Seroreactivity to human T cell leukemia/lymphoma virus type 1 and related retroviruses in multiple sclerosis patients from Denmark and the Faroes

A total of 40 multiple sclerosis (MS) patients from Denmark and 10 from the Faroes were examined for antibodies with affinity to human T cell leukemia/lymphoma virus type 1 (HTLV-I) and human immunodeficiency virus type 1 and 2 (HIV-1 and HIV-2). Using ELISA, MS patients and a group of healthy controls did not differ significantly in their reactivities to HTLV-I. However, elevated reactivities were recorded with 5 MS sera, whereas only 2 of the sera from the controls produced highly values. Ten patients with other neurological diseases all seemed to exhibit low reactivity in HTLV-I ELISA. The reactivities of 2 MS sera decreased considerably by absorption with an HTLV-I lysate. In immunofluorescence assay, two other MS sera reacted with HTLV-I transformed cell lines as well as with non-infected cells. Examined by Western blotting (WB), a single MS serum produced a distinct HTLV-I p19 band. With ELISA for detection of HIV-1 and HIV-2 antibodies, 2 MS sera exhibited borderline reactions. Further examination of these two sera by WB revealed weak reactivities against p24 and p53 of HIV-1. One the whole, the present observations do not suggest that a putative MS retrovirus would be closely related with HTLV-I, HIV-1 or HIV-2.     

Absence of HTLV-1 related sequences in MS from high prevalence areas in Western Norway

In Western Norway, long-term follow up epidemiological studies have revealed significant increases in the incidence and prevalence rates of multiple sclerosis (MS) in stable populations, indicating the impact of exogenous factors. In this study 183 MS patients and 102 controls from high prevalence areas in Western Norway were investigated for human T-lymphotropic virus type I (HTLV-1) related sequences by polymerase chain reaction. Using primers targeting the gag , pol and env genes in the HTLV-1 provirus genome, no amplification products were detected in the 183 MS patients or 102 controls. The results strongly suggest that neither HTLV-1 nor a closely related retrovirus participate in the aetiology of MS.     

A C77G point mutation in CD45 exon 4, which is associated with the development of multiple sclerosis and increased susceptibility to HIV-1 infection, is undetectable in Japanese population

HTLV-1 associated myelopathy/tropical spastic paraparesis (HAM/TSP) is one outcome of Human T-cell lymphotropic virus type 1 (HTLV-1) infection. It remains unknown why the majority of infected people remain healthy whereas only approximately 2-3% develop disease. Recently, heterozygous state of CD45 exon 4 mutation (C77C wild type and C77G mutant) was reported to be associated with development of multiple sclerosis in German patients and increased susceptibility to HIV-1 infection in the United Kingdom. To investigate whether this mutation is associated with the development of HAM/TSP, we studied a group of 164 HAM/TSP patients and 108 asymptomatic HTLV-1 carriers in Kagoshima (HTLV-1 endemic area in Southern Japan) by using PCR-RFLP and subsequent direct sequencing analysis. All 272 subjects showed homozygosity in the CD45 exon 4, suggesting that this mutation is absent or very rare in Japanese population.     

Development of a pan-retrovirus detection system for multiple sclerosis studies

Introduction - Although recent claims implicating HTLV-1 in multiple sclerosis (MS) have been refuted, several reports suggest that another, hitherto uncharacterised, retrovirus may be involved. We have developed and applied a novel PCR-based strategy to explore this possibility. Methods - Degenerate oligonucleotides were used in a semi-nested format to amplify, from reverse-transcribed RNA, a region of the pol gene which is well conserved amongst all known retroviruses. Results - The 'pan-retrovirus' detection system was shown to be capable of detecting diverse retroviruses including human lentivirus, human oncovirus, simian D-type virus and murine oncovirus. The 'pan-retrovirus' technique identified a novel retroviral sequence, designated MSRV-cpol, in the serum of an MS patient and also in purified virions from MS patient-derived tissue cultures. Sequence comparisons suggest that in the pol gene MSRV is related (˜75% homology) to the endogenous retroviral element ERV9. Conclusion - These findings lend further support to the concept of retroviral involvement in MS.     

