Beta-Interferon Treatment Reduces Human Herpesvirus-6 Viral Load in Multiple Sclerosis Relapses but Not in Remission

Risk of cancer in individuals with Lynch-like syndrome and their families: a systematic review

BACKGROUND

Lynch-like syndrome (LLS) tumors have similar clinicopathological features to Lynch syndrome (LS) tumors but have no identifiable pathogenic germline mismatch repair gene variant. However, cancer risks in LLS patients and first-degree relatives (FDRs) are not well defined.

METHODS

To clarify LLS-associated cancer risks, a systematic review of all studies examining all cancer risks in LLS was performed. Searching of Medline, Embase, Pubmed, Cochrane and CINAHL databases and reference/citation checking identified relevant studies published between January 1, 1980 and February 11, 2021. Joanna Briggs Institute Appraisal Tools assessed the risk of bias.

RESULTS

Six studies (five cohort/one cross-sectional) were eligible for study inclusion. One study found no difference in colorectal cancer (CRC) incidence between LLS and LS patients or CRC risks at aged 70 years. Three studies found CRC incidence in LLS FDRs was higher than the general population but lower than LS FDRs. Two studies showed no difference in CRC diagnosis age between LLS patients and LS patients. Endometrial cancer risks in LLS patients were higher than the general population but lower than LS patients.

CONCLUSION

Evidence of elevated CRC risks in LLS patients and FDRs supports increased colonoscopy surveillance strategies for LLS patients and FDRs in line with current recommendations for LS. Due to heterogeneity amongst LLS populations, extended intervals between screening may be advised for low-risk families. Studies to resolve the molecular characterization and definition of LLS are needed to clarify cancer risks associated with LLS which in turn may individualize surveillance strategies for LLS patients and families.

Cumulative Roles for Epstein-Barr Virus, Human Endogenous Retroviruses, and Human Herpes Virus-6 in Driving an Inflammatory Cascade Underlying MS Pathogenesis

Roles for viral infections and aberrant immune responses in driving localized neuroinflammation and neurodegeneration in multiple sclerosis (MS) are the focus of intense research. Epstein-Barr virus (EBV), as a persistent and frequently reactivating virus with major immunogenic influences and a near 100% epidemiological association with MS, is considered to play a leading role in MS pathogenesis, triggering localized inflammation near or within the central nervous system (CNS). This triggering may occur directly via viral products (RNA and protein) and/or indirectly via antigenic mimicry involving B-cells, T-cells and cytokine-activated astrocytes and microglia cells damaging the myelin sheath of neurons. The genetic MS-risk factor HLA-DR2b (DRB1*1501β, DRA1*0101α) may contribute to aberrant EBV antigen-presentation and anti-EBV reactivity but also to mimicry-induced autoimmune responses characteristic of MS. A central role is proposed for inflammatory EBER1, EBV-miRNA and LMP1 containing exosomes secreted by viable reactivating EBV+ B-cells and repetitive release of EBNA1-DNA complexes from apoptotic EBV+ B-cells, forming reactive immune complexes with EBNA1-IgG and complement. This may be accompanied by cytokine- or EBV-induced expression of human endogenous retrovirus-W/-K (HERV-W/-K) elements and possibly by activation of human herpesvirus-6A (HHV-6A) in early-stage CNS lesions, each contributing to an inflammatory cascade causing the relapsing-remitting neuro-inflammatory and/or progressive features characteristic of MS. Elimination of EBV-carrying B-cells by antibody- and EBV-specific T-cell therapy may hold the promise of reducing EBV activity in the CNS, thereby limiting CNS inflammation, MS symptoms and possibly reversing disease. Other approaches targeting HHV-6 and HERV-W and limiting inflammatory kinase-signaling to treat MS are also being tested with promising results. This article presents an overview of the evidence that EBV, HHV-6, and HERV-W may have a pathogenic role in initiating and promoting MS and possible approaches to mitigate development of the disease.

