Human interferon regulatory factor 5 homologous epitopes of Epstein-Barr virus and Mycobacterium avium subsp. paratuberculosis induce a specific humoral and cellular immune response in multiple sclerosis patients.

BACKGROUND: A large number of reports indicate the association of Epstein-Barr virus (EBV), and Mycobacterium avium subsp. paratuberculosis (MAP) with multiple sclerosis (MS). OBJECTIVE: To gain a better understanding of the role of these two pathogens, we investigated the host response induced by selected antigenic peptides. METHODS: We examined both humoral and cell-mediated responses against peptides deriving from EBV tegument protein BOLF1, the MAP_4027 and the human interferon regulatory factor 5 (IRF5424-434) homolog in several MS patients and healthy controls (HCs). RESULTS: Antibodies against these peptides were highly prevalent in MS patients compared to HCs. Concerning MS patients, BOLF1305-320, MAP_402718-32 and IRF5424-434 peptides were able to induce mainly Th1-related cytokines secretion, whereas Th2-related cytokines were down-regulated. Flow cytometry analyses performed on a subset of MS patients highlighted that these peptides were capable of inducing the release of pro-inflammatory cytokines: IFN-γ and TNF-α by CD4(+) and CD8(+) T lymphocytes, and IL-6 and TNF-α by CD14(+) monocyte cells. CONCLUSION: Our data demonstrated that both EBV and MAP epitopes elicit a consistent humoral response in MS patients compared to HCs, and that the aforementioned peptides are able to induce a T-cell-mediated response that is MS correlated.

Proinsulin and MAP3865c homologous epitopes are a target of antibody response in new-onset type 1 diabetes children from continental Italy.

Mycobacterium avium subspecies paratuberculosis (MAP) asymptomatic infection is speculated to play a role in type 1 diabetes (T1D) among Sardinian subjects. Data obtained analyzing a pediatric population from mainland Italy lends support to the hypothesis, which envisions MAP as an environmental factor at play in T1D pathogenesis. Aiming to investigate the likelihood of cross-recognition between linear determinants shared by self (proinsulin) and non-self (MAP) proteins, 59 children with new onset T1D and 60 healthy controls (HCs) from continental Italy were enrolled in the study. Serum samples were subjected to indirect enzyme-linked immunosorbent assay (ELISA) for the presence of antibodies (Abs) toward four homologues MAP/proinsulin epitopes. The rate of MAP infection (42.4% in T1D children and 5% in HCs; p < 0.0001) was estimated searching for Abs against MAP specific protein MptD. The homologous MAP2404c70-85 and proinsulin (PI)46-61 peptides were recognized by 42.4 and 39% of new-onset T1D children and only in 5% of HCs (AUC = 0.76, AUC = 0.7, p < 0.0001); whereas the prevalence of Abs against MAP 1,4-α-gbp157-173 and PI64-80 peptides was 45.7 and 49.1% in new-onset T1D children, respectively, compared with 3.3% of HCs (AUC = 0.74 and p < 0.0001 in both). Pre-incubation of MAP Ab-positive sera with proinsulin peptides was able to block the binding to the correspondent MAP epitopes, thus showing that Abs against these homologous peptides are cross-reactive. MAP/Proinsulin Ab mediated cross-recognition, most likely via molecular mimicry, maybe a factor in accelerating and/or initiating T1D in MAP-infected children. Indeed, it is known that anti-proinsulin and anti-Insulin autoantibodies are the earliest to appear.

Natalizumab inhibits the expression of human endogenous retroviruses of the W family in multiple sclerosis patients: a longitudinal cohort study.

BACKGROUND: Several viruses were reported as co-factors triggering the pathogenesis of multiple sclerosis (MS), including the endogenous retroviruses of the HERV-W family, that were also proposed as biomarkers of disease progression and therapy outcome. OBJECTIVE: The objective of this article is to clarify whether in MS patients treatment with natalizumab has effects on MSRV/syncytin-1/HERV-W expression and the possible relationship with disease outcome. METHODS: Peripheral blood mononuclear cells were collected from 22 patients with relapsing-remitting disease, at entry and after three, six and 12 months of treatment with natalizumab. The cell subpopulations and the expression of MSRVenv/syncytin-1/HERV-Wenv were analyzed by flow cytometry and by discriminatory env-specific RT-PCR assays. RESULTS: By flow cytometry the relative amounts of T, NK and monocyte subpopulations were shown to remain fairly constant. A relative increase of B lymphocytes was observed at three to six months (p = 0.033). The MSRVenv and syncitin-1 transcripts were reduced at six to 12 months of therapy (p = 0.0001). Accordingly, at month 12, the plasma-membrane levels of the HERV-Wenv protein were reduced (p = 0.0001). B cells, NK and monocytes but not T cells expressed the HERV-Wenv protein. None of the patients relapsed during therapy. CONCLUSION: Effective therapy with natalizumab downregulates MSRV/syncytin-1/HERV-W expression.

