Next-generation sequencing combined with serological tests based pathogen analysis for a neurocysticercosis patient with a 20-year history:a case report.

BACKGROUND: Neurocysticercosis (NCC) is the most common helminthic infection of the central nervous system (CNS) caused by the larval stage of Taenia solium. Accurate and early diagnosis of NCC remains challenging due to its heterogeneous clinical manifestations, neuroimaging deficits, variable sensitivity, and specificity of serological tests. Next-generation sequencing (NGS)-based pathogen analysis in patient's cerebrospinal fluid (CSF) with NCC infection has recently been reported indicating its diagnostic efficacy. In this case study, we report the diagnosis of a NCC patient with a symptomatic history of over 20 years using NGS analysis and further confirmation of the pathology by immunological tests. CASE PRESENTATION: This study reports the clinical imaging and immunological features of a patient with a recurrent headache for more than 20 years, which worsened gradually with the symptom of fever for more than 7 years and paroxysmal amaurosis for more than 1 year. By utilizing NGS technique, the pathogen was detected in patient's CSF, and the presence of Taenia solium-DNA was confirmed by a positive immunological reaction to cysticercus IgG antibody in CSF and serum samples. The symptoms of the patient were alleviated, and the CSF condition was improved substantially after the anti-helminthic treatment. CONCLUSIONS: This study suggests that combining CSF NGS with cysticercus IgG testing may be a highly promising approach for diagnosing the challenging cases of NCC. Further studies are needed to evaluate the parasitic DNA load in patients' CSF for the diagnosis of disease severity, stage, and monitoring of therapeutic responses.

Taenia solium proteins: a beautiful kaleidoscope of pro and anti-inflammatory antigens.

Background: Neurocysticercosis (NCC) is an acquired infection of central nervous system associated with epileptic seizures. The parasite 'Taenia solium' causes this disease and has a complex life cycle and molts into various stages that influence the host-parasite interaction. The disease has a long asymptomatic phase with viable cyst and degeneration of cyst and leaking cyst fluid has been associated with symptomatic phase. The parasite proteome holds the answers and clues to this complex clinical presentation and hence unraveling of proteome of parasite antigens is needed for better understanding of host-parasite interactions. Objective: To understand the proteome make-up of T. solium cyst vesicular fluid (VF) and excretory secretory proteins (ESPs). Methodology: The VF and ESPs for the study were prepared from cyst harvested from naturally infected swine. The samples were prepared for nano LC-MS by in-tube digestion of proteins. The spectra obtained were annotated and enrichment analysis was performed and in silico analysis was done. Results:T. solium VF and ESPs have 206 and 247 proteins of varied make-up including pro-inflammatory and anti-inflammatory nature. Conclusions: Due to varied make-up of VF and ESPs it can generate complex humoral and cellular immune response.

Granulomas in parasitic diseases: the good and the bad.

Parasitic diseases affect more than one billion people worldwide, and most of them are chronic conditions in which the treatment and prevention are difficult. The appearance of granulomas, defined as organized and compact structures of macrophages and other immune cells, during various parasitic diseases is frequent, since these structures will only form when individual immune cells do not control the invading agent. Th2-typering various parasitic diseases are frequent, since these structures will only form when individual immune cells do not control the invading agent. The characterization of granulomas in different parasitic diseases, as well as recent findings in this field, is discussed in this review, in order to understand the significance of the granuloma and its modulation in the host-parasite interaction and in the immune, pathological, and parasitological aspects of this interaction. The parasitic granulomatous diseases granulomatous amebic encephalitis, toxoplasmosis, leishmaniasis, neurocysticercosis, and schistosomiasis mansoni are discussed as well as the mechanistic and dynamical aspects of the infectious granulomas.

Neurocysticercosis and pharmacoresistant epilepsy: possible role of calcified lesions in epileptogenesis.