Merkel cell polyomavirus DNA in the blood of patients with neurological diseases and healthy controls

Aim: Merkel cell polyomavirus (MCPyV) is the etiological agent of Merkel cell carcinoma. Its genome has been detected in anatomic districts from healthy and ill subjects. Data regarding the MCPyV DNAemia in neurological patients are lacking. Materials & methods: Blood was obtained from 129 neurological patients and 181 controls (HIV positive or negative). Real-time polymerase chain reaction (Q-PCR) was conducted to quantify MCPyV loads in blood specimens. Results: MCPyV DNA was detected in 17.1% of cases and 11.0% of controls in <1% of cells. No association between MCPyV DNA presence and HIV status was observed. Conclusion: Blood cells may be a reservoir for MCPyV. The presence of MCPyV genome in blood of healthy subjects might be relevant for transfusion medicine.

Synergetic and antagonistic effects of combined calcitriol and interferon-β treatment on cytokine production by stimulated PBMCs

BACKGROUND

We evaluated the effects of calcitriol and interferon-β on in vitro PBMC cytokine production from a cohort of 22 healthy adults not on medication.

METHODS

PBMCs were incubated with calcitriol and/or 100 or 400IU interferon-β or nothing, followed by stimulation with concanavalin A.

RESULTS

When combined, calcitriol and interferon-β appeared to potentiate the effects of one another on reducing IL-6. Calcitriol significantly reduced the production of IL-2, IL-4, IL-6, and IFN-γ, while interferon-β significantly reduced production of IL-6 and TNF-α, and increased IL-10.

DISCUSSION

This is the first study to evaluate the effects of combined calcitriol and interferon-β on cytokine production in PBMCs in vitro, demonstrating novel synergetic effects.

EBV & HHV6 reactivation is infrequent and not associated with MS clinical course

BACKGROUND

Among the environmental factors associated with multiple sclerosis (MS) causation, some of the strongest associations are with Epstein-Barr virus (EBV), and to a lesser extent human herpesvirus 6 (HHV6). Associations with clinical course are less conclusive, however.

METHODS

We evaluated serum anti-EBV-EA-R IgG and anti-HHV6 IgM, and EBV and HHV6 viral load (VL) for their associations with relapse, disability, and progression in disability in a prospective cohort of 198 participants with clinically definite MS.

RESULTS

Anti-EBV-EA-R IgG was detected in 81.8% of cases at study entry, and titers remained essentially unchanged during the study. Anti-HHV6 IgM was detected in only one participant, and EBV-VL (29%) and HHV6-VL (1.8%) were detected in a minority of samples, and where detected levels were low. Our previously demonstrated association between anti-HHV6 IgG and relapse hazard was not affected by adjustment for parameters of reactivation. We found no evidence that any of the viral markers were associated with disability or progression in disability. In relation to relapse, only EBV-VL was positively associated, although this was strongly influenced by a single individual.

CONCLUSION

Using a prospective cohort design, we found no convincing evidence that reactivation parameters of EBV or HHV6 were associated with subsequent MS relapse hazard or progression in disability, confirming previous findings, and indicating that herpesvirus reactivation is not an important driver of relapse or disability in this established MS population.

Anti-human herpesvirus 6A/B IgG correlates with relapses and progression in multiple sclerosis

OBJECTIVE

To analyze the titers of the IgG and IgM antibodies against human herpesvirus 6A/B (HHV-6A/B) in multiple sclerosis (MS) patients treated with different disease modified therapies (DMTs) along two-years of follow-up.

METHODS

We collected 2163 serum samples from 596 MS; for 301 MS patients a 2-years follow-up was performed. Serum samples of 337 healthy controls were also analyzed. Anti-HHV-6A/B IgG and IgM were analyzed by ELISA (Panbio).

RESULTS

We found that 129/187 (69.0%) MS patients with a decrease of the anti-HHV-6A/B IgG titers after 2-years with DMTs were free of relapses and progression vs. 46/113 (40.7%) of MS patients with an increase of the anti-HHV-6A/B IgG titers (p = 0.0000015); the higher significance was found for natalizumab. Furthermore, we found that anti-HHV-6A/B IgG titers reached their highest value two weeks before the relapse (p = 0.0142), while the anti-HHV-6A/B IgM titers reached their highest value one month before the relapse (p = 0.0344).

