Alterations in cell-mediated immune response in subacute sclerosing panencephalitis

Immune alterations in subacute sclerosing panencephalitis reflect an incompetent response to eliminate the measles virus

In subacute sclerosing panencephalitis (SSPE) the persistence of measles virus (MeV) may be related to the altered immune response. In this study, cytokine responses of lymphocytes and monocytes were evaluated in SSPE compared to controls with non-inflammatory (NICON) and inflammatory (ICON) diseases. Patients with SSPE (n = 120), 78 patients with ICON and 63 patients with NICON were included in this study. Phenotypes of peripheral blood mononuclear cells (PBMC) have been analyzed by flow cytometry. CD3 and CD28, and S. aureus Cowan strain I (SAC) stimulated and unstimulated cells were cultured and IL-2, IL-10, IFN-γ, IL-12p40, IL-12p70 and IL-23 were detected in supernatants by ELISA. MeV peptides were used for MeV-specific stimulation and IFN-γ secretion of PBMC was measured by ELISPOT. Spontaneous and stimulated secretions of IL-10 were lower in SSPE compared to both control groups. T cell stimulation induced lower IFN-γ production than ICON group, but higher IL-2 than NICON group in SSPE. Stimulated PBMC produced lower IL-12p70 in SSPE and had decreased CD46 on the cell surface, suggesting the interaction with the virus. IFN-γ responses against MeV peptides were not prominent and similar to NICON patients. The immune response did not reveal an inflammatory activity to eliminate the virus in SSPE patients. Even IL-10 production was diminished implicating that the response is self-limited in controlling the disease.

Adult-Onset Subacute Sclerosing Panencephalitis With a 30-Year Latent Period

Subacute sclerosing panencephalitis (SSPE) is a rare progressive neuroinfectious disease due to a late complication of the measles virus. The hallmark clinical features of this disease include behavioral changes, myoclonus, dementia, visual disturbances, and pyramidal and extrapyramidal signs. The presence of characteristic high-amplitude periodic complexes on electroencephalography and raised antibody titers against measles in the cerebrospinal fluid help solidify the diagnosis. We present a case of a 40-year-old patient with SSPE who initially developed ophthalmologic manifestations 30 years after the primary measles infection. This case highlights both typical and atypical features of SSPE and provides a diagnostic framework for evaluating cases that fall outside of the standard scope of this disease.

IL28B, IL29 and micro-RNA 548 in subacute sclerosing panencephalitis as a rare disease

Subacute sclerosing panencephalitis (SSPE) is a progressive neurodegenerative disease which affects children and young adults, caused by a persistent infection of defective measles virus. IFN-λs (IL-28A, IL-28B and IL-29) are a group of cytokines mediating antiviral responses. It has been shown that IL-29 levels are significantly higher in infected cells with defective measles virus. IL-29 expression is thought to be regulated at post-transcriptional level and miRNA-548 family targets the 3'UTR of the IFNL1 gene. Impaired immune system has an important role as well as viral factors in SSPE. The aim of our study investigates whether IL-28B, IL-29 levels and gene polymorphisms contribute to the damaged immune response leading to the development of SSPE. Also possible association of miR-548 family with IL-29 and SSPE is explored. Frequencies of rs12979860, rs8099917, rs30461, serum levels of IL-28B, IL-29 and expression levels of miR-548b, miR-548c, miR-548i are determined at 64 SSPE patients and 68 healthy controls. Serum IL-29 levels are statistically significant higher in SSPE patients. Allele frequencies of rs8099917 are statistically significant higher in SSPE patients and resulted G allele is found to increase 2.183-fold risk of SSPE. The expression levels of miR-548b-5p, miR-548c-5p and miR-548i are found to be statistically significant higher in SSPE patients. Dramatically increased level of IL-29 seen in patient group indicates that the elevated miR-548 expression is compensatory result of the over-activated immune system response. Further studies referred to IL28, IL29 and related miRNA's will be enlightened the pathogenesis of SSPE.