Prevalence of KRAS, BRAF, and PIK3CA somatic mutations in patients with colorectal carcinoma may vary in the same population: clues from Sardinia.

BACKGROUND: Role of KRAS, BRAF and PIK3CA mutations in pathogenesis of colorectal cancer (CRC) has been recently investigated worldwide. In this population-based study, we evaluated the incidence rates and distribution of such somatic mutations in genetically isolated population from Sardinia. METHODS: From April 2009 to July 2011, formalin-fixed paraffin-embedded tissues (N = 478) were prospectively collected from Sardinian CRC patients at clinics across the entire island. Genomic DNA was isolated from tissue sections and screened for mutations in KRAS, BRAF, and PIK3CA genes by automated DNA sequencing. RESULTS: Overall, KRAS tumour mutation rate was 30% (145/478 positive cases). Distribution of mutation carriers was surprisingly different within the island: 87/204 (43%) in North Sardinia vs. 58/274 (21%) in Middle-South Sardinia (p<0.001). Among 384 CRC cases whose DNA was available, only one (0.3%) patient carried a mutation in BRAF gene; PIK3CA was found mutated in 67 (17%) patients. A significant inverse distribution of PIK3CA mutation rates was observed within Sardinian population: 19/183 (10%) cases from northern vs. 48/201 (24%) cases from central-southern island (p<0.001). This heterogeneity in frequencies of KRAS/PIK3CA somatic mutations is consistent with already-reported discrepancies in distribution of germline mutations for other malignancies within Sardinian population. Preliminary clinical evaluation of 118 KRAS wild-type patients undergoing anti-EGFR-based treatment indicated lack of role for PIK3CA in predicting response to therapy. CONCLUSIONS: Our findings support the hypothesis that differences in patients' origins and related genetic backgrounds may contribute to even determine the incidence rate of somatic mutations in candidate cancer genes.

Molecular Characterization of Severe Acute Respiratory Syndrome Coronavirus 2 Isolates From Central Inner Sardinia.

BACKGROUND: The SARS-CoV-2 pandemic stimulated an outstanding global sequencing effort, which allowed to monitor viral circulation and evolution. Nuoro province (Sardinia, Italy), characterized by a relatively isolated geographical location and a low population density, was severely hit and displayed a high incidence of infection. METHODS: Amplicon approach Next Generation Sequencing and subsequent variant calling in 92 respiratory samples from SARS-CoV-2 infected patients involved in infection clusters from March 2020 to May 2021. RESULTS: Phylogenetic analysis displayed a coherent distribution of sequences in terms of lineage and temporal evolution of pandemic. Circulating lineage/clade characterization highlighted a growing diversity over time, with an increasingly growing number of mutations and variability of spike and nucleocapsid proteins, while viral RdRp appeared to be more conserved. A total of 384 different mutations were detected, of which 196 were missense and 147 synonymous ones. Mapping mutations along the viral genome showed an irregular distribution in key genes. S gene was the most mutated gene with missense and synonymous variants frequencies of 58.8 and 23.5%, respectively. Mutation rates were similar for the S and N genes with one mutation every ∼788 nucleotides and every ∼712 nucleotides, respectively. Nsp12 gene appeared to be more conserved, with one mutation every ∼1,270 nucleotides. The frequency of variant Y144F in the spike protein deviated from global values with higher prevalence of this mutation in the island. CONCLUSION: The analysis of the 92 viral genome highlighted evolution over time and identified which mutations are more widespread than others. The high number of sequences also permits the identification of subclusters that are characterized by subtle differences, not only in terms of lineage, which may be used to reconstruct transmission clusters. The disclosure of viral genetic diversity and timely identification of new variants is a useful tool to guide public health intervention measures.

Early Diffusion of SARS-CoV-2 Infection in the Inner Area of the Italian Sardinia Island.

