Neuroimmunology and Multiple Sclerosis Unit of Girona
Neurology Department of Josep Trueta University Hospital

Author Of 1 Presentation

Disease Modifying Therapies – Risk Management Oral Presentation

PS09.03 - Predictive biomarkers of the development of autoimmunity in patients treated with alemtuzumab

Speakers
Presentation Number
PS09.03
Presentation Topic
Disease Modifying Therapies – Risk Management
Lecture Time
09:45 - 09:57

Abstract

Background

Alemtuzumab has proven to be an effective treatment for patients with highly active multiple sclerosis (MS). However, its use has been limited by adverse events (AEs) as secondary autoimmunity, being the most frequent those involving the thyroid gland, observed in around 40% of patients.

Objectives

To explore whether patient blood lymphocyte profile before alemtuzumab treatment initiation can identify patients with an increased risk of developing later autoimmunity.

Methods

A multicentre prospective longitudinal study was performed, including fifty‐four Relapsing-Remitting MS (RRMS) patients diagnosed in five Spanish hospitals. Patient blood samples were collected before initiating treatment with alemtuzumab. Autoimmune AEs were defined as the development, at any point within 2 years of follow-up, of any autoimmune thyroid-associated event, immune thrombocytopenia and/or autoimmune nephropathy. Differences were assessed using Man-Whitney U tests. Cut-off values were established using ROC curves to predict autoimmune AEs. Odds ratios were calculated by Fisher tests.

Results

Fifty‐four RRMS patients, 36 (66.7%) women, with a median (range) age of 28 (13–67) years and median (range) follow-up of 6 (0-20) years. Fourteen patients (25.9%) experienced autoimmune AEs, and all of them were dysthyroidism. No immune thrombocytopenia or nephropathies were observed. No statistical differences were found in clinical and demographic characteristics between patients who developed autoimmune AEs and those who did not. Patients who experienced autoimmune AEs before treatment onset had a higher percentage of blood CD19+ B cells (p=0.001), with a higher relative percentage of naïve B cells and plasmablasts. When explored total cell numbers, only plasmablast levels remained significant (p=0.02). A lower risk of autoimmune AEs after alemtuzumab was observed among patients with less than 7.6% of blood CD19+ B cells [odds ratio (OR) 16, confidence interval (CI) 3.86–58.95, p<0.0001] or less than 0.13% of plasmablast cells [OR 9.33, CI 2.17–42.65, p=0.002].

Conclusions

A low percentages of blood CD19+ B cells or plasmablasts before Alemtuzumab treatment predicted a lower risk of autoimmune AEs.

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Author Of 9 Presentations

Diagnostic Criteria and Differential Diagnosis Poster Presentation

P0245 - An unusual mimic of progression in Multiple Sclerosis patients (ID 253)

Speakers
Presentation Number
P0245
Presentation Topic
Diagnostic Criteria and Differential Diagnosis

Abstract

Background

Superficial siderosis (SS) is a rare disease caused by hemosiderin deposition in central nervous system and typically leads to neurological dysfunction and progressive irreversible symptoms. Multiple Sclerosis is most common demyelinating disease which usually courses with relapses and remissions but some patients can have a progressive course. Progression in MS patients is defined as a worsening of functional systems over one year.

We are presenting MS patient since 1994 who developed in last three years a progressive ataxia which was initially attributed to MS progression, nevertheless MRI showed hypointensities on cerebellum that led us to diagnose SS. Recognizing this entity is important because it could be a cause of pseudo progression in MS patients.

Objectives

We want to disclose the superficial siderosis as an unusual cause of pseudo-progression in patients affected by multiple sclerosis.

Methods

A 63 year-old woman with history of relapsing-remitting MS (RRMS) treated with Glatiramer acetate. She was stable until 2017, but since then she started to notice clumsiness of her both hands and difficulties to walk. She even had some falls because of unsteady gait.