Multiple sclerosis, tropical spastic paraparesis and HTLV-1 infection in Afro-Caribbean patients in the United Kingdom.

Forty four consecutive patients of Afro-Caribbean origin resident in the United Kingdom (UK) were studied, based on a provisional diagnosis of myelopathy of unknown cause, tropical spastic paraparesis (TSP) or multiple sclerosis (MS). Of 30 patients with progressive paraparesis 27 had serum antibodies to HTLV-1 and were classified as having TSP. Fourteen patients fulfilled the criteria for MS and none of 12 tested had HTLV-1 antibodies. All the TSP patients and nine of those with MS were born in the West Indies. Five of the West Indianborn MS patients had migrated to the UK after adolescence but the duration of residence in the UK before symptoms of MS developed was similar to those born in the UK (average 18 years). The features that differentiated MS from TSP patients, apart from HTLV-1 status, included clinical evidence of cranial nerve involvement, more extensive abnormalities on the brain and cervical cord MRI and asymmetry of the VEP latency increase, all of which were more frequent in the MS group. Of the three patients without a diagnosis one, born in the UK, had marked abnormalities on MRI of the brain indistinguishable from those seen in MS.     

Antiretroviral antibodies: implications for schizophrenia, schizophrenia spectrum disorders, and bipolar disorder.

BACKGROUND: Some retroviral antigens share structural homology within a group of related retroviruses. It is possible that antibodies directed against one virus may cross-react with antigens from a different virus in the group. METHODS: Using this principle, the human immunodeficiency virus 1 (HIV-1) Western blot assay was used as an available source of human retroviral antigens to screen serum samples from an archived collection to ascertain whether there was an association between serum antiretroviral antibodies and mental illnesses. RESULTS: A statistically significant proportion (28/54, 52%) of patients suffering from psychiatric disorders had serum antibodies that recognized at least one antigen present on the blot, culminating in indeterminate HIV-1 tests. The majority of the reactive samples were directed against the HIV-1 group antigens p24 and p17. These findings contrast with those of nonpsychiatric patients, who had 4/16 (25%) indeterminate blots. CONCLUSIONS: The results suggest exposure to retroviral antigens related to those of HIV-1 in subpopulations of schizophrenic, schizophrenic spectrum disorder, and bipolar disorder patients.     

Retroviruses and multiple sclerosis. I. Analysis of seroreactivity by western blot and radioimmune assay

We were unable to identify an antibody to either HTLV-I or HIV-1 in patients with multiple sclerosis (MS) by ELISA, by radioimmune assay, or by radioimmune precipitation techniques. Immunoblot studies for HTLV-I-specific antibodies revealed faintly reactive bands in 2 of 44 MS patients but not in patients with other neurologic diseases. We did not find seroreactivity to HIV-1 or to the distantly related retrovirus, caprine arthritis encephalitis virus (CAEV). These findings suggest that MS is not related to infection by human retroviruses with antigenic similarity to HTLV-I, HIV-1, or CAEV.     

Particle-associated retroviral RNA and tandem RGH/HERV-W copies on human chromosome 7q: possible components of a 'chain-reaction' triggered by infectious agents in multiple sclerosis?

Different groups have observed retrovirus particle (RVP) production in cell cultures from patients with multiple sclerosis (MS). This in vitro production appeared relatively specific for MS versus healthy controls, but was likely to be enhanced or activated by infectious triggers such as Herpesviruses (e.g. HSV, EBV). Independent molecular analysis of retroviral RNA associated with RVP revealed two different genetic families of endogenous retroviral elements (HERV): MSRV/HERV-W and RGH/HERV-H. Interestingly, these sequences were detected by mutually exclusive primers in RT - PCR amplifications. Surprisingly, these two HERV families both contain an ancestral proviral copy inserted in chromosome 7q21-22 region at about 1 kb of distance of each other. Another HERV-W proviral sequence is located within a T-cell alpha-delta receptor (TCR) gene in chromosome 14q11.2 region. Interestingly, these two regions correspond to genetic loci previously identified as potentially associated with 'multigenic' susceptibility to MS and TCR alpha chain genetic determinants have been reported to be statistically associated with MS. A plausible role for infectious agents triggering a co-activation of the chromosome 7q HERV tandem (replicative retrovirus and/or other virus and/or intracellular bacteria) and, eventually, other HERV copies, is discussed. The role of particular HERV polymorphism and the production of pathogenic molecules (gliotoxin and superantigen) possibly associated with retroviral expression are also evoked. An integrative concept of pathogenic 'chain-reaction' in MS involving several step-specific pathogenic 'agents' and 'products' somewhat interacting with particular genetic elements would federate most partial data obtained on MS, including retroviral expression.     