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been responsible for the coronavirus disease 2019 (COVID-19) pandemic, which started as a severe pneumonia outbreak in Wuhan, China, in December 2019. Italy has been the first European country affected by the pandemic, registering a total of 300,363 cases and 35,741 deaths until September 24, 2020. The geographical distribution of SARS-CoV-2 in Italy during early 2020 has not been homogeneous, including regions severely affected as well as administrative areas being only slightly interested by the infection. Among the latter, Sardinia represents one of the lowest incidence areas likely due to its insular nature. METHODS: Next-generation sequencing of a small number of complete viral genomes from clinical samples and their virologic and phylogenetic characterization was performed. RESULTS: We provide a first overview of the SARS-CoV-2 genomic diversity in Sardinia in the early phase of the March-May 2020 pandemic based on viral genomes isolated in the most inner regional hospital of the island. Our analysis revealed a remarkable genetic diversity in local SARS-CoV-2 viral genomes, showing the presence of at least four different clusters that can be distinguished by specific amino acid substitutions. Based on epidemiological information, these sequences can be linked to at least eight different clusters of infection, four of which likely originates from imported cases. In addition, the presence of amino acid substitutions that were not previously reported in Italian patients has been observed, asking for further investigations in a wider population to assess their prevalence and dynamics of emergence during the pandemic. CONCLUSION: The present study provides a snapshot of the initial phases of the SARS-CoV-2 infection in inner area of the Sardinia Island, showing an unexpected genomic diversity.

Inhibition of multiple-sclerosis-associated retrovirus as biomarker of interferon therapy.

The authors performed a longitudinal evaluation of multiple sclerosis (MS) patients, during 1 year of therapy with interferon-beta (IFN-beta), by clinical examination and detection of presence in the blood and viral load of MS-associated retrovirus (MSRV), by MSRVenv-specific, fully quantitative, real time reverse transcriptase-polymerase chain reaction (RT-PCR). MSRV load in the blood was directly related to MS duration and fell below detection limits within 3 months of IFN therapy; one patient had strong progression, accompanied by total MSRV rescue. These findings suggest that evaluation of plasmatic MSRV could be considered the first prognostic marker for the individual patient, to monitor disease progression and therapy outcome.

p73 Interacts with human immunodeficiency virus type 1 Tat in astrocytic cells and prevents its acetylation on lysine 28.

Human immunodeficiency virus type 1 (HIV-1) Tat is a potent transcriptional activator of the HIV-1 promoter and also has the ability to modulate a number of cellular regulatory circuits including apoptosis. Tat exerts its effects through interaction with viral as well as cellular proteins. Here, we studied the influence of p73, a protein that is implicated in apoptosis and cell cycle control, on Tat functions in the central nervous system. Protein interaction studies using immunoprecipitation followed by Western blot and glutathione S-transferase pull-down assays demonstrated the association of Tat with p73. Tat bound to the N-terminal region of p73 spanning amino acids 1 to 120, and this interaction required the cysteine-rich domain (amino acids 30 to 40) of Tat. Association of p73 with Tat prevented the acetylation of Tat on lysine 28 by PCAF. Functional studies including RNA interference showed that p73 inhibited Tat stimulation of the HIV-1 promoter. Furthermore, p73 prevented the interaction of Tat with cyclin T1 in vitro but not in vivo. These findings suggest possible new therapeutic approaches, using p73, for Tat-mediated AIDS pathogenesis.

Differential expression of miRNA 155 and miRNA 146a in Parkinson's disease patients.

Parkinson's disease is a neurodegenerative disorder and its etiology is unknown, numerous studies show how different environmental factors can influence the development of disease. miRNAs are involved in several pathologies and their dysregulation contribute to different pathologies, also in neurodegenerative such as Parkinson's disease, Alzheimer's disease, Huntington's disease and Amyotrophic lateral sclerosis. In this study, we profiled the expression of different candidate miRNAs: miR-155, miR-26a, miR-146a, and miR132, in PBMCs of L-dopa treated Parkinson patients and unaffected controls (HCs).We investigated the expression of miRNAs by RT-real time PCR, the results were subjected to statistical analysis. miRNA-155-5p was generally up-regulated in PD patients compared to HCs whereas miRNA-146a-5p was down-regulated in PD patients in comparison to HCs. It is interesting to point out that the expression of miR-155-5p was modified by levodopa treatment, in fact a down-regulation of miR-155-5p in PD patients with the highest dosage was observed. In conclusion, miRNA 155 could not only be a promising target for the anti-inflammatory therapy in PD but also a good candidate as a disease progression biomarker. The role of levodopa in modulating the levels of miRNA 155 requires further studies.