Her Expanded Disability Status Scale (EDSS) passed from 2.0 to 4.5 due to worsening of cerebellar functional system and the using of a cane for walking. Over next three years she had progressive impairment of gait and coordination of all limbs. Sensorineural hearing loss of unknown cause was also diagnosed during this time. On last neurological examination she presented mild cerebellar dysarthria, moderate ataxia of all limbs, ataxic gait and need to walk with bilateral support. Other signs of the neurological examination were mild decrease of vibration and brisk reflexes on lower extremities. Currently her EDSS is 6.5

A cerebellar relapse was ruled out as cause of her symptoms because of progressive course, no recovery after steroids and no evidence of new T2 lesions on cerebellum. A RRMS turning into SPMS was initially accepted as responsible of her worsening.

Results

A comprehensive approach was performed, as there was an almost exclusive deterioration of the cerebellar functional system. So, a new brain MRI was requested and hemosiderin effect was seen along cerebellar folias. This finding was the key to diagnose superficial siderosis.

A neuroaxis MRI evaluation was done and there was no evidence of SS in other parts of CNS nor evidence of chronic bleeding that causes SS on cerebellum.

We proposed to initiate treatment with Deferiprone but the patient rejected to take it after we exposed lack of clear effectiveness. She is still being treated with Glatiramer acetate for MS.

Conclusions

Superficial siderosis can be a mimic of progression in patients affected by multiple sclerosis, that is why we recommend to take into account this entity in those patients with progressive worsening of walking secondary to exclusive affectation of cerebellar functional system.

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Genetics and Epigenetics Poster Presentation

P0517 - Circulating miRNA signatures in PPMS (ID 1309)

Abstract

Background

Primary progressive multiple sclerosis (PPMS) is a clinical subtype of MS characterized by the progressive accumulation of disability from onset. It is diagnosed in approximately 15% of people with multiple sclerosis (MS).

microRNAs (miRNAs) are small non-coding RNA molecules that participate in the regulation of gene expression. Their role in different diseases, including MS, is being studied.

Current disease-modifying therapies for MS as well as miRNA studies mainly focus on relapsing-remitting MS (RRMS), the most common subtype.

Objectives

The aim of this study was to identify and validate a differential profile of circulating miRNAs in PPMS patients compared to RRMS and controls with other neurological disease (OND) subjects in order to increase our knowledge of the biological processes involved in the different forms of the disease.

Methods

miRNAs were extracted from serum and cerebrospinal fluid (CSF) from a cohort of 111 patients (49 PPMS, 35 RRMS and 27 OND). In the identification phase, samples were analyzed using TaqMan OpenArray Human Advanced MicroRNA panels and in the validation phase, the quantification of the miRNAs was performed by qPCR. Differential expression was analyzed using the Kruskal-Wallis test with the normalized value of miRNAs.

Results

In the identification phase, 10 miRNAs showed differential expression in serum between some of the groups; while in CSF, miR-143-3p presented differential expression in PPMS group (p= 0.009), and let-7b-5p and miR-451a showed a tendency to be deregulated.

In serum samples, the validation phase showed miR-20a-5p overexpression in PPMS compared to controls, and miR-26a-5p among the forms of MS (p= 0.002 and p= 0.036, respectively). On the other hand, miR-142-5p was differentially expressed in RRMS compared to OND (p= 0.036).

In CSF, let-7b-5p and miR-143-3p presented significantly reduced levels in PPMS forms compared to OND (p= 0.029 and p= 0.039, respectively).

Conclusions

miR-20a-5p, miR-26a-5p, let-7b-5p and miR-143-3p present deregulation in PPMS versus RRMS and OND, indicating that they are involved in the pathophysiological mechanisms of PPMS forms. Further studies will be necessary to determine the role of these miRNAs in the development of the different forms of the disease.