Subacute Sclerosing Panencephalitis in a Child with Human Immunodeficiency Virus Co-Infection

Subacute sclerosing panencephalitis is a fatal infectious disease of childhood caused by persistence of the measles virus in the brain. The effect of human immunodeficiency virus (HIV) co-infection on subacute sclerosing panencephalitis remains elusive and rare. We report a child who developed subacute sclerosing panencephalitis following a short latency period and a rapidly progressive course with HIV co-infection.

Subacute sclerosing panencephalitis in pregnancy

We present a case of subacute sclerosing panencephalitis that developed in a previously healthy 29-year-old pregnant woman who had returned from a trip to rural India shortly before the onset of symptoms. She was admitted to hospital at 27 weeks' gestation with a history of cognitive decline and difficulty completing simple tasks. She had no clinical signs of infection. The working diagnosis was autoimmune encephalitis, although extensive investigations did not lead to a final classifying diagnosis. The patient became comatose and developed hypertension, and an emergency caesarean section was done at 31 weeks to deliver the child, who seemed healthy. The patient died about 6 weeks after the onset of symptoms. The patient was found to have had subacute sclerosing panencephalitis at autopsy. In this Grand Round, we review the clinical features and treatment of subacute sclerosing panencephalitis, and the epidemiological and public health aspects of the case.

Subacute sclerosing panencephalitis (SSPE) the story of a vanishing disease

Subacute sclerosing panencephalitis (SSPE), is a devastating "slow virus" brain disease which affects young children who had measles some 6-7 years earlier. Although, the pandemic of SSPE during 1960-1980's was almost eradicated due to mass immunization, the disease is still taking the life of young children in countries where measles immunization is incomplete and in world regions where genetic polymorphism to this particular infection is present. The present review was written for the fortunate young generation of pediatricians and pediatric neurologists who probably have not seen a case of SSPE during their career, and for those who work in counties where the disease has not been eradicated. It is also a reminder that with full coverage of measles immunization this devastating disease can be fully eradicated.

The link between small heat shock proteins and the immune system

There is now compelling evidence that members of the family of small heat shock proteins (HSP) can be secreted by a variety of different types of cells. Secretion of small HSP may at times represent altruistic delivery of supporting and stabilizing factors from one cell to another. A probably more general effect of extracellular small HSP, however, is exerted by their ability to activate macrophages and macrophage-like cells. When doing so, small HSP induce an immune-regulatory state of activation, stimulating macrophages to suppress inflammation. For this reason, small HSP deserve consideration as broadly applicable therapeutic agents for inflammatory disorders. In one particular case, however, adaptive immune responses to the small HSP itself may subvert the protective quality of the innate immune response it triggers. This situation only applies to alpha B-crystallin, and is unique for humans as well. In this special case, local concentrations of alpha B-crystallin determine the balance between protective innate responses and destructive adaptive responses, the latter of which are held responsible for the development of multiple sclerosis lesions. This article is part of a Directed Issue entitled: Small HSPs in physiology and pathology.

Measles virus infection of the CNS: human disease, animal models, and approaches to therapy

Viral infections of the central nervous system(CNS) mostly represent clinically important, often life-threatening complications of systemic viral infections. After acute measles, CNS complications may occur early (acute postinfectious measles encephalitis, APME) or after years of viral persistence (subacute sclerosing panencephalitis, SSPE). In spite of a presumably functional cell-mediated immunity and high antiviral antibody titers, an immunological control of the CNS infection is not achieved in patients suffering from SSPE. There is still no specific therapy for acute complications and persistent MV infections of the CNS. Hamsters, rats, and (genetically unmodified and modified) mice have been used as model systems to study mechanisms of MV-induced CNS infections. Functional CD4+ and CD8+ T cells together with IFN-gamma are required to overcome the infection. With the help of recombinant measles viruses and mice expressing endogenous or transgenic receptors, interesting aspects such as receptor-dependent viral spread and viral determinants of virulence have been investigated. However, many questions concerning the lack of efficient immune control in the CNS are still open. Recent research opened new perspectives using specific antivirals such as short interfering RNA (siRNA) or small molecule inhibitors. Inspite of obvious hurdles, these treatments are the most promising approaches to future therapies.