Tubulin-mediated binding of human immunodeficiency virus-1 Tat to the cytoskeleton causes proteasomal-dependent degradation of microtubule-associated protein 2 and neuronal damage.

One of the hallmarks of human immunodeficiency virus (HIV)-1 associated pathology in the CNS is deterioration of neuronal processes. Although there is mounting evidence of neuronal toxicity and cell death induced by the HIV-1 transactivating factor Tat, the molecular events linked directly to its detrimental effect on neuronal cells remain unclear. In this study, we used rat embryonic cortical neurons and demonstrated that Tat causes rapid degradation of microtubule-associated protein 2 (MAP2) and the collapse of cytoskeletal filaments. The mechanism of Tat action on MAP2 stability involved Tat-mediated translocation of the proteasome to the site of microtubule filaments. Immunohistochemical analysis of clinical samples from patients with HIV encephalopathy further revealed a significant decrease in MAP2 with predominant cytoplasmic 20S in cortical neurons near microglial nodules. These findings indicate a novel mechanism for the action of Tat on neuronal cells. It involves proteasome-mediated MAP2 degradation and may account for the loss of MAP2 and neuronal damage observed in the brain of AIDS patients with neurological dysfunctions.

Antibody response against HERV-W env surface peptides differentiates multiple sclerosis and neuromyelitis optica spectrum disorder.

Background: A specific humoral immune response against HERV-W envelope surface (env-su) glycoprotein antigens has been reported in serum of patients with multiple sclerosis (MS). However, it has not been evaluated to date in patients with neuromyelitis optica spectrum disorder (NMOSD). Objective: The objective of this paper is to investigate whether antibody (Ab) response against HERV-W env-su antigenic peptides differs between NMOSD and MS. Methods: Serum samples were collected from 36 patients with NMOSD, 36 patients with MS and 36 healthy control individuals (HCs). An indirect ELISA was set up to detect specific Abs against HERV-W env-su peptides. Results: Our data showed that two antigenic peptides, particularly HERV-Wenv93-108 and HERV-Wenv248-262, were statistically significantly present only in serum of MS compared to NMOSD and HCs. Thus, the specific humoral immune response against HERV-W env-su glycoprotein antigens found in MS is widely missing in NMOSD. Conclusion: Increased circulating serum levels of these HERV-W Abs may be suitable as additional biomarkers to better differentiate MS from NMOSD.

Epstein Barr Virus and Mycobacterium avium subsp. paratuberculosis peptides are recognized in sera and cerebrospinal fluid of MS patients.

Mycobacterium avium subsp. paratuberculosis (MAP) and Epstein-Barr virus (EBV) epitopes elicit a consistent humoral response in serum of multiple sclerosis patients, but the cross reactivity against the homologous myelin basic protein (MBP) and human interferon regulatory factor 5 (IRF5) has not been searched within the Cerebral Spinal Fluid (CSF). We evaluated in sera and CSF of patients with MS and with other neurological diseases (OND) the humoral response against EBV/MAP peptides and the IRF5/MBP. Our data showed that EBV and MAP peptides are able to induce a specific humoral immune response in MS patients compared to OND controls both in serum and in CSF. An intrathecal specific synthesis of IgG against MBP and their EBV and MAP homologous as indicated by the antibody index was observed in MS patients. The humoral response against EBV, MAP, MBP and IRF5 was significantly higher in MS patients compared to OND both in serum and in CSF. The higher presence of antibodies against MBP and their MAP and EBV homologous in CSF during relapses suggests a possible role of the pathogens in enhancing inflammation.

Is there a role for Mycobacterium avium subspecies paratuberculosis in Parkinson's disease?

In Parkinson's disease (PD) ZnT proteins play an important role. Zinc is a co-factor of numerous enzymes and stabilizes the tertiary structure of several proteins. Nothing is known about previous infections mediated by Mycobacterium avium subsp. paratuberculosis (MAP). We evaluated if a previous infection with MAP could induce the production of antibodies that cross-reacted with the Znt homologous antigenic peptides associated to Parkinson. The humoral response toward MAP3865c peptides, ZnT3 and ZnT10 was evaluated. The hypothesis of cross-reactivity needs to be confirmed; we have observed the presence of MAP in PD patients by PCR, positivity to MAP3865c peptides, therefore MAP infection but not cross-reaction with human homologous Znt proteins.

Type 1 Diabetes at-risk children highly recognize Mycobacterium avium subspecies paratuberculosis epitopes homologous to human Znt8 and Proinsulin.

