, the recent reappearance of strains of vaccine-derived poliovirus (VDPV) circulating in the environment is worrisome and able to persistent person-to-person transmission. Such VDPV strains exhibit atypical genetic characteristics and reversed neurovirulence that can cause paralysis similarly to wild poliovirus, posing a significant obstacle to the elimination of polio. Immunization is essential for preventing paralysis in those who are exposed to the poliovirus. Stress the necessity of maintaining high vaccination rates because declining immunity increases the likelihood of reemergence. If mankind wants to eradicate polio in the near future, measures to raise immunization rates and living conditions in poorer nations are needed, along with strict observation. New oral polio vaccine candidates offer a promissory tool for this goal.

Immune Response of Gamma-Irradiated Inactivated Bivalent Polio Vaccine Prepared plus Trehalose as a Protein Stabilizer in a Mouse Model

INTRODUCTION

Poliovirus causes paralysis by infecting the nervous system. Currently, 2 types of polio vaccine are given in many countries in polio eradication program including inactivated polio vaccine (IPV) and oral polio vaccine (OPV). Because of OPV-related paralysis, OPV should be replaced by IPV.

METHODS

The aim of this study was to prepare the gamma-irradiated IPV and determine its effectiveness compared with the commercial vaccine (OPV) in the mouse model. The virus titration of OPV was determined and then inactivated by the appropriate dose of gamma radiation into an irradiated vaccine formula. The vaccine was inoculated in BALB/c mice in 2 different formulations of intramuscular injection with 2-week intervals. The level of anti-polio-neutralizing antibody and polio-specific splenocyte proliferation assay were evaluated by collecting the blood samples and spleens of the vaccinated groups with conventional vaccine and irradiated vaccine.

RESULTS

There was a significant increase in the neutralizing antibody titration between all of the vaccinated groups and negative control group (A) (p < 0.05). And it shows that the IPV by gamma irradiation has the highest antibody titration. Also, the increasing of stimulation index value in the B* group, F group, and G group was the most against other groups. Furthermore, the neutralizing anti-serum titer and splenic lymphocyte proliferation assay show humoral and cellular immunity were significantly increased in the irradiated vaccine group as compared with conventional group.

CONCLUSION

According to the results, gamma-irradiated IPV could induce humoral and cellular immunity in vaccinated mouse groups, so the irradiated poliovirus could be recommended as a good candidate vaccine to prevent the transport of poliovirus to the central nervous system and thus protect against paralysis.

Genetic Adaptation of Coxsackievirus B1 during Persistent Infection in Pancreatic Cells

Coxsackie B (CVB) viruses have been associated with type 1 diabetes. We have recently observed that CVB1 was linked to the initiation of the autoimmune process leading to type 1 diabetes in Finnish children. Viral persistency in the pancreas is currently considered as one possible mechanism. In the current study persistent infection was established in pancreatic ductal and beta cell lines (PANC-1 and 1.1B4) using four different CVB1 strains, including the prototype strain and three clinical isolates. We sequenced 5′ untranslated region (UTR) and regions coding for structural and non-structural proteins and the second single open reading frame (ORF) protein of all persisting CVB1 strains using next generation sequencing to identify mutations that are common for all of these strains. One mutation, K257R in VP1, was found from all persisting CVB1 strains. The mutations were mainly accumulated in viral structural proteins, especially at BC, DE, EF loops and C-terminus of viral capsid protein 1 (VP1), the puff region of VP2, the knob region of VP3 and infection-enhancing epitope of VP4. This showed that the capsid region of the viruses sustains various changes during persistency some of which could be hallmark(s) of persistency.

COVID-19 and Guillain-Barré Syndrome: A Case Report and Review of Literature

During the recent coronavirus disease 2019 (COVID-19) outbreak in Northern Italy, we observed a 57-year-old man developing acute motor-sensory axonal neuropathy, a variant of Guillain-Barré syndrome (GBS), 12 days after severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) infection. Similarly to other bacterial and viral infections, dysregulation of the immune system due to post-infectious mechanisms, such as the molecular mimicry, could lead to an indirect damage of the peripheral nervous system related to SARS-CoV-2. GBS causes motor dysfunctions that are not easily recognizable in non-neurological settings or in patients requiring ventilatory assistance. Several reports also suggested that GBS and Miller Fisher syndrome (MFS) could be neurological complications of COVID-19. Therefore, we performed a review of the 29 articles so far published, describing 33 GBS cases and five MFS cases associated with SARS-CoV-2 infection. We recommend awareness of this rare, but treatable, neurological syndrome, which may also determine a sudden and otherwise unexplained respiratory deterioration in COVID-19 patients.