Neurocysticercosis is a neglected and usually poverty-related disease of high public importance. The mechanisms by which the calcified lesions cause epilepsy are not known, but have been attributed to residual perilesional gliosis or an inflammatory process. This case shows that an inflammatory response to a calcified granuloma may be associated with the development of epilepsy. The increase in glutamate and kinin B1 (pro-epileptogenic) receptors added by reduced expression of kinin B2 (anti-epileptogenic) receptors may explain the chronic epileptogenesis associated with the lesion, corroborating the hypothesis of inflammatory mechanisms involved in the pathophysiology of epilepsy in these patients.

Unique Characteristics of Epilepsy Development in Neurocysticercosis.

The parasitic helminth infection neurocysticercosis (NCC) is the most common cause of adult-acquired epilepsy in the world. Despite the serious consequences of epilepsy due to this infection, an in-depth review of the distinct characteristics of epilepsy due to neurocysticercosis has never been conducted. In this review, we evaluate the relationship between NCC and epilepsy and the unique characteristics of epilepsy caused by NCC. We also discuss recent advances in our understanding of NCC-related epilepsy, including the importance of anti-inflammatory therapies, the association between NCC and temporal lobe epilepsy, and the recent discovery of biomarkers of severe epilepsy development in individuals with NCC and seizures.

Host immune responses during Taenia solium Neurocysticercosis infection and treatment.

Taenia solium cysticercosis and taeniasis (TSCT), caused by the tapeworm T. solium, is a foodborne and zoonotic disease classified since 2010 by WHO as a neglected tropical isease. It causes considerable impact on health and economy and is one of the leading causes of acquired epilepsy in most endemic countries of Latin America, Sub-Saharan Africa, and Asia. There is some evidence that the prevalence of TSCT in high-income countries has recently increased, mainly due to immigration from endemic areas. In regions endemic for TSCT, human cysticercosis can manifest clinically as neurocysticercosis (NCC), resulting in epileptic seizures and severe progressive headaches, amongst other neurological signs and/or symptoms. The development of these symptoms results from a complex interplay between anatomical cyst localization, environmental factors, parasite's infective potential, host genetics, and, especially, host immune responses. Treatment of individuals with active NCC (presence of viable cerebral cysts) with anthelmintic drugs together with steroids is usually effective and, in the majority, reduces the number and/or size of cerebral lesions as well as the neurological symptoms. However, in some cases, treatment may profoundly enhance anthelmintic inflammatory responses with ensuing symptoms, which, otherwise, would have remained silent as long as the cysts are viable. This intriguing silencing process is not yet fully understood but may involve active modulation of host responses by cyst-derived immunomodulatory components released directly into the surrounding brain tissue or by the induction of regulatory networks including regulatory T cells (Treg) or regulatory B cells (Breg). These processes might be disturbed once the cysts undergo treatment-induced apoptosis and necrosis or in a coinfection setting such as HIV. Herein, we review the current literature regarding the immunology and pathogenesis of NCC with a highlight on the mobilization of immune cells during human NCC and their interaction with viable and degenerating cysticerci. Moreover, the immunological parameters associated with NCC in people living with HIV/AIDS and treatments are discussed. Eventually, we propose open questions to understand the role of the immune system and its impact in this intriguing host-parasite crosstalk.

Development of multi-epitope chimeric vaccine against Taenia solium by exploring its proteome: an in silico approach.

Objective: Taenia solium is a neglected tropical disease; larvae of this parasite infect central nervous system i.e. Neurocysticercosis, and adults mature and survive into intestine i.e. Taeniasis. Globally more than 50 million people are at the risk of infection. This is one of the main etiological agents for onset of new early epilepsy in developing countries. However, there is no vaccine available to protect human from its infection. Hence, there is an urgent need for a good vaccine.Methods: We applied immune-informatics approach to design a multi-epitope chimeric vaccine consisting of both B and T-cell epitopes.Results: From the whole transcriptome of Taenia, we identified five suitable peptides present on cell membrane, epitope identification on these peptides were done by using various immunoinformatic software. Physiochemical properties were determined and the tertiary structure of vaccine was predicted, validated and refined, and to increase antigenicity we added linker to them. Best-modeled protein-complex was used for docking study with TLR1-2, TLR4, TLR3 and TLR7 and stability of molecular complex was determined by molecular dynamics simulation.Conclusions: Overall, we attempted to design an efficient subunit chimeric vaccine, which could stimulate humoral and cellular immune responses and could protect against both neurocysticercosis and taeniasis.