Mycobacterium avium subspecies paratuberculosis (MAP) has been previously associated to T1D as a putative environmental agent triggering or accelerating the disease in Sardinian and Italian populations. Our aim was to investigate the role of MAP in T1D development by evaluating levels of antibodies directed against MAP epitopes and their human homologs corresponding to ZnT8 and proinsulin (PI) in 54 T1D at-risk children from mainland Italy and 42 healthy controls (HCs). A higher prevalence was detected for MAP/ZnT8 pairs (62,96% T1D vs. 7,14% HCs; p < 0.0001) compared to MAP/PI epitopes (22,22% T1D vs. 9,52% HCs) and decreasing trends were observed upon time-point analyses for most peptides. Similarly, classical ZnT8 Abs and GADA decreased in a time-dependent manner, whereas IAA titers increased by 12%. Responses in 0-9 year-old children were stronger than in 10-18 age group (75% vs. 69,1%; p < 0.04). Younger age, female sex and concomitant autoimmune disorders contributed to a stronger seroreactivity suggesting a possible implication of MAP in multiple autoimmune syndrome. Cross-reactivity of the homologous epitopes was reflected by a high correlation coefficient (r(2) > 0.8) and a pairwise overlap of positivity (>83% for MAP/ZnT8).

Serum BAFF levels, Methypredsinolone therapy, Epstein-Barr Virus and Mycobacterium avium subsp. paratuberculosis infection in Multiple Sclerosis patients.

Elevated B lymphocyte activating factor BAFF levels have been reported in multiple sclerosis (MS) patients; moreover, disease-modifying treatments (DMT) have shown to influence blood BAFF levels in MS patients, although the significance of these changes is still controversial. In addition, BAFF levels were reported increased during infectious diseases. In our study, we wanted to investigate on the serum BAFF concentrations correlated to the antibody response against Mycobacterium avium subspecies paratuberculosis (MAP), Epstein-Barr virus (EBV) and their human homologous epitopes in MS and in patients affected with other neurological diseases (OND), divided in Inflammatory Neurological Diseases (IND), Non Inflammatory Neurological Diseases (NIND) and Undetermined Neurological Diseases (UND), in comparison to healthy controls (HCs). Our results confirmed a statistically significant high BAFF levels in MS and IND patients in comparison to HCs but not NIND and UND patients. Interestingly, BAFF levels were inversely proportional to antibodies level against EBV and MAP peptides and the BAFF levels significantly decreased in MS patients after methylprednisolone therapy. These results implicate that lower circulating BAFF concentrations were present in MS patients with humoral response against MAP and EBV. In conclusion MS patients with no IgGs against EBV and MAP may support the hypothesis that elevated blood BAFF levels could be associated with a more stable disease.

Soluble BAFF Level Is Not Correlated to Mycobacterium avium Subspecies Paratuberculosis Antibodies and Increases After Interferon-ß Therapy in Multiple Sclerosis Patients.

B cells are being recognized as one of the major players in the pathogenesis of multiple sclerosis (MS). The B cell activating factor (BAFF) system plays an essential role in B cell homeostasis and function in the periphery. Mycobacterium avium subspecies paratuberculosis (MAP) has been previously associated to MS in Sardinia. Antibodies against a MAP surface protein, MAP_2694, have been found significantly associated to MS patients, and this response was modified by interferon-ß therapy. Increased BAFF levels following IFN-ß therapy have been also described in MS patients. In this study, we evaluated whether soluble BAFF levels are comparable in men and women affected by MS and performed a correlation of the reported BAFF increase in MS patients under IFN-ß therapy with changes of humoral response against MAP_2694. For these reasons, we investigated 44 MS patients before and after IFN-ß therapy. A significant difference of BAFF levels was found between men and women with MS; moreover, we confirmed that IFN-ß therapy strongly induces BAFF serum levels, but this was not related to the modification of immunological response against MAP_2694. In conclusion, our study highlights that IFN-ß therapy induces the potent B cell survival factor BAFF without alterations of the humoral immune response against MAP.

Natalizumab Therapy Modulates miR-155, miR-26a and Proinflammatory Cytokine Expression in MS Patients.

