Morphological and molecular comparison of HIV-associated and sporadic inclusion body myositis.

OBJECTIVE: The molecular characteristics of sporadic inclusion body myositis (sIBM) have been intensively studied, and specific patterns on the cellular, protein and RNA level have emerged. However, these characteristics have not been studied in the context of HIV-associated IBM (HIV-IBM). In this study, we compared clinical, histopathological, and transcriptomic patterns of sIBM and HIV-IBM. METHODS: In this cross-sectional study, we compared patients with HIV-IBM and sIBM based on clinical and morphological features as well as gene expression levels of specific T-cell markers in skeletal muscle biopsy samples. Non-disease individuals served as controls (NDC). Cell counts for immunohistochemistry and gene expression profiles for quantitative PCR were used as primary outcomes. RESULTS: 14 muscle biopsy samples (7 HIV-IBM, 7 sIBM) of patients and 6 biopsy samples from NDC were included. Clinically, HIV-IBM patients showed a significantly lower age of onset and a shorter period between symptom onset and muscle biopsy. Histomorphologically, HIV-IBM patients showed no KLRG1+ or CD57+ cells, while the number of PD1+ cells did not differ significantly between the two groups. All markers were shown to be significantly upregulated at gene expression level with no significant difference between the IBM subgroups. CONCLUSION: Despite HIV-IBM and sIBM sharing important clinical, histopathological, and transcriptomic signatures, the presence of KLRG1+ cells discriminated sIBM from HIV-IBM. This may be explained by longer disease duration and subsequent T-cell stimulation in sIBM. Thus, the presence of TEMRA cells is characteristic for sIBM, but not a prerequisite for the development of IBM in HIV+ patients.

Clinical improvement precedes lesion size regression in a severe case of acute disseminated encephalomyelitis.

Here, we present a case of a severe acute disseminated encephalomyelitis (ADEM) of a 42-year-old male patient. The diagnosis was established after brain biopsy and due to acutely evolving encephalopathy occurring in the context of atypical Mycoplasma pneumoniae (MP). We analysed the prominent MRI white matter lesions using a three-dimensional algorithm as cutting-edge technique to study morphological abnormalities and correlated them to the clinical condition of the patient. We found a discrepancy between the lesion size and the clinical deficits of the patient, actually the clinical improvement antedated the regression of the white matter lesions.

CD34+ progenitor cells mobilized by natalizumab are not a relevant reservoir for JC virus.

BACKGROUND: Progressive multifocal leukoencephalopathy (PML) is associated with natalizumab treatment in patients with multiple sclerosis (MS). It has been hypothesized that natalizumab mobilizes JC virus (JCV)-infected haematopoietic progenitor cells mediating viraemia and subsequently this disease. OBJECTIVE: The objective of this study was to investigate peripheral haematopoietic progenitor cells for evidence of JCV DNA in MS patients treated with natalizumab. METHODS: We assessed JCV and cytomegalovirus (CMV) DNA in magnetically separated CD34+ haematopoietic progenitor cells, peripheral blood mononuclear cells and plasma of 67 natalizumab-treated patients with MS and six PML patients. RESULTS: Viral DNA was not detectable in CD34+ haematopoietic progenitor or peripheral blood mononuclear cells from any sample. Two plasma samples from patients with MS while undergoing natalizumab treatment were JCV-positive. In one case clinically manifest PML developed 8 months thereafter. CONCLUSIONS: Our findings do not support the hypothesis that natalizumab mobilizes JC virus-infected CD34+ cells from the bone marrow mediating JC viraemia. Notably, JC viraemia was detected in one patient with MS prior to developing clinical PML. This warrants further study.

Natalizumab-associated progressive multifocal leukoencephalopathy in patients with multiple sclerosis: lessons from 28 cases.