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Genetics and Epigenetics Poster Presentation

P0519 - Differential expression of miRNAs in CSF of MS patients depending on their ethnic origin (ID 1312)

Presentation Number
P0519
Presentation Topic
Genetics and Epigenetics

Abstract

Background

Some studies have shown a more aggressive clinical course in multiple sclerosis (MS) patients of North African origin residing in Europe. It has been established that some genetic and environmental factors interact in a complex way by means of epigenetics to produce the pathology and the symptoms in MS. One of these epigenetic mechanisms is microRNAs (miRNAs), small non-coding RNA molecules that participate in the regulation of gene expression.

Objectives

The objective of this study was to identify the existence of a differential profile of circulating cerebrospinal fluid (CSF) miRNAs between individuals with MS based on their ethnic origin.

Methods

A cohort of 20 individuals was studied: 10 European origin (MS-E) and 10 North African origin individuals (MS-NA). MS-NA individuals were subclassified according to migration age (before or after 15 years old).

216 miRNAs were analyzed in CSF using TaqMan OpenArray Human Advanced MicroRNA panels. Differential expression of the normalized value of each miRNA was studied using the U Mann-Whitney test.

Results

When comparing the expression of miRNAs in CSF between MS-E and MS-NA, overexpression of miR-335-5p and miR-653-3p was observed in MS-NA (p= 0.008 and p= 0.027, respectively). Furthermore, two other miRNAs (miR-143-3p and miR-20a-5p) showed a tendency to be deregulated.

A sub-analysis was performed in which MS-NA was divided according to the age of migration. miR-145-5p, miR-150-5p and miR-653-3p showed significant differences between some of the 3 groups. Specifically, miR-150-5p, previously related to inflammation and MS in CSF, showed very low levels in MS-NA that migrated older than 15 years of age.

Conclusions

The results show the presence of a differential expression in miRNAs between MS patients according to their ethnic origin. In patients of North African origin who migrated at an early age, an overexpression of miRNAs clearly related to inflammation is observed.

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Genetics and Epigenetics Poster Presentation

P0524 - Importance of control group selection for differential miRNA profile studies (ID 1296)

Speakers
Presentation Number
P0524
Presentation Topic
Genetics and Epigenetics

Abstract

Background

BACKGROUND:

Cerebrospinal fluid (CSF) studies are necessary in neurological diseases, but the use of healthy controls (HC) is limited due to the ethical issues and difficulty in obtaining them. Usually, the control group corresponds to patients with other neurological diseases (OND).


Objectives

OBJECTIVES:

The main objective of this study was to evaluate the role of the control group in detecting altered miRNAs in multiple sclerosis (MS).

Methods

METHODS:

A panel of 216 CSF-specific miRNAs were analyzed using TaqMan Open Array Human Advanced MicroRNA in a cohort of 38 patients (16 primary progressive forms – PPMS, 9 HC, 13 OND).

HC corresponds to neurologically healthy patients with hip/knee impairment undergoing surgical intervention that requires spinal anaesthesia.

The pathologies presented by OND were: 6 individuals of vascular origin, 3 migraines, 1 conversion syndrome, 1 dementia, 1 dizziness, 1 cerebellar syndrome of non-inflammatory/infectious origin.

Results

RESULTS:

miR-1260a, miR-320a, and let-7c-5p showed differential expression, or a trend, in PPMS versus HC (p = 0.005; p = 0.021; p = 0.088, respectively). When making the same comparison with OND these significances were lost.

When analyzing deregulated miRNAs function, it was observed that let-7c-5p and miR-320a are involved in cerebral ischaemic and neurodegenerative disorders.

Conclusions

CONCLUSIONS:

Choosing the control group is crucial to identify altered miRNAs in a specific condition. If the objective is to identify metabolic pathways involved in a certain process, HC will be necessary since OND controls can share the altered pathways. On the other hand, when the objective is to identify biomarkers, the incorporation of OND into the analysis will be of great value to differentiate pathologies.