Eradication of persistent coxsackievirus B infection from a pancreatic cell line with clinically used antiviral drugs

BACKGROUND

Persistent enterovirus infections create a difficult therapeutic challenge in immunocompromised patients and may also contribute to the development of chronic diseases including type 1 diabetes, cardiomyopathies, post-polio syndrome and chronic fatigue syndrome.

OBJECTIVES

To study the ability of antiviral drugs to eradicate such infection in vitro to evalaute their potential in the treatments of these patients.

STUDY DESIGN

We set out to evaluate several licensed or clinically tested drugs which have shown some anti-enterovirus activity in previous studies for their ability to cure persistent infection established by two different coxsackievirus B1 strains in a pancreatic cell line (PANC-1 cells).

RESULTS

Among all tested drugs Enviroxime, Fluoxetine, concentrated human IgG product (Hizentra) and Pleconaril were able to eradicate persistent Coxsackievirus B1 infection. The effect Enviroxime, Hizentra and Pleconaril varied between the two virus strains.

CONCLUSIONS

The identified drugs are feasible candidates for clinical trials among patients with persistent coxsackievirus B infections or chronic enterovirus-associated diseases.

Acute Flaccid Myelitis: Lessons From Polio

With the eradication of poliomyelitis in the United States, the appearance of acute flaccid myelitis outbreaks has raised questions regarding their causation. Review of the epidemiology, clinical aspects, and laboratory findings of bygone cases of poliomyelitis have revealed shows important similarities with those of newer cases of acute flaccid myelitis. Many occurrences are preceded by an apparent viral illness, and a number of viruses, particularly enteroviruses A71 and D68, can be isolated from respiratory or stool specimens. Our inability to detect these viruses in cerebrospinal fluid samples from these patients does not eliminate them as etiologic agents, because poliovirus is often not detected in cerebrospinal fluid samples of patients with paralysis caused by poliomyelitis.

Postpolio Syndrome: A Review of Lived Experiences of Patients

Postpolio syndrome (PPS) refers to a group of conditions that are present in patients, years after recovery from initial acute paralytic poliomyelitis. About 15%-80% of 20 million polio survivors worldwide will experience exacerbation of symptoms which typically appear 15-30 years after the resolution of initial poliomyelitis. Symptoms include new muscle weakness, fatigue, myalgia, joint pain, dysphagia, and difficulty breathing. Other reported symptoms include cold intolerance, sleep disorder, dysphonia, loss of stamina, musculoskeletal deformities, cardiovascular disorders, psychosocial problems, and restless legs syndrome. These symptoms are attributed to the superimposed neuronal loss of aging with inflammatory mechanisms, but without any convincing evidence of viral reactivation. Risk factors include female gender, respiratory symptoms, normal aging, permanent disability caused by motor neuron damage, muscle overuse and disuse, aging, and immunologic mechanisms. Hypothyroidism-induced myopathy and fibromyalgia are a differential diagnosis for PPS, and exclusion diagnosis is required as confirmatory criteria for PPS. The symptoms of PPS presented determine the course of management.

Post-poliomyelitis syndrome

Most developed countries eliminated paralytic poliomyelitis (polio) in the 1970s to 1980s. It was believed that after recovery from acute paralytic poliomyelitis, the physical condition of survivors would remain stable for the rest of their lives. However, the elimination of polio does not equate the end of medical management of polio. Hundreds of thousands of polio survivors worldwide are still at risk of developing the late effects of the disease. Here, we report a case of post-polio syndrome who attended our clinic for the presence of new weakness and neuromuscular problems six decades after recovery from paralytic polio. It is essential that health professionals be aware of these conditions and have an understanding of the underlying pathophysiology of the symptoms.

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Post-polio Syndrome: More Than Just a Lower Motor Neuron Disease

Post-polio syndrome (PPS) is a neurological condition that affects polio survivors decades after their initial infection. Despite its high prevalence, the etiology of PPS remains elusive, mechanisms of progression are poorly understood, and the condition is notoriously under-researched. While motor dysfunction is a hallmark feature of the condition, generalized fatigue, sleep disturbance, decreased endurance, neuropsychological deficits, sensory symptoms, and chronic pain are also often reported and have considerable quality of life implications in PPS. The non-motor aspects of PPS are particularly challenging to evaluate, quantify, and treat. Generalized fatigue is one of the most distressing symptoms of PPS and is likely to be multifactorial due to weight-gain, respiratory compromise, poor sleep, and polypharmacy. No validated diagnostic, monitoring, or prognostic markers have been developed in PPS to date and the mainstay of therapy centers on symptomatic relief and individualized rehabilitation strategies such as energy conservation and muscle strengthening exercise regimes. Despite a number of large clinical trials in PPS, no effective disease-modifying pharmacological treatments are currently available.