IgY antibody and human neurocysticercosis: a novel approach on immunodiagnosis using Taenia crassiceps hydrophobic antigens.

Human neurocysticercosis (NCC) is a worldwide neglected disease caused by Taenia solium metacestode and responsible for various complications and neurological disorders. This study aimed to evaluate the use of specific immunoglobulin Y (IgY) produced by laying hens immunized with a hydrophobic fraction of Taenia crassiceps metacestodes (hFTc) in NCC diagnosis. Egg yolk IgY antibodies were fractionated, purified and characterized. Enzyme-linked immunosorbent assay (ELISA) was carried out to evaluate the production kinetics and avidity maturation of anti-hFTc IgY antibodies throughout the IgY obtention process. Antigen recognition tests were carried out by Western blotting and immunofluorescence antibody test using purified and specific anti-hFTc IgY antibodies for detection of parasitic antigens of T. crassiceps and T. solium metacestodes. Sandwich ELISA was performed to detect circulating immune complexes formed by IgG and parasitic antigens in human sera. The results showed high diagnostic values (93.2% sensitivity and 94.3% specificity) for immune complexes detection in human sera with confirmed NCC. In conclusion, specific IgY antibodies produced from immunized hens with hFTc antigens were efficient to detect T. solium immune complexes in human sera, being an innovative and potential tool for NCC immunodiagnosis.

Sorting out difficulties in immunological diagnosis of neurocysticercosis: Development and assessment of real time loop mediated isothermal amplification of cysticercal DNA in blood.

PURPOSE OF THE STUDY: Among various immunological tests available for diagnosis of neurocysticercosis (NCC), only EITB (Electroimmunotransfer blot for detection of anticysticercal antibodies) had gained widespread acceptance. However EITB is not available widely and is costly (Indian rupees 15,000/- approximately). We evaluated utility of Loop mediated isothermal amplification (LAMP) assay for detection of Taenia solium cox1 gene in blood of patients with NCC. PATIENTS AND METHODS: Current study included 100 consecutive patients of NCC at a tertiary teaching hospital in Northern India. All the patients underwent detailed history and examinations as well as gadolinium enhanced magnetic resonance imaging of brain. LAMP assay was performed in all the patients. The results were compared with 50 controls. RESULTS: LAMP detected Taenia Solium cox1 gene in 74% of all blood samples in patients of NCC.T he overall sensitivity of LAMP assay for detection of cox1 gene was 74% in all patients with NCC, 71.8% in patients with intraparenchymal brain cysts only and 86.7% of patients with extraparenchymal brain cysts with or without intraparenchymal brain cysts. The overall specificity of LAMP assay was 90% in all these three subgroups. The positive predictive value of real time LAMP assay was close to 93% for almost all forms of NCC- both solitary and multiple while negative predictive value ranged from 57 to 64%. CONCLUSION: Real time LAMP assay of blood for detection of Taenia solium cox1 gene appears to be a promising toll for diagnosis of NCC.

Feasibility of a point-of-care test based on quantum dots with a mobile phone reader for detection of antibody responses.

We developed a novel and portable fluorescent sensor that integrates a lateral flow assay with a quantum dot (Qdots) label and a mobile phone reader for detection of specific antibodies in human serum. We evaluated the utility of this assay to test for antibodies to the Taenia solium rT24H antigen. It was a retrospective study by examining 112 positive human sera from patients with neurocysticercosis (NCC) including samples from patients with single viable cyst (n = 18), two or more viable cysts (n = 71), and subarachnoid (racemose) cysts (n = 23). These samples were collected from previous study subjects in Lima, Peru under an approved study protocol in Peru. The sera were made anonymous under a protocol approved by the CDC Institutional Review Board. Definitive diagnosis of the subject was established by computed-tomography and/or magnetic resonance imaging. To test the specificity of the assay, we evaluated a panel of serum samples obtained from patients with other infections (n = 24), and serum samples from persons in the United States and Egypt who had not traveled outside their country, and therefore are presumed negative for cysticercosis (n = 128). The assay specificity in the negative panel was 99% (95-100%) while assay sensitivity was 89% (79-95%) in NCC patients with two or more viable cysts. Our assay has performance characteristics similar to those of traditional platforms for the detection of NCC and shows promise as a mobile phone reader-based point-of-care test for antibody detection.