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Neuromyelitis Optica and Anti-MOG Disease Poster Presentation

P0699 - Clinical and radiological features of a hospital cohort of Neuromyelitis optica. (ID 324)

Speakers
Presentation Number
P0699
Presentation Topic
Neuromyelitis Optica and Anti-MOG Disease

Abstract

Background

Neuromyelitis optica spectrum disorders (NMOSD) are mostly relapsing autoimmune inflammatory disorders of the central nervous system. Hallmark features of NMOSD include acute attacks of bilateral or rapidly sequential optic neuritis or transverse myelitis. Attacks most often occur over days, with variable degrees of recovery over weeks to months

Other suggestive symptoms include episodes of intractable nausea, vomiting, hiccups, excessive daytime somnolence or narcolepsy, reversible posterior leukoencephalopathy syndrome, neuroendocrine disorders, and seizures

The discovery of AQP-4 antibodies supposed a breakthrough for understanding NMOSD. Recently, MOG antibodies have been also related to this entity. However, about 10-50% of NMOSD patients are still seronegative. These patients are a heterogeneous subgroup that may be associated with other autoantibodies

Objectives

To identify main clinical and radiological characteristics

To recognize differences between seropositive and seronegative NMOSD patients

To evaluate safety and effectiveness of Rituximab

Methods

We presented 12 patients diagnosed of NMOSD according revised consensus criteria published in 2015 at Unit of Neuroimmunology and Multiple Sclerosis Unit of Girona, Spain

The data were collected during the course of clinical care. We focused on medical history, neurologic symptoms, MRI features, CSF findings

Rituximab response was assessed using the annualized relapse rate (ARR)

Results

Disease-onset form: optic neuritis 7 (58,3%) 1 of them had bilateral optic neuritis; myelitis 4 (33,3%); brainstem syndrome 1 (8,3%)

Abnormal laboratory findings: 2 patients had positivity for lupus anticoagulant, 1 for TPO-Ab and 1 for ANAs

8 patients were seronegative NMOSD

6 patients (50%) had cognitive impairment

CSF findings: 8 patients had CSF abnormalities include pleocytosis and elevated protein levels. Oligoclonal bands were positive in 4 patients

4 patients were positive for antibodies: AQP-4= 2 / MOG= 2

MRI findings: 4 patients had brain MRI abnormalities that matched with NMOSD pattern, rest of patients had normal or unspecific MRI. Longitudinally extensive spinal cord lesions were observed in 7 patients. Cervical and thoracic segments were most affected

4 patients had positivity for other antibodies. 3 of them are seronegative NMOSD

Of 4 seropositive patients, 3 had cognitive impairment

Of 4 patients with presence of CSF oligoclonal bands, 3 were seronegative NMOSD

ARR before Rituximab: 1,25 and ARR after Rituximab: 0,27

No patient had serious adverse events after Rituximab treatment. Rituximab was discontinued in 1 patient due to an allergic reaction

Conclusions

Seronegative NMOSD has a prevalence up to 60% and it could be related with presence of other serum antibodies and with positivity for CSF oligoclonal bands

Cognitive impairment is frequent in NMOSD and can be more prevalent in seropositive patients

Rituximab is safe and effective to reduce ARR

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Neuropsychology and Cognition Poster Presentation

P0811 - Higher hippocampal functional connectivity in preclinical and initial stages of multiple sclerosis (ID 1724)

Abstract

Background

Memory impairment affects more than 50% of patients with multiple sclerosis (MS), strongly impacting their life quality. Previous studies have suggested a correlation between functional hippocampal alterations and episodic memory impairments in MS. Nevertheless, these studies are rarely focused on preclinical nor initial stages of the disease, essential to develop targeted interventions to prevent or delay memory impairment in MS.

Objectives

To investigate episodic memory performance and hippocampal functional connectivity abnormalities in the preclinical and initial stages of MS.