CONCLUSION

The measurement of the anti-HHV-6A/B IgG titers could be a good biomarker of clinical response to the different DMTs. The increase of the anti-HHV-6A/B IgG and IgM titers predicts the upcoming clinical relapses. However, further longitudinal studies are needed to validate these results.

Incidence of human herpesvirus 6 in clinical samples from Swedish patients with demyelinating diseases

BACKGROUND

Human herpesvirus 6 (HHV-6) has been reported to be associated with multiple sclerosis (MS) and Guillain-Barré syndrome (GBS).

METHODS

We analyzed cell-free HHV-6 DNA as an indication of active infection in the peripheral blood and cerebrospinal fluid (CSF) of Swedish patients with GBS, patients with chronic inflammatory demyelinating polyradiculoneuropathy, treatment-naïve patients with possible MS, interferon-β treated MS patients [with or without neutralizing antibodies (NAbs)], and control patients with headache.

RESULTS

One of 14 GBS patients and one of eight patients with chronic inflammatory demyelinating polyradiculoneuropathy were positive for HHV-6 DNA in serum. Of the 27 treatment-naïve possible MS patients, two were positive in plasma and one in CSF. HHV-6 DNA was detected in the serum of three of 79 NAb+ patients and one of 102 NAb-interferon-β treated MS patients. HHV-6 DNA could not be detected in the plasma or CSF of any of the 33 controls, although the differences were not statistically significant.

CONCLUSION

Our results do not suggest active HHV-6 infection to be a common phenomenon in any of the patient groups studied.

Anti-HHV-6 IgG titer significantly predicts subsequent relapse risk in multiple sclerosis

BACKGROUND

Some of the strongest associations with MS onset are for human herpesviruses, particularly Epstein-Barr virus (EBV) and human herpesvirus 6 (HHV-6). Their role in MS clinical course is less clear, however.

METHODS

Prospective cohort of 198 persons with clinically definite MS, followed 2002-5, and serum samples obtained from all subjects at study entry to measure anti-HHV-6 and anti-EBV (Epstein-Barr nuclear antigen [EBNA] and viral capsid antigen [VCA]) IgG titers. Association with relapse evaluated using survival analysis; association with disability/progression evaluated using linear regression or multilevel mixed-effects linear regression.

RESULTS

For the 145 persons with relapsing-remitting MS followed beyond one review, anti-HHV-6 IgG titer was positively associated with the hazard of relapse with a dose-dependent trend (p = 0.003), not affected by adjustment for anti-EBV IgG titers, neither of which were independently associated with relapse. There was no significant association between anti-human herpesvirus IgG titers and baseline-measured disability scores, or change in disability scores; however, anti-HHV-6 IgG titers were 2.8 times higher among progressive-course females than progressive-course males.

DISCUSSION

These findings suggest that, in addition to a potential etiological role in MS, HHV-6 infection or the immune response to HHV-6 antigens may have an effect on the risk of MS relapses and possibly on progressive courses of MS. The observed effect was directly related to anti-HHV-6 IgG titers and may indicate that either HHV-6 infection or factors associated with an altered humoral immune response to HHV-6 may have an effect on MS clinical course. Anti-HHV-6 IgG titer may be a useful prognostic factor in relapsing-remitting MS clinical course.

Association between human herpesvirus 6 and occurrence of multiple sclerosis among Jordanian patients

OBJECTIVES

Multiple sclerosis (MS) is hypothesized to be caused by an infectious agent that initiates an autoimmune reaction. Among the infectious agents linked to MS is human herpesvirus 6 (HHV-6). Due to the high occurrence of MS among Jordanian population and the deficiency of MS studies in Jordan, the prevalence of HHV-6 in sera and cerebrospinal fluids (CSFs) of 36 MS patients was investigated.

MATERIALS AND METHODS

To increase the sensitivity of detection, nested polymerase chain reaction was utilized.

RESULTS

Although we were able to detect HHV-6 DNA in serum samples of 26% MS patients, no significant difference was found when compared to control individuals. In addition, lack of association between MS and presence of viral DNA in CSF samples was observed. Even within the analyzed MS patient population, an association of HHV-6 and MS in terms of gender, type of diagnosis, symptoms and disease score was not identified among Jordanian patients.