Use of immunoreactive synthetic HTLV-1 peptides in the search for antibody reactivity in multiple sclerosis

The possible association between multiple sclerosis (MS) and antibodies to human T-cell lymphotropic virus type 1 (HTLV-1) was studied. Five synthetic and highly immunoreactive HTLV-1 peptides, four from the envelope (env) region and one from the core (gag) region, were used in an indirect enzyme-linked immunosorbent assay (ELISA). Presence of HTLV-1-specific antibodies in paired serum and cerebrospinal fluid (CSF) samples from 41 MS patients were investigated. No antibody reactivity was demonstrable in samples from 40 of them, whereas one reacted in one serum sample against the gag-peptide. Serum and CSF specimens from 15 with other neurologic diseases (OND), and negative control specimens, i.e. serum and CSF from 9 non-neurologic controls and CSF from 9 healthy controls, did not demonstrate any reactivity in the peptide-ELISAs. Our results do not support involvement of HTLV-1 infection in the etiology of MS.     

NMO-IgG and Devic's neuromyelitis optica: a French experience

BACKGROUND: A serum autoantibody biomarker, NMO-IgG has been recently described in patients with Devic's neuromyelitis optica (DNMO) and so called ;high-risk' patients for this disease. Our objectives were to replicate the test and to assess its usefulness. METHODS: Indirect immunofluorescence with a substrate of adult rat cerebellum and midbrain was used to identify the distinctive NMO-IgG staining pattern. We tested masked sera from 26 patients with DNMO (group 1), 21 patients with idiopathic acute transverse myelitis (ATM) (group 2), 21 patients with bilateral and/or recurrent idiopathic optic neuritis (group 3), 52 patients with classical multiple sclerosis (MS) (group 4), 36 patients with HTLV-1 infection (group 5) and 7 patients with miscellaneous disorders (group 6). RESULTS: We identified a vascular staining pattern typical of NMO-IgG. This particular staining was observed in 14/26 samples in group 1, 7/21 in group 2 (positive only in longitudinally extensive acute transverse myelitis: 7/13), 4/21 in group 3 (with bilateral loss of vision in all seropositive cases), 5/52 in group 4 (none of them suggestive of DNMO), 0/36 in group 5 and 0/7 in group 6. Sensitivity of the test was 54% considering detection of DNMO (group 1), and specificity was respectively 94% and 90% when considering groups 4, 5 and 6 altogether or group 4 of MS patients only. CONCLUSION: Detection of NMO-IgG is contributory to the distinction of DNMO and 'DNMO high-risk' syndromes from MS. This test may allow earlier diagnosis and help therapeutic decisions.     

HTLV-1 antibodies in serum and cerebrospinal fluid in tropical spastic paraparesis in Brazil

HTLV-1 antibodies were investigated in serum and in CSF of 150 patients with neurologic disorders mainly myelopathies. The patients were considered into three groups according to the possible relationship of their disease to the presence of HTLV-1 antibodies: no relationship risk (control group), occasional risk group, and possible risk group. In this latter are 56 patients with crural spastic paraparesis or paraplegia of unknown etiology (SP). HTLV-1 antibodies were tested by the passive particle-agglutination method for anti-ATLA antibody detection. The search was negative in all patients of the control group, and positive (serum and/or CSF) in 16.5% of the patients from the second group and in 55.4% of the SP patients group. Clinical patterns in SP cases with HTLV-1 antibodies were those of tropical spastic paraparesis (TSP). CSF patterns considered (cytology, protein content and gamma-globulins rate) were different between TSP group with HTLV-1 antibodies in CSF and SP group with no HTLV-1 antibodies detection either in serum or in CSF. The difference was significant. Results of this investigation confirm the high incidence of TSP in Brazil, and bring additional indication for searching HTLV-1 antibodies in the CSF.     