Methods

Cross-sectional study of 50 subjects: 30 healthy controls and 20 patients with clinical and radiological isolated syndrome (CIS/RIS) (n=13 and 7, respectively). Episodic memory capabilities were assessed with a modified version of Rey Auditory Verbal Learning Test (RAVLTm): introduction of two recognition trials in the five learning trials. Moreover, participants underwent a magnetic resonance imaging session on which resting-state sequences were acquired. Regression models were used to evaluate between-group differences in memory capabilities. Two-sample t-tests models were used to assess whole-brain differences in the seed-based functional connectivity (FC) of the bilateral hippocampus. All analysis were controlled for gender, age, educational level and presence of anxiety and/or depressive symptoms.

Results

No between-group differences emerged in the sum of the words of the learning trials (p=0.164), the delayed recall trial (p=0.193) nor the three recognition trials as measured by discriminability index (d’) (p=0.775, p=0.954, p=0.395, respectively) and Criterion Level (C) (p=0.860, p=0.864, p=0.858, respectively). Nevertheless, compared to controls, CIS/RIS showed higher FC in the hippocampi-right angular gyrus network (t= 5.18, p<0.001).

Conclusions

Prior any sign of episodic memory dysfunction in preclinical and initial stages of MS, higher FC in the hippocampi-right angular gyrus are detected. These findings could be explained as compensatory mechanism used by CIS/RIS to achieve the same performance in episodic memory task as healthy controls. At the same time, such FC increase could be an early sign of future episodic memory problems.

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Neuropsychology and Cognition Poster Presentation

P0812 - Hippocampal resting-state functional connectivity in Multiple Sclerosis subtypes (ID 1733)

Presentation Number
P0812
Presentation Topic
Neuropsychology and Cognition

Abstract

Background

Memory impairment is commonly found in multiple sclerosis (MS), presented in between 40 to 75% of patients. It is accepted that hippocampus plays a critical role in memory function therefore studying this brain structure is crucial to understand the nature of memory deficits. However, there is a lack of knowledge regarding how functional connectivity changes in memory-related brain regions, such as the hippocampus, exist between MS subtypes.

Objectives

To investigate hippocampal resting-state functional connectivity changes between MS subtypes and healthy controls, and associations with the presence of total white matter (WM) lesions.

Methods

30 healthy controls and 78 MS patients (34 relapsing-remitting (RRMS)), 24 primary or secondary progressive subtypes (PMS) and 20 clinical or radiological isolated syndrome (CIS/RIS)) underwent a magnetic resonance imaging session. Univariate ANOVA models in SPM12 were used to assess whole-brain differences in the seed-based functional connectivity (FC) of the bilateral hippocampus, between controls and MS subtypes. Regression models then assessed whether the FC strength in the identified hippocampal networks showed a significant association with total WM lesions.

Results

Mean total WM lesion volume was different among MS subtypes (F=18.493; p<0.001), with PMS showing the highest lesioned volume (16.32±14.09ml), followed by RRMS (8.93±9.46ml) and CIS/RIS (2.07±2.67ml). Compared to controls, both the PMS and RRMS showed lower FC in the hippocampi-right middle frontal gyrus network, while RRMS additionally showed lower FC with the rostral anterior cingulate cortex. Conversely, CIS/RIS showed higher FC in the hippocampi-right angular gyrus network. The lower FC in the hippocampi-right middle frontal gyrus network in PMS and RRMS was also significant compared with CIS/RIS, with PMS additionally showing lower FC in the hippocampi-dorsomedial frontal cortex. Finally, RRMS showed lower FC in the hippocampi-left insula network when directly compared to PMS. The strength of FC in the hippocampi-dorsomedial prefrontal cortex network was negatively associated with the total WM lesion volume (R2= 0.085, F= 6.76, p= 0.011) across the MS patients.

Conclusions

Hippocampal FC differences exist depending on MS subtypes, and the highest presence of total WM lesions impacts the FC with medial prefrontal cortex regions. Future studies are necessary to link such hippocampal changes with specific memory impairment.