CONCLUSIONS

Although these results indicate lack of apparent association between HHV-6 to MS among Jordanian patients, heterogeneity related to genetic polymorphism as well as geographical distribution of the disease and of pathogens may be of significance.

MHC2TA rs4774C and HHV-6A active replication in multiple sclerosis patients

BACKGROUND AND PURPOSE

In a previous report, a strong gene-environment interaction between human herpesvirus 6A (HHV6A) active replication and MHC2TA rs4774C was demonstrated. The objectives of this study were: (i) to reappraise the association that was found in the previous study; (ii) to evaluate if MS patients with minor allele C and HHV-6A active infection had different clinical behavior; and (iii) to analyze the possible association of MHC2TA rs4774C with Epstein-Barr virus (EBV).

METHODS

A total of 149 MS patients were analyzed both at the MHC2TA locus and by HHV-6A status in serum. We studied a G/C polymorphism (rs4774) by a TaqMan Assay-on-Demand. HHV-6A genomes in serum were evaluated by quantitative PCR. A control group of 562 healthy Spanish individuals was included for comparative purposes in the genetic analyses. A battery of clinical data was collected for all the MS patients included in the study.

RESULTS

(i) MHC2TA/HHV-6A interaction: we found the same strong association of the rs4774C allele with HHV-6A active replication than in the previous study (P = 0.0001). (ii)

CLINICAL DATA

the two main statistical significant differences for MS patients with HHV-6A active infection and minor allele C were: (a) a significant number of them were not free of progression (EDSS = 0) 2 years after the diagnosis (P = 0.01); (b) only a third of them responded to interferon beta treatment (P = 0.05).

CONCLUSIONS

This study has verified previous results about the strong gene-environment interaction between HHV6A active replication and MHC2TA rs4774C. Furthermore, a different clinical behavior for MS patients with HHV-6A active infection and minor allele C was found.

JC virus viremia in interferon-beta -treated and untreated Italian multiple sclerosis patients and healthy controls

Following the development of progressive multifocal leukoencephalopathy (PML) in two multiple sclerosis (MS) patients treated with natalizumab and interferon-beta (IFNbeta), a possible correlation between JC virus (JCV), the etiological agent of PML, and MS has received heightened interest. In particular, attention has focused on assessing whether IFNbeta treatment could affect the replication of JCV and thus its frequency in the peripheral blood of MS patients and whether the presence of JCV DNA in peripheral blood could be a predictive marker of the risk of developing PML. In order to answer to these questions, peripheral blood samples were collected from 59 INFbeta-treated, 39 untreated relapsing-remitting MS patients, and 98 healthy controls (HCs) and JCV DNA levels were determined and quantified by means of a real-time polymerase chain reaction (Q-PCR) assay. Overall, no differences were found in the presence or viral load of JCV DNA of MS patients and the HCs, but JCV DNA was significantly less frequent in the peripheral blood of IFNbeta-treated patients (13.6%) compared to the untreated MS patients (46.1%) and the healthy controls (28.6%). These results suggest that the presence of JCV in the blood of MS patients cannot be considered as a marker or a risk factor for PML development. In addition, they indicate that treatment with INFbeta can lead to the reduction of presence of the JCV genome in the peripheral blood of MS patients and, thus, that this drug probably does not increase the risk of PML in MS patients treated with IFNbeta.

Interferon-beta treatment and active replication of the JC virus in relapsing-remitting multiple sclerosis patients

We analyzed the effect of beta-interferon (beta-IFN) treatment over the active replication of JC virus (JCV) through the evaluation of JCV DNA prevalence and viral load in peripheral blood mononuclear cells (PBMCs) and serum samples, and mRNA prevalence and viral load, in relapsing-remitting multiple sclerosis (RRMS) patients. DNA extracted from PBMCs and serum, and mRNA extracted from PBMCs were analyzed in 146 RRMS patients (73 treated with beta-IFN, and 73 untreated patients), and 73 matched healthy blood donors for the presence of JCV genomes by quantitative real-time PCR assay. We found the same DNA prevalence in PBMC samples in RRMS patients treated with beta-IFN and in untreated ones: 6.8% (5/73). When we analyzed the viral active replication in both groups through the analysis of DNA prevalence in serum samples and the mRNA extracted from PBMCs, we did not find any positive sample. Regarding the viral load of those positive samples, we did not find any statistical significant difference between treated and untreated RRMS patients: 28.6 +/- 7.2 and 32.3 +/- 8.4 copies/microg of DNA, respectively. These results lead us to conclude that beta-IFN treatment in monotherapy has not any effect on JCV active replication.