Amyotrophic Lateral Sclerosis and its Mimics/Variants: A Comprehensive Review

Motor neuron diseases (MNDs) are a debilitating subset of diseases, which result in progressive neuronal destruction and eventual loss of voluntary muscular function. These entities are often challenging to distinguish and accurately diagnose given overlapping clinical pictures and overall rarity. This group of diseases has a high morbidity and mortality rate overall and delineating each type of disease can help guide appropriate clinical management and improve quality of life for patients. Of all MNDs, amyotrophic lateral sclerosis (ALS) is by far the most common comprising 80%-90% of cases. However, other mimics and variants of ALS can appear similar both clinically and radiographically. In this review, we delve into the epidemiological, physiological, neuroimaging, and prognostic characteristics and management of ALS and its most common MND mimics/variants. In doing so, we hope to improve accuracy in diagnosis and potential management for this rare group of diseases.

Growing older with post-polio syndrome: Social and quality-of-life implications

Objectives

To understand the quality-of-life implications for post-polio syndrome survivors.

Methods

For this qualitative study, a focus group methodology, with a case study design, was used. The data were analyzed for themes using a social ecological conceptual framework.

Results

Three focus groups were conducted with a total of 24 participants (N = 24). Participants defined quality of life as being able to engage in meaningful activities of daily living. Participants shared experiences of adapting to declining physical health and embracing new activities of daily living. They expressed hope and shared stories that demonstrated resiliency.

Conclusion

The literature states that individuals aging with post-polio syndrome express concern that health providers often know little about their disability condition. The participants in this study reflected this experience by sharing feelings of misunderstanding from the medical community and expressing a desire to have more dynamic education for health providers.

miRNAs in enterovirus infection

During the last years, it has become evident that miRNAs are important players in almost all physiological and pathological processes, including viral infections. Enterovirus infections range from mild to severe acute infections concerning several organ systems and are also associated with chronic diseases. In this review, we summarize the findings on the impact of acute and persistent enterovirus infection on the expression of cellular miRNAs. Furthermore, the currently available data on the regulation of cellular or viral targets by the dysregulated miRNAs are reviewed. Finally, a translational perspective, namely the use of miRNAs as biomarkers of enterovirus infection and as antiviral strategy is discussed.

Comparison of activity and fatigue of the respiratory muscles and pulmonary characteristics between post-polio patients and controls: A pilot study

OBJECTIVES

To compare pulmonary function measures, maximal respiratory pressure and fatigue of respiratory muscles between patients with Post-Polio Syndrome (PPS) and controls.

DESIGN

Cross-sectional study.

PATIENTS

Patients with PPS (N = 12; age 62.1±11.6 years) able to walk for 6 minutes without human assistance; age-matched controls with no history of polio or pulmonary dysfunction (N = 12; age 62.2±6.5 years).

MEASUREMENTS

A body plethysmograph was used to quantify Residual Volume (RV), Total Lung Capacity (TLC), and Thoracic Gas Volume (TGV) etc. A manometer was used to measure Maximal Inspiratory Pressure (MIP) and Maximal Expiratory Pressure. A spirometer was used to measure Maximal Voluntary Ventilation (MVV). Surface electromyography (sEMG) recorded diaphragmatic muscle activity while performing MVV.

RESULTS

The control group had significantly higher TGV and showed improvement in MIP following the effort (difference of 5.5±4.0cmH2O) while the PPS group showed deterioration in MIP (difference of -2.5±5.0cmH2O). Subjects with scoliosis had significantly higher RV/TLC values compared with subjects without scoliosis. The 25th frequency percentile of the sEMG signal acquired during MVV was reduced in the PPS group.

CONCLUSIONS

Maximal respiratory pressure test and sEMG measurements may identify fatigue of respiratory muscles in patients with PPS. Early diagnosis of respiratory impairment may delay respiratory decline and future need of invasive respiratory aids.

Revealing enterovirus infection in chronic human disorders: An integrated diagnostic approach

Enteroviruses (EVs) causing persisting infection are characterized by minimal replication and genetic changes. Typing of these agents may complement disease assessment and shed light on pathogenesis. Here we report an integrated approach for EV detection in human samples that is based on pre-enrichment of virus in cell culture before search for the viral genome and viral antigens. Cases of post-polio syndrome, type 1 diabetes, and chronic cardiomyopathy were investigated. As tissue-based approaches require invasive procedures, information was mainly gleaned from virus in blood. Molecular assays targeting conserved genome regions of all EV types (5'UTR, 2 C, 3Dpol) were employed. As compared to direct assays of plasma or leukocytes, the EV detection rate was significantly enhanced by co-culture of leukocytes with cell lines prior to molecular and immunologic tests. Results of RT-PCR and sequencing were confirmed by staining cell cultures with a panel of EV-specific antibodies. Sequence and phylogenetic analysis showed that EVs of the C species (polioviruses) were associated with the post-polio syndrome, while members of the B species were found in type 1 diabetes and cardiomyopathy. The procedure may be used for investigating the possible association of different EVs with a variety of chronic neurologic, endocrine, and cardiac disorders.