Neurocysticercosis: A new concept and insight into basic and future pharmacotherapy.

Neurocysticercosis is a neurological infection caused by the larva of taenia solium. The larva infection may affect different parts of the human brain and spinal cord, leading to focal neurological deficit with/without inflammatory reactions. Neurocysticercosis is one of the major causes of epilepsy in the developing countries. It is of two types. One is extra-parenchymal neurocysticercosis in which cysticerci cysts at subarachinoid space and ventricles lead to obstructive hydrocephalus and increase in the intracranial pressure. The other type is intra-parenchymal neurocysticercosis in which the cysticerci cyst grows inside the brain parenchyma, causing the feature of space-occupying lesion. The common presentation of intra-parenchymal neurocysticercosis is secondary epilepsy which is due to focal lesion and/or local inflammatory reactions. Cysticidal therapy increases the risk of seizure due to the induction of host inflammatory reactions. Therefore, coadministration of corticosteroids reduces the risk of seizure through attenuation of inflammatory reactions and brain oedema. Praziquantel alone or in combination with albendazole is regarded as the basic cysticidal therapy against neurocysticercosis. Newer drugs and agents are recommended to overcome the partial failure of standard cysticidal therapy.

Immunodiagnosis of human neurocysticercosis: comparative performance of serum diagnostic tests in Mexico.

Immunodiagnosis has a supportive role in the diagnosis of neurocysticercosis (NCC). The aim of this study was to compare the validity of seven immunodiagnostic tests among serum samples from 58 patients with NCC, 26 patients with neurological diseases other than NCC, and 15 healthy controls. One test for viable parasite detection (HP10 antigen assay) and six for antibody detection were evaluated. For the entire sample, sensitivities ranged from 55.2% (NOVALISA) to 81.0% (enzyme-linked immunosorbent assay [ELISA] Taenia solium antibody), with the sensitivity of the latter test significantly higher than that of the in-house ELISA Taenia crassiceps, NOVALISA, enzyme-linked immunoelectrotransfer blot (EITB) CDC, and HP10. Overall, specificities were high, ranging from 85.4% (ELISA Ts) to 97.1% (NOVALISA), with no statistically significant differences. Detection of HP10 antigen was significantly associated with the presence of vesicular parasites. The simple and low-cost ELISA Taenia solium antibody Ab instead of EITB is recommended to support NCC diagnosis in both rural and hospital settings in Mexico.

Distribution of Taenia solium Diagnostic Glycoproteins in the Different Developmental Stages of the Parasite.

Taenia solium is a helminth parasite that causes 2 diseases in humans: cysticercosis and taeniasis. The establishment of T. solium metacestodes in the central nervous system causes neurocysticercosis, while development of the adult tapeworm in the small intestine causes taeniasis. Serological diagnosis of neurocysticercosis is performed by Western blot with an enriched fraction of glycoproteins that has been extensively used for clinical diagnosis and epidemiological surveys. The lectin-bound fraction that is used for this assay contains 7 antigenic glycoproteins. These antigenic proteins are considered to be highly specific for cysticercosis when tested with heterologous parasitic diseases. However, recent studies show that people with taeniasis have cross-reactive antibodies against the neurocysticercosis diagnostic glycoproteins and vice versa. Nevertheless, it is not known if these diagnostic proteins are expressed in the adult stage of the parasite. In this paper, we describe the location of 3 of these glycoproteins in T. solium adults and cysticerci using polyclonal antibodies raised against a synthetic peptide based on the amino acid sequence of TS14, a recombinant protein T24H, and the native GP50. The glycoproteins' distribution was different in invaginated and evaginated cysticerci as well as in adult tapeworms. Specifically, the 3 glycoproteins studied were differentially expressed during embryogenesis. Our findings indicate that expression of the diagnostic glycoproteins is developmentally regulated; this is noteworthy since these glycoproteins are considered specific for the diagnosis of neurocysticercosis but nevertheless are present in different structures throughout the development of T. solium. Here we describe the glycoprotein expression and localization, which can be important in understanding their biological functions. In addition, our results help clarify the cross-reaction observed between people with neurocysticercosis and taeniasis to TS14, T24H, and GP50, which are used as diagnostic antigens for neurocysticercosis.