Antibody against EBV in CSF from HIV-1 and HTLV-I infected patients

We have measured the levels of antibody (ab) against different Epstein-Barr virus (EBV) antigens in 10 AIDS patients, 7 HTLV-1 associated myelopathy/tropical spastic paraparesis (HAM/TSP) patients and 20 control subjects. We found comparable serum levels of anti-EBV ab between AIDS patients, HAM/TSP patients and control subjects. By contrast, anti-EBV ab were present in the large majority of CSF from AIDS patients (70%) and HAM/TSP patients (60%) but only in 15% of control group. Our results support a synergistic role of EBV in retroviral infections of the central nervous system.     

Modulation of T cell responses in HTLV-1 carriers and in patients with myelopathy associated with HTLV-1

OBJECTIVE: Human T lymphotropic virus-type 1 (HTLV-1) activates the immune system leading to a persistent and exacerbated T-cell response with increased production of IFN-gamma and TNF-alpha. Overproduction of pro-inflammatory cytokines is correlated with the development of HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP), although some HTLV-1 carriers also show high levels of these cytokines. In this study, the ability of regulatory cytokines and cytokine antagonists to inhibit spontaneous IFN-gamma production was investigated. METHOD: IFN-gamma levels were measured by ELISA before and after addition of cytokines or anti-cytokines. RESULTS: Addition of IL-10 significantly reduced spontaneous IFN-gamma synthesis in cell cultures from HTLV-1 carriers, while no differences were observed in HAM/TSP patients. There was also a tendency to decreased IFN-gamma levels in cell cultures from HTLV-1 carriers with exogenous addition of TGF-beta. In paired analysis, neutralization of IL-2 significantly decreased IFN-gamma production in HTLV-1 carriers but not in HAM/TSP patients. Neutralization of IL-15 was less effective than neutralization of IL-2 in modulating IFN-gamma production. In HTLV-1 carriers, anti-IL-2 and simultaneous addition of anti-IL-2 and anti-IL-15 decreased IFN-gamma synthesis by 46 and 64%, respectively, whereas in patients with HAM/TSP simultaneous neutralization of both anti-cytokines only decrease IFN-gamma levels by 27%. CONCLUSIONS: Although a large proportion of HTLV-1 carriers produced high levels of pro-inflammatory cytokines similar to those observed in HAM/TSP patients, immune response can be downregulated by cytokines or cytokine antagonists in most HTLV-1 carriers. This modulation can be an important step in the prevention of tissue damage and progression from the HTLV-1 carrier state to HAM/TSP.     

High ratio of HTLV-1-infected cells in HTLV-1 associated myelopathy (HAM)

Sixteen patients with HTLV-1 associated myelopathy (HAM) were examined for the presence of HTLV-1 provirus genome by Southern blot analysis of genomic DNA from peripheral blood mononuclear (PBM) cells. Random integration of the provirus was detected in 14 of 16 HAM patients. By contrast, the provirus genome could not be detected in 6 non-HAM HTLV-1 carriers, HAM patients were found to have significantly higher antibody titer to HTLV-1 in the sera compared with carriers. These features of HAM patients, i.e., detectable levels of provirus integration in PBM cells and high antibody titer to HTLV-1 in the sera, were noted in 2 wives of HAM patients with neurological signs and abnormalities. High anti-HTLV-1 antibody titer and detection of the provirus genome by Southern hybridizations may be useful for screening subclinical HAM cases and elucidating pathogenesis.     