BACKGROUND: Treatment of multiple sclerosis with natalizumab is complicated by rare occurrence of progressive multifocal leukoencephalopathy (PML). Between July, 2006, and November, 2009, there were 28 cases of confirmed PML in patients with multiple sclerosis treated with natalizumab. Assessment of these clinical cases will help to inform future therapeutic judgments and improve the outcomes for patients. RECENT DEVELOPMENTS: The risk of PML increases with duration of exposure to natalizumab over the first 3 years of treatment. No new cases occurred during the first two years of natalizumab marketing but, by the end of November, 2009, 28 cases had been confirmed, of which eight were fatal. The median treatment duration to onset of symptoms was 25 months (range 6-80 months). The presenting symptoms most commonly included changes in cognition, personality, and motor performance, but several cases had seizures as the first clinical event. Although PML has developed in patients without any previous use of disease-modifying therapies for multiple sclerosis, previous therapy with immunosuppressants might increase risk. Clinical diagnosis by use of MRI and detection of JC virus in the CSF was established in all but one case. Management of PML has routinely used plasma exchange (PLEX) or immunoabsorption to hasten clearance of natalizumab and shorten the period in which natalizumab remains active (usually several months). Exacerbation of symptoms and enlargement of lesions on MRI have occurred within a few days to a few weeks after PLEX, indicative of immune reconstitution inflammatory syndrome (IRIS). This syndrome seems to be more common and more severe in patients with natalizumab-associated PML than it is in patients with HIV-associated PML. WHERE NEXT?: Diagnosis of natalizumab-associated PML requires optimised clinical vigilance, reliable and sensitive PCR testing of the JC virus, and broadened criteria for recognition of PML lesions by use of MRI, including contrast enhancement. Optimising the management of IRIS reactions will be needed to improve outcomes. Predictive markers for patients at risk for PML must be sought. It is crucial to monitor the risk incurred during use of natalizumab beyond 3 years.

Measurement of soluble inflammatory mediators in cerebrospinal fluid of human immunodeficiency virus-positive patients at distinct stages of infection by solid-phase protein array.

The objective of this study was to evaluate immune cytokine expression in cerebrospinal fluid (CSF) of patients with human immunodeficiency virus-1 (HIV-1)-associated dementia (HAD) using a novel cytokine array assay. HIV-1 induces a condition resembling classical subcortical dementia, known as HAD. The immune mechanisms contributing to HAD have not been elucidated. Cytokine expression in CSF was determined by solid-phase protein array in 33 neurologically asymptomatic HIV-positive male patients and were compared to levels in non-HIV controls and patients with HAD. Neurological examinations and lumbar and venous punctures were conducted in all patients and controls. Interleukin (IL)-1, IL-4, and IL-10, were up-regulated in all treated acquired immunodeficiency syndrome (AIDS) patients independent of neurological status compared to controls. In contrast, interferon gamma (IFN-gamma), IL-1alpha, IL-15, and tumor necrosis factor alpha (TNF-alpha) were highly expressed in patients with HAD compared to undemented HIV-positive patients. These results show that solid-phase protein array can detect immunological changes in patients infected with HIV. Cytokine expression levels differ in different disease stages and in patients on different treatment paradigms. Pending further validation on a larger number of patients, this method may be a useful tool in CSF diagnostics and the longitudinal evaluation of patient with HAD.

Severe aseptic leucoencephalopathy as immune reconstitution inflammatory syndrome in Caucasian and African patients.

Immune reconstitution inflammatory syndrome (IRIS) after HAART may become manifest in form of aseptic severe leucoencephalopathy. All HIV-1-positive patients in this case series had widespread laboratory tests and follow-up MRI in order to investigate the course and the underlying pathophysiology of IRIS-associated leucoencephalopathy. All patients were treated with corticosteroids, in spite of additional immunosuppression. Three patients were successfully treated with corticosteroids and survived up to now, one died. A neuropathological examination was performed showing massive aseptic intraparenchymal and perivascular invasion of cytotoxic CD8 cells. It is assumed that IRIS-associated leucoencephalopathy is based on other preconditions in Africans and Caucasians.

Cidofovir in combination with HAART and survival in AIDS-associated progressive multifocal leukoencephalopathy.

Progressive multifocal leukoencephalopathy is a demyelinating disease with a high mortality caused by the JC virus and occurs in about 5% of HIV-infected patients. Highly active anti-retroviral therapy (HAART) has a proven efficacy in prolonging the survival of patients with AIDS-associated PML, but there are differing opinions about adding cidofovir to the treatment of PML. To investigate the benefit of HAART combined with cidofovir, we retrospectively analysed the survival of 33 patients with AIDS-associated PML proven by PCR in CSF, biopsy or at autopsy. Additionally, we also analysed 37 patients with probable PML. Seventeen (51.5%) of the patients with confirmed PML were treated with HAART and 14 (42.4%) with cidofovir in any combination. Of these patients, 13 (39.4%) were treated with HAART and cidofovir in combination, four (12.1%) patients received only HAART without cidofovir and one (3%) patient received only cidofovir without HAART. Fifteen patients did not receive HAART or cidofovir. The cumulative survival was significantly longer in patients with HAART than in patients without HAART (p = 0.006), independent whether cidofovir was given or not. In comparison with single therapy with HAART, the combination of HAART and cidofovir showed no significant increase in survival (p = 0.435). Therefore, a benefit for cidofovir in addition to HAART in the treatment of PML in HIV-infected patients could not be proven.