Biological and clinical advances in human herpesvirus-6 and -7 research

Since its isolation more than 20 years ago, human herpesvirus (HHV)-6 has been considered an opportunistic pathogen whose infection and/or reactivation is associated with diseases such as roseola, organ transplant anomalies and central nervous system disorders. The lack of relevant animal models, standardized diagnostic reagents and specific anti-HHV-6 drugs has impaired our ability to prove a causal relationship between the presence of this virus and the development of many diseases. Unless such models and reagents are developed and clinical trials performed, speculations on the role for this virus in various pathologies will continue to grow. In this review, recent biological, clinical and epidemiological research advances in the HHV-6 field as well as that of its closest relative, HHV-7, will be presented. Additionally, priority research areas that will help move the field forward are discussed.

Mechanisms of action for treatments in multiple sclerosis: Does a heterogeneous disease demand a multi-targeted therapeutic approach?

The etiology of multiple sclerosis (MS) is incompletely understood, and evidence suggests there may be more than one underlying cause in this disorder. Furthermore, this complex and heterogeneous autoimmune disease shows a high degree of clinical variability between patients. Therefore, in the absence of a single therapeutic target for MS, it is difficult to apply conventional drug design strategies in the search for new treatments. We review the potential mechanisms of action of several effective therapies for MS that are currently available or in development. The effects of each treatment are described in terms of their actions on key processes in a five-step model of MS pathogenesis. Conventional immunosuppressants targeting intracellular ligands (e.g. mitoxantrone) have broad cytotoxic effects on B cells, T cells, and macrophages. This suppresses the pathogenic immune response in MS with high efficacy but is also associated with high toxicity, limiting the long-term use of these agents. Monoclonal antibodies (e.g. natalizumab and alemtuzumab) are a new generation of immunosuppressants that act on immune-cell surface ligands. These agents have narrower immunosuppressive actions and different safety profiles compared with conventional immunosuppressants. Immunomodulators (interferon-beta and glatiramer acetate), which shift the immune balance toward an anti-inflammatory response, are at the frontline of treatments for MS. Immunomodulators have targeted actions on the immune system, but affect a greater number of immunopathogenic processes than monoclonal antibodies. Given the inherent heterogeneity of MS, such treatments, which act at many levels of the disease, may achieve the best clinical results. Using our understanding of the interplay between mechanism of action and clinical effects in MS therapies may help us to better design and select new treatments for the future.

Co-purification of soluble membrane cofactor protein (CD46) and human herpesvirus 6 variant A genome in serum from multiple sclerosis patients

The association of human herpesvirus 6 (HHV-6) and multiple sclerosis (MS) has been supported by several immunological and molecular studies. Recently, membrane cofactor protein (CD46) has been identified as the cellular receptor for the A and B variants of HHV-6. Elevated levels of soluble CD46 (sCD46) have been reported in the serum and CSF of MS patients. The aim of this study was to investigate a possible correlation between elevated levels of soluble CD46 and the presence of serum HHV-6 DNA in MS patients. An immunoaffinity column comprised of immobilized monoclonal antibodies to CD46 was developed to isolate sCD46 from cell free body fluids of MS patients and controls. After immunoaffinity purification, DNA was extracted from anti-CD46 column eluates and subjected to PCR amplification. Of the 42 MS samples tested, 4 serum samples were HHV-6 positive, 3 of which were typed as HHV-6A. The co-purification of sCD46 and HHV-6 DNA from MS sera indicates that HHV-6 is tightly connected to its receptor, CD46, in the serum of MS patients.