ApaI polymorphism of vitamin D receptor gene is associated with susceptibility to HTLV-1-associated myelopathy/tropical spastic paraparesis in HTLV-1 infected individuals

HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) is one outcome of human T-cell lymphotropic virus type-1 (HTLV-1) infection. It remains unknown why the majority of infected people remain healthy, whereas only approximately 2-3% of infected individuals develop the disease. The active form of vitamin D has immunomodulatory effects, and allelic variants of the vitamin D receptor (VDR) appear to be associated with differential susceptibility to several infectious diseases. To investigate whether VDR single nucleotide polymorphisms (SNPs) are associated with the development of HAM/TSP, we studied four VDR SNPs in a group of 207 HAM/TSP patients and 224 asymptomatic HTLV-1 seropositive carriers (HCs) in Kagoshima, Japan, by using PCR-RFLP analysis. We found that ApaI polymorphism of VDR is associated with the risk of HAM/TSP, although this polymorphism did not affect the provirus load of HTLV-1 in either HAM/TSP patients or HCs.     

Multiple sclerosis-like illness occurring with human immunodeficiency virus infection

We describe seven men with a neurologic disease clinically indistinguishable from multiple sclerosis occurring in association with seropositivity for the human immunodeficiency virus, type 1 (HIV-1). Histopathology of the CNS obtained in three patients (2 by brain biopsy, 1 at autopsy) was consistent with MS. The neurologic symptoms preceded the onset of clinically evident immunosuppression in all patients. In three men, HIV-1 seropositivity was demonstrated concomitantly or within 3 months of the onset of their neurologic disease. In the others, features of MS preceded the demonstration of HIV-1 seropositivity by 41 months, 59 months, 11 years, and 18 years, respectively. Despite the superimposition of varying degrees of cellular immunodeficiency associated with HIV-1 infection, six of these men continued to experience relapsing neurologic symptoms.     

Increased frequency of CD4+T cells expressing fractalkine receptor CX3CR1 in patients with HTLV-1 associated myelopathy/tropical spastic paraparesis (HAM/TSP), but its AIDS susceptible polymorphisms are not associated with the disease

To investigate whether fractalkine receptor CX3CR1 polymorphisms that have been associated with rapid progression to AIDS among HIV-1 positive individuals also affects the risk of human T cell lymphotropic virus type 1 (HTLV-1) associated myelopathy/tropical spastic paraparesis (HAM/TSP), we compared the allele frequencies of V249I and T280M between 233 HAM/TSP patients and 213 HTLV-1 seropositive asymptomatic carriers (HCs). Although the frequency and absolute number of peripheral blood CX3CR1+CD4+T cells were significantly increased in HAM/TSP patients compared to HCs and uninfected controls independent of HTLV-1 trans-activator protein Tax, we could not observe any association between the two polymorphisms and the risk of HAM/TSP in our cohort.     

Search for an HTLV-I-like retrovirus in patients with MS by enzymatic DNA amplification

A retroviral etiology to MS has been sought for some time, so far reports of retroviral presence have not been confirmed by other groups. DNA was isolated from peripheral blood mononuclear cells from 67 patients with MS and brain capillaries from six patients with MS. Enzymatic amplification by the polymerase chain reaction was conducted with ten primersets homologous to highly conserved HTLV-I/HTLV-II genetic sequences at stringent and non-stringent annealing conditions. No HTLV I/II related DNA fragments were seen judging from hybridization to an HTLV-I probe, even at relaxed conditions. The present study does not support a role for a HTLV-I-like virus in MS.     

Polymerase chain reaction analysis for specific HTLV-1 sequences from cerebrospinal fluid and peripheral blood cells in Sardinian multiple sclerosis patients.

Using polymerase chain reaction and specific primers, we found no gag and env sequences of HTLV-1 in DNA samples from peripheral blood mononuclear cells of 26 multiple sclerosis (MS) patients with relapsing-remitting, relapsing-progressive and progressive course from onset of the disease, and from 8 patients affected with other neurological diseases (OND). A Positive signal for the gag region was found in DNA samples from cerebrospinal fluid mononuclear cells (CSFMC) of 6/17 (27.3%) MS patients (either with relapsing-remitting, or relapsing-progressive and progressive course from onset of the disease), and in 2/11 (18.2%) CSFMC OND samples. Positive hybridization for the env sequence was evident in 2/11 (18.2%) CSFMC from OND and none of MS samples. The finding of positive hybridization for gag and env sequences in a few samples of CSFMC may be related to the presence in the CSF of a great number of activated cells, which could express cross-reacting sequences of endogenous retrovirus.