MicroRNAs fine-tune the regulation of Th1/Th17 lymphocyte subsets in multiple sclerosis. We investigated the expression of miRNAs (previously associated with mycobacterial and viral infections) in MS patients and healthy donors (HD) following 6 months natalizumab therapy. In addition, Th1/Th17 cytokines and the presence of anti-EBNA1/VCA IgG in MS patients with different pattern of miRNA expression have been evaluated. MiR-155, miR-26a, miR-132, miR-146a and Th1/Th17 cytokines expression was detected by RT-real time PCR; moreover anti-EBNA1 and VCA IgG titres were measured by ELISA. We observed an up-regulation of miR-155 (p value = 0.009) and miR-132 (p value = 0.04) in MS patients compared to HD. In MS patients, IL-17a (p = 0.037), IFN γ (p = 0.012) and TNFα (p = 0.015) but not IL-6 were over-expressed compared to HD. Two different miRNAs patterns associated to the expression of different cytokines were observed in the MS cohort. Moreover, a down-regulation of miR-155 and miR-26a was seen in MS patients during and after natalizumab therapy. MS patients that over-expressed miR-155 showed a higher EBNA1 IgG titer than MS patients with high levels of miR-26a. In conclusions the expression of particular miRNAs modulates the pro-inflammatory cytokine expression and the humoral response against EBV and this expression is natalizumab regulated.

Natalizumab modulates the humoral response against HERV-Wenv73-88 in a follow-up study of Multiple Sclerosis patients.

Multiple Sclerosis (MS) is a heterogeneous disorder of the central nervous system (CNS) that begins as an inflammatory autoimmune disorder mediated by auto-reactive lymphocyte followed by microglial activation and chronic degeneration. The etiology of Multiple Sclerosis (MS) is unknown but several data support the hypothesis of possible infectious agents which may act as a trigger for the pathogenic cascade. Human endogenous retrovirus (HERV-W/MSRV), Epstein Barr Virus (EBV) and Mycobacterium avium ss. paratuberculosis (MAP) have been associated to Multiple Sclerosis. In this study, we evaluated the humoral response against different peptides: the human endogenous retrovirus HERV-Wenv73-88, MAP106c121-132 from MAP, EBNA1 400-413 from EBV and the homologous human peptide MBP85-98 in a cohort of MS patients treated with natalizumab. Results showed a statistically significant difference in the response against the HERV-W peptide in MS patients after two years of natalizumab treatment.

Lack of humoral response against Helicobacter pylori peptides homologous to human ZnT8 in Hashimoto's thyroiditis patients.

INTRODUCTION: The Helicobacter pylori (HP) reinfection rate seems to be higher in developing countries than in developed ones. An increased seroprevalence of HP has also been reported in patients with type 1 diabetes (T1D) and Hashimoto's thyroiditis (HT). Mycobacterium avium subsp. paratuberculosis (MAP) has been linked to both T1D and HT. Quite a few lines of evidence indicate that autoantibodies against several epitopes belonging to human zinc transporter 8 (ZnT8) cross-recognize the homologous MAP3865c epitopes in both T1D and HT patients. HP may play a role in HT disease, most likely acting through a molecular mimicry mechanism that targets ZnT8 as reported for MAP and the two autoimmune diseases. METHODOLOGY: An enzyme-linked immunosorbent assay (ELISA) has been developed for the detection of antibodies against several epitopes deriving from HP proteins, which are highly homologous to the immunodominant ZnT8 peptides previously identified: ZnT8178-186 and ZnT8186-194. RESULTS: None of the HP peptides tested were significantly recognized when the humoral responses of 92 HT patients and 91 healthy volunteers were analyzed. CONCLUSIONS: These findings do not support a triggering role for HP (through ZnT8 mimicking) in HT. If a molecular mimicry phenomenon is taking place, it involves a different self-antigen. Moreover, the negative outcome of the experiments performed stresses the fact that sharing stretches of sequence homology is relevant, but not enough to trigger an antibody-mediated cross-recognition.

Epitopes of HERV-Wenv induce antigen-specific humoral immunity in multiple sclerosis patients.

To verify the serological response mounted against antigenic peptides from HERV-Wenv protein, we analyzed 80 multiple sclerosis (MS) serum samples, 27 of which were re-analyzed after a 6-month follow-up IFN-ß therapy, and 73 healthy controls. Indirect ELISAs were carried out to detect antibodies specific for all the synthetic peptides derived from HERV-Wenv. Two antigenic peptides, HERV-Wenv93-108 (31.25%, p<0.0001) and HERV-Wenv248-262 (15%, p=0.02), were highly recognized by MS patients' antibodies when compared to healthy subjects. Moreover, antibody titer against these two peptides slightly decreased after six months of IFN-ß-based therapy.