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Pathogenesis – Immunology Poster Presentation

P0975 - Lipid-specific oligoclonal IgM bands condition age-related changes in multiple sclerosis (ID 1396)

Abstract

Background

Age has high influence on clinical course of chronic inflammatory diseases such as multiple sclerosis (MS). Lipid-specific oligoclonal IgM bands (LS-OCBM) in cerebrospinal fluid (CSF) of MS patients are biomarkers of high inflammatory disease. However, the relationship between both variables has not been fully studied.

Objectives

To explore age-related changes in CSF of MS patients leading to senescence and to study the role of LS-OCBM in this process.

Methods

A prospective cross-sectional study of 263 MS patients followed at Ramon y Cajal University Hospital, Madrid. Seventy-two showed (M+) and 191 (M-) lacked CSF LS-OCBM. We explored CSF immune cells, soluble mediators, microRNAs and clinical data.

Results

MS patients older than 45 years (O45) showed significant rises in CSF Programmed death ligand 1 (PD-L1; p=0.001) and T-cell immunoglobulin mucin-3 (TIM-3; p<0.0001), which induce lymphocyte tolerance, and in Chitinase 3-like-1 (p<0.0001) and Activin-A (p<0.0001), which lead to innate cell activation. This associated with low values of pro-inflammatory B cells and of Th17 lymphocytes. In addition, M- O45 patients experienced significant increases in miR-125b-5p (p=0.01) and miR-145-5p (p=0.02), two miRNA associated with immune senescence, an increase of let-7b-5p (p=0.01) that counteract innate-cell activation, a dramatic decrease of CSF lymphocytes (p<0.0001) and of NK cells (p=0.002) and increased serum anti-cytomegalovirus antibodies (p=0.009). However, M+ O45 patients exhibited a reduction of miR-204-5p (p=0.01), that induce innate-cell activation and increased CSF levels of superoxide dismutase (p=0.04) and isoprostane (p=0.03), markers of oxidative stress. These changes resulted in increased Multiple Sclerosis Severity Score (MSSS) on M+ O45 patients.

Conclusions

M- O45 MS patients showed inhibition of the intrathecal adaptive immune response and early immunosenescence. Conversely, M+ O45 MS patients displayed intrathecal innate cell activation and accelerated disability worsening. These data could be relevant for treating aged MS patients.

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Symptom Management Poster Presentation

P1092 - Effect of Dalfampridine on functional systems and its impact on Expanded Disability Status Scale (ID 281)

Speakers
Presentation Number
P1092
Presentation Topic
Symptom Management

Abstract

Background

Multiple sclerosis (MS) can cause progressive walking impairment that contributes to disability and reduced quality of life. Dalfampridine, a voltage-dependent potassium channel blocker, has been shown to improve walking in patients with MS, as demonstrated by an increase in walking speed.

Dalfampridine is approved as symptomatic treatment of impaired mobility in MS patients. Recently, it has been published dalfampridine could have an effect on other functional systems (FS) not directly related to ambulation.

Objectives

To demonstrate the dalfampridine effect on different FS.

To identify wether the impact on the different FS stabilizes the EDSS.

To establish correlations between different scales used to measure dalfampridine effectiveness and FS scores.

Methods

We collected 22 patients diagnosed of either relapsing-remitting, secondary progressive or primary progressive MS according Mc Donald´s criteria 2010 responsers to dalfampridine for at least one year.

Dalfampridine effectiveness was evaluated by Timed 25 foot-walk (T25-FW), Timed Up and GO (TUG), and Two minutes walk test (2MWT).

EDSS was performed every 3 months.

Median, interquartile ranges and p values were evaluated by Friedman test.