Subacute sclerosing panencephalitis: an update

Subacute sclerosing panencephalitis (SSPE) is a chronic encephalitis occurring after infection with measles virus. The prevalence of the disease varies depending on uptake of measles vaccination, with the virus disproportionally affecting regions with low vaccination rates. The physiopathology of the disease is not fully understood; however, there is evidence that it involves factors that favour humoral over cellular immune response against the virus. As a result, the virus is able to infect the neurons and to survive in a latent form for years. The clinical manifestations occur, on average, 6 years after measles virus infection. The onset of SSPE is insidious, and psychiatric manifestations are prominent. Subsequently, myoclonic seizures usually lead to a final stage of akinetic mutism. The diagnosis is clinical, supported by periodic complexes on electroencephalography, brain imaging suggestive of demyelination, and immunological evidence of measles infection. Management of the disease includes seizure control and avoidance of secondary complications associated with the progressive disability. Trials of treatment with interferon, ribavirin, and isoprinosine using different methodologies have reported beneficial results. However, the disease shows relentless progression; only 5% of individuals with SSPE undergo spontaneous remission, with the remaining 95% dying within 5 years of diagnosis.

Serum and cerebrospinal fluid cytokine concentrations in subacute sclerosing panencephalitis

Subacute sclerosing panencephalitis (SSPE) is a neurodegenerative disease due to persistent measles virus infection. Its immunopathogenesis is unknown. Tumor necrosis factor (TNF)-alpha, interleukin (IL)-2, IL-6, IL-10 and IL-4 concentrations were measured in cerebrospinal fluid (CSF) and serum samples from 30 SSPE patients and 19 control subjects by cytometric bead array. CSF and serum IFN-gamma, IL-12 and IL-18 levels were measured in 18 SSPE patients by ELISA. Serum IL-4 and IL-10 (p<0.001), CSF IL-4 (p<0.001) and IL-6 (p=0.049) concentrations were lower, and serum IL-2 concentrations, higher (p=0.001) in SSPE patients. Serum TNF-alpha and IL-6, CSF TNF-alpha, IL-10, and IL-2 concentrations were not different between SSPE and control groups. Serum IFN-gamma levels were higher in stage I and II than stage III patients (p<0.05), whereas there was no difference between stages in terms of other cytokines. The levels of Th2-type cytokines: IL-4, IL-6 and IL-10 were suppressed in our SSPE cases. This finding, along with relatively elevated IFN-gamma and IL-2 levels, may suggest more active effector T cells compared to regulatory T cells (Treg), especially induced Treg, in early disease. High serum IL-2 concentrations might indicate peripheral Th1 activation. Discrepancies between various reports in the literature should be examined in view of the ages, stage and treatments of the patients studied. The interplay of various cytokines or cellular systems which may vary over time and between patients. Studies of treatment measures favoring the preservation of the early inflammatory response may be of interest in SSPE.

Interleukin (IL)-12, IL-2, interferon-gamma gene polymorphisms in subacute sclerosing panencephalitis patients

Mutated measles virus variants have been claimed as the causing agent for subacute sclerosing panencephalitis (SSPE) developing several years after the recovery from measles infection. However, immune dysfunction may be considered related to a genetic susceptibility to this rare disease. Interleukin (IL)-2 -330 (rs2069 762) and +160 (rs2069 763), IL-12 p40 3' UTR (rs3213113), and interferon (IFN)-gamma +874 (rs2430561) polymorphisms are screened by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and PCR-sequence-specific priming (SSP) methods in 87 SSPE patients and 106 healthy controls (HCs) as candidate genes of susceptibility. The distribution of the IL12B genotypes (rs3213113) showed a trend for a significant difference (P = .053). The frequency of IL12B C allele (P = .04, OR: 1.6) and CC genotype (P = .03, OR: 3.2) were both higher in SSPE patients than in HC. The IL2 -330 genotypes revealed lower frequencies of GG genotype (P = .03, OR: 0.4) as well as G allele (P = .02, OR: 0.6) in SSPE. IL2 -330+160 TG haplotype was more frequent in patients (P = .005, OR: 1.8), whereas GG haplotype was less frequent, compared to controls (P = .02, OR: 0.6). IFNG +874 polymorphism revealed no difference. These findings implicate possible effects of genetic polymorphisms in the susceptibility to SSPE, which need to be confirmed in other populations.