Neurocysticercosis and HIV Infection: what can we learn from the published literature?

OBJECTIVE: Infections caused by the human immunodeficiency virus (HIV) and by the larvae of Taenia solium (i.e., cysticercosis) are still widespread in many developing countries. Both pathologies modify host immune status and it is possible that HIV infection may modulate the frequency and pathogeny of cysticercosis of the central nervous system (i.e., neurocysticercosis [NCC]). To describe published cases of NCC among HIV-positive patients and to evaluate whether the characteristics of NCC, including frequency, symptoms, radiological appearance, and response to treatment differed between HIV-positive and HIV-negative patients. METHODS: Forty cases of NCC/HIV co-infected patients were identified in the literature. Clinical and radiological characteristics, as well as response to treatment, were compared with non-matching historical series of NCC patients without HIV infection. RESULTS: Most of these patients had seizures and multiple vesicular parasites located in parenchyma. Clinical and radiological characteristics were similar between HIV-positive and HIV-negative patients with NCC, as well as between immunocompromised and non-immunocompromised HIV-positive patients. CONCLUSION: Our review did not reveal clear interactions between HIV and NCC. This may be partially due to the small number of cases and reliance on published research. A systematic, multi-institutional effort aiming to report all the cases of this dual pathology is needed to confirm this finding and to clarify the possible relationship between both pathogens.

Neurocysticercosis and HIV Infection: what can we learn from the published literature? / Neurocisticercosis e infección por VIH: ¿Qué se puede aprender de la literatura reportada?

ABSTRACT Infections caused by the human immunodeficiency virus (HIV) and by the larvae of Taenia solium (i.e., cysticercosis) are still widespread in many developing countries. Both pathologies modify host immune status and it is possible that HIV infection may modulate the frequency and pathogeny of cysticercosis of the central nervous system (i.e., neurocysticercosis [NCC]). Objective: To describe published cases of NCC among HIV-positive patients and to evaluate whether the characteristics of NCC, including frequency, symptoms, radiological appearance, and response to treatment differed between HIV-positive and HIV-negative patients. Methods: Forty cases of NCC/HIV co-infected patients were identified in the literature. Clinical and radiological characteristics, as well as response to treatment, were compared with non-matching historical series of NCC patients without HIV infection. Results: Most of these patients had seizures and multiple vesicular parasites located in parenchyma. Clinical and radiological characteristics were similar between HIV-positive and HIV-negative patients with NCC, as well as between immunocompromised and non-immunocompromised HIV-positive patients. Conclusion: Our review did not reveal clear interactions between HIV and NCC. This may be partially due to the small number of cases and reliance on published research. A systematic, multi-institutional effort aiming to report all the cases of this dual pathology is needed to confirm this finding and to clarify the possible relationship between both pathogens.