Optimized production and purification of Coxsackievirus B1 vaccine and its preclinical evaluation in a mouse model

Coxsackie B viruses are among the most common enteroviruses, causing a wide range of diseases. Recent studies have also suggested that they may contribute to the development of type 1 diabetes. Vaccination would provide an effective way to prevent CVB infections, and the objective of this study was to develop an efficient vaccine production protocol for the generation of novel CVB vaccines. Various steps in the production of a formalin-inactivated Coxsackievirus B1 (CVB1) vaccine were optimized including the Multiplicity Of Infection (MOI) used for virus amplification, virus cultivation time, type of cell growth medium, virus purification method and formulation of the purified virus. Safety and immunogenicity of the formalin inactivated CVB1 vaccine was characterized in a mouse model. Two of the developed methods were found to be optimal for virus purification: the first employed PEG-precipitation followed by gelatin-chromatography and sucrose cushion pelleting (three-step protocol), yielding 19-fold increase in virus concentration (0.06µg/cm²) as compared to gold standard method. The second method utilized tandem sucrose pelleting without a PEG precipitation step, yielding 83-fold increase in virus concentration (0.24µg/cm²), but it was more labor-intensive and cannot be efficiently scaled up. Both protocols provide radically higher virus yields compared with traditional virus purification protocols involving PEG-precipitation and sucrose gradient ultracentrifugation. Formalin inactivation of CVB1 produced a vaccine that induced a strong, virus-neutralizing antibody response in vaccinated mice, which protected against challenge with CVB1 virus. Altogether, these results provide valuable information for the development of new enterovirus vaccines.

VP3 is crucial for the stability of Nora virus virions

Nora virus is an enteric virus that causes persistent, non-pathological infection in Drosophila melanogaster. It replicates in the fly gut and is transmitted via the fecal-oral route. Nora virus has a single-stranded positive-sense RNA genome, which is translated in four open reading frames. Reading frame three encodes the VP3 protein, the structure and function of which we have investigated in this work. We have shown that VP3 is a trimer that has an α-helical secondary structure, with a functionally important coiled-coil domain. In order to identify the role of VP3 in the Nora virus life cycle, we constructed VP3-mutants using the cDNA clone of the virus. Our results show that VP3 does not have a role in the actual assembly of the virus particles, but virions that lack VP3 or harbor VP3 with a disrupted coiled coil domain are incapable of transmission via the fecal-oral route. Removing the region downstream of the putative coiled coil appears to have an effect on the fitness of the virus but does not hamper its replication or transmission. We also found that the VP3 protein and particularly the coiled coil domain are crucial for the stability of Nora virus virions when exposed to heat or proteases. Hence, we propose that VP3 is imperative to Nora virus virions as it confers stability to the viral capsid.

[Emerging viral infections and hepatotropic virus]

Environmental degradation, population movements and urban agglomerations have broken down the borders for infectious diseases. The expansion of microorganisms has entered an increasing area of transmission vectors. The lack of immunity of the population leads to an increased risk of spreading infectious diseases. Furthermore, the decline in vaccination rates in developed countries and socio-economic difficulties in large regions has meant that diseases in the process of eradication have re-emerged. That is why health care workers must be trained to avoid delaying in diagnosis and to accelerate the implementation of public health measures. A great deal of education and health prevention should fall under the responsibilities of travellers who move around different regions.

Autoimmunity in picornavirus infections

Enteroviruses are small, non-enveloped, positive-sense single-strand RNA viruses, and are ubiquitously found throughout the world. These viruses usually cause asymptomatic or mild febrile illnesses, but have a propensity to induce severe diseases including type 1 diabetes and pancreatitis, paralysis and neuroinflammatory disease, myocarditis, or hepatitis. This pathogenicity may result from induction of autoimmunity to organ-specific antigens. While enterovirus-triggered autoimmunity can arise from multiple mechanisms including antigenic mimicry and release of sequestered antigens, the recent demonstration of T cells expressing dual T cell receptors arising as a natural consequence of Theiler's virus infection is the first demonstration of this autoimmune mechanism.