Results

- The mean of follow-up was 19,5 months (13 - 26)

- Outcomes on functional systems were:

Visual functions: at start treatment 0,0 (0.0 - 1.0); at 12 months 0,0 (0.0 - 0.0); at last visit: 0,0 (0.0 - 0.0) p= 0,069

Brainstem functions: at start treatment 0,0 (0.0 - 2.0); at 12 months 0,0 (0.0 - 2.0); at last visit: 0,0 (0.0 - 2.0) p= 0,368

Pyramidal functions: at start treatment 3,0 (2.0 - 3.0); at 12 months 3,0 (2.0 - 3.0); at last visit: 3,0 (2.0 - 3.0) p= 1,000

Cerebellar functions: at start treatment 2,0 (2.0 - 3.0); at 12 months 2,0 (1.0 - 2.0); at last visit: 2,0 (1.0 - 2.0) p= 0,670

Sensory functions: at start treatment 2,0 (2.0 - 3.0); at 12 months 2,0 (2.0 - 3.0); at last visit: 2,0 (2.0 - 3.0) p= 0,867

Bowel and Bladder functions: at start treatment 1,0 (0.0 - 1.0); at 12 months 1,0 (1.0 - 1.0); at last visit: 1,0 (1.0 - 1.0) p= 1,000

Cerebral functions: at start treatment 1,0 (0.0 - 2.0); at 12 months 0,0 (0.0 - 0.0); at last visit: 0,0 (0.0 - 0.0) p= 0,005

Ambulation score: at start treatment 6,0 (2.0 - 7.0); at 12 months 6,0 (3.0 - 7.0); at last visit: 6,0 (5.0 - 8.0) p= 0,323

- The EDSS mean at the start of dalfampridine was 5,61 (4.0 - 6.5), at 12 months 5,5 (3.5 - 7.0) p= 0,339 and at the last visit 5,45 (2.0 - 7.0) p= 0,441.

- There was a negative correlation between sphincter and sensory functions and 2MWT.

Conclusions

We could obtain a relevant effect of dalfampridine on cerebral functions measured over more than a year. Nonetheless, we can not conclude if this outcome is directly related with an effect over cognition or it is related with improvement of fatigue and depression.

EDSS remained stable over more than a year in dalfampridine responsers.

We can not explain why patients who are responsers to dalfampridine had worsening of sphincter and sensory functions at the same time.

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Presenter Of 1 Presentation

Genetics and Epigenetics Poster Presentation

P0524 - Importance of control group selection for differential miRNA profile studies (ID 1296)

Speakers
Presentation Number
P0524
Presentation Topic
Genetics and Epigenetics

Abstract

Background

BACKGROUND:

Cerebrospinal fluid (CSF) studies are necessary in neurological diseases, but the use of healthy controls (HC) is limited due to the ethical issues and difficulty in obtaining them. Usually, the control group corresponds to patients with other neurological diseases (OND).


Objectives

OBJECTIVES:

The main objective of this study was to evaluate the role of the control group in detecting altered miRNAs in multiple sclerosis (MS).

Methods

METHODS:

A panel of 216 CSF-specific miRNAs were analyzed using TaqMan Open Array Human Advanced MicroRNA in a cohort of 38 patients (16 primary progressive forms – PPMS, 9 HC, 13 OND).

HC corresponds to neurologically healthy patients with hip/knee impairment undergoing surgical intervention that requires spinal anaesthesia.

The pathologies presented by OND were: 6 individuals of vascular origin, 3 migraines, 1 conversion syndrome, 1 dementia, 1 dizziness, 1 cerebellar syndrome of non-inflammatory/infectious origin.

Results

RESULTS:

miR-1260a, miR-320a, and let-7c-5p showed differential expression, or a trend, in PPMS versus HC (p = 0.005; p = 0.021; p = 0.088, respectively). When making the same comparison with OND these significances were lost.

When analyzing deregulated miRNAs function, it was observed that let-7c-5p and miR-320a are involved in cerebral ischaemic and neurodegenerative disorders.

Conclusions

CONCLUSIONS:

Choosing the control group is crucial to identify altered miRNAs in a specific condition. If the objective is to identify metabolic pathways involved in a certain process, HC will be necessary since OND controls can share the altered pathways. On the other hand, when the objective is to identify biomarkers, the incorporation of OND into the analysis will be of great value to differentiate pathologies.

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