RESUMO Las infecciones causadas por el virus de inmunodeficiencia humana (VIH) y la larva de la Tenia solium siguen estando diseminadas en países en vías de desarrollo. Ambas patologías modifican el estado inmune y es posible que la infección por el VIH module la frecuencia y la patología de la neurocisticercosis (NCC). Objetivo: Describir los casos publicados de NCC en los pacientes VIH positivos y evaluar si las características de la NCC, incluyendo frecuencia, síntomas, presentación radiológica, respuesta a tratamiento, difieren entre los sujetos VIH positivos y VIH negativos. Métodos: Cuarenta casos con coinfección NCC/VIH fueron identificados en la literatura. Se compararon sus características clínico-radiológicas, así como su respuesta al tratamiento con diferentes series de casos históricos no pareados. Resultados: La mayoría de los pacientes NCC/VIH tenían epilepsia y múltiples parásitos vesiculares en el parénquima. Las características clínico-radiológicas de la NCC así como la evolución de los pacientes fueron similares entre pacientes VIH positivos y negativos, así como entre pacientes VIH inmunocomprometidos y no inmunocomprometidos. Conclusión: No encontramos interacciones claras entre VIH y NCC. Este resultado puede haber sido influenciado por el pequeño número de casos y la parcialidad de la información publicada. Un esfuerzo multiinstitucional, sistemático encaminado a reportar todos los casos de esta patología dual es necesario para confirmar estos resultados y esclarecer la relación entre patógenos.

Monitoring treatment of Taenia solium- neurocysticercosis by detection of circulating antigens: a case report.

BACKGROUND: Parenchymal neurocysticercosis is a frequent cause of seizures in areas endemic for Taenia solium. At present there is scarce data on the evolution of the levels of circulating metacestodal antigen before, during and after treatment with anthelmintic drugs. CASE PRESENTATION: A patient with paucisymptomatic neurocysticercosis (NCC) diagnosed by Ag-ELISA, and confirmed by MRI images, was treated with praziquantel, albendazole and dexamethasone. The level of circulating T. solium antigen was determined weekly. Circulating antigen disappeared from his blood within 14 days after the start of the treatment and correlated with the involution of the cysticerci in the brain shown by imaging. Seventeen years later, the patient has not shown any side effect nor symptoms related to the treatment or to NCC. CONCLUSIONS: If this encouraging finding is confirmed in a larger series of patients, this technique could be used to determine parasitological cure after treatment and might complement or sometimes replace sequential MRI-imaging of the brain.

Treatment-Resistant Human Extraparenchymal Neurocysticercosis: An Immune-Inflammatory Approach to Cysticidal Treatment Outcome.

OBJECTIVE: The aim of this study is to analyze the immune-endocrine profile in neurocysticercosis (NC) patients resistant to cysticidal treatment. METHODS: The inflammatory and regulatory responses of 8 resistant NC patients with extraparenchymal parasites and 5 healthy controls were evaluated through flow cytometry. Serum interleukin levels were measured by ELISA and catecholamines levels by high performance liquid chromatography. RESULTS: Higher percentages of Tr1, CD4+CD25+FOXP3+CD127- and CD4+CD45RO+FOXP3HI were found in NC patients compared with healthy controls, but no difference was found in catecholamine levels. Antigen-specific proliferative immune response was observed in NC patients. Neither anti-inflammatory nor pro-inflammatory cytokines showed differences between patients and controls, but IL-6 levels were lower in treatment-resistant NC patients. In addition, TGFß showed a significant negative correlation with dopamine. CONCLUSIONS: Altogether, these results may point to a modulation of the neuroinflammation in these patients that could indirectly favor cysticercal survival in CNS microenvironment.

Histopathologic aspects of experimental cysticercosis and in situ cytokines profile in C57BL/6 mice.

Neurocysticercosis (NCC) is one of the parasitic infections that most affects the central nervous system. The knowledge regarding its immunopathogenesis and pathophysiology needs broadening. Taenia crassiceps cysticerci are used as the NCC experimental model. The aim of this work was to describe the general pathological processes and the in situ cytokine profile in C57BL/6 mice inoculated intracranially with viable T. crassiceps cysticerci. The histopathology analysis showed cysticerci in the extraparenchymal and intraventricular region, mononuclear inflammatory infiltration surrounding the parasite, microgliosis and meningitis. The analysis of the in situ immune profiles showed a predominance of the Th2 response. The IL-4 and IL-10 dosages were significantly increased in the infected group. The decrease in the INF-gamma dosage reflects the immunomodulation from the cysticerci. In conclusion, a T. crassiceps NCC infection in C57BL/6 mice triggers an inflammatory response, a predominance of Th2 type in situ profile, with mononuclear inflammatory cell infiltration, meningitis and microgliosis.