Viral load determines the B-cell response in the cerebrospinal fluid during human immunodeficiency virus infection.

OBJECTIVE: Human immunodeficiency virus (HIV) infection of the central nervous system (CNS) is frequently associated with intrathecal immunoglobulin synthesis and cerebrospinal fluid (CSF) pleocytosis, but little is known about the B-cell response in the CSF of these patients. In this study, we investigated the relation between virus load and the frequency and phenotype of B cells in the CSF of HIV-infected patients. METHODS: The distribution of T cells, B cells, short-lived plasmablasts, and long-lived plasma cells was analyzed by flow cytometry in CSF and peripheral blood of 33 patients with HIV infection compared with 12 patients with noninfectious CNS diseases. HIV RNA copy number in CSF and serum was quantified by kinetic polymerase chain reaction. RESULTS: B-cell and plasmablast levels were increased in the CSF of HIV-infected patients compared with patients with noninfectious CNS diseases. Whereas CSF B cells were found at similar frequency during early and late stages of HIV infection, plasmablasts were more prevalent in the CSF during early infection. Plasmablasts in the CSF correlated with intrathecal IgG synthesis and even stronger with HIV RNA copy numbers in CSF, in particular, in untreated, early HIV-infected individuals. Initiation of antiviral treatment in therapy-naive patients strongly decreased HIV copy numbers and plasmablasts in CSF. INTERPRETATION: Our findings demonstrate that HIV infection of the CNS triggers an early profound B-cell response, with plasmablasts serving as the main virus-related B-cell subset in the CSF.

Altered CD4+/CD8+ T-cell ratios in cerebrospinal fluid of natalizumab-treated patients with multiple sclerosis.

BACKGROUND: Treatment with natalizumab, a monoclonal antibody against the adhesion molecule very late activation antigen 4, an alpha4beta(1) integrin, was recently associated with the development of progressive multifocal leukoencephalopathy, a demyelinating disorder of the central nervous system caused by JC virus infection. OBJECTIVE: To test the effect of natalizumab treatment on the CD4(+)/CD8(+) T-cell ratios in cerebrospinal fluid (CSF) and peripheral blood. DESIGN: Prospective longitudinal study. SETTING: Academic and private multiple sclerosis centers. PATIENTS: Patients with multiple sclerosis (MS) treated with natalizumab, untreated patients with MS, patients with other neurologic diseases, and human immunodeficiency virus-infected patients. MAIN OUTCOME MEASURES: CD4(+) and CD8(+) T cells were enumerated in CSF and peripheral blood. The mean fluorescence intensity of unbound alpha4 integrin on peripheral blood CD4(+) and CD8(+) T cells was analyzed before and after natalizumab therapy. RESULTS: Natalizumab therapy decreased the CSF CD4(+)/CD8(+) ratio of patients with MS to levels similar to those of human immunodeficiency virus-infected patients. CD4(+)/CD8(+) ratios in peripheral blood in patients with MS progressively decreased with the number of natalizumab doses, but they remained within normal limits. Six months after the cessation of natalizumab therapy, CSF CD4(+)/CD8(+) ratios normalized. The expression of unbound alpha4 integrin on peripheral blood T cells decreases with natalizumab therapy and was significantly lower on CD4(+) vs CD8(+) T cells. CONCLUSIONS: Natalizumab treatment alters the CSF CD4(+)/CD8(+) ratio. Lower expression of unbound alpha4 integrin on CD4(+) T cells is one possible mechanism. These results may have implications for the observation that some natalizumab-treated patients with MS developed progressive multifocal leukoencephalopathy.

Immune surveillance in multiple sclerosis patients treated with natalizumab.

OBJECTIVE: Our objective was to test whether natalizumab, an antibody against very late activating antigen (VLA)-4, interferes with central nervous system immune surveillance as assessed by leukocyte cell numbers and cellular phenotypes in cerebrospinal fluid (CSF) and peripheral blood. METHODS: Cell numbers and cellular phenotypes in CSF and peripheral blood were analyzed in multiple sclerosis (MS) patients treated with natalizumab, untreated MS patients, and patients with other neurological disease (OND). JC virus DNA in the CSF and peripheral blood was quantified by kinetic polymerase chain reaction. RESULTS: CSF leukocyte counts, CD4(+) and CD8(+) T cells, CD19(+) B cells, and CD138(+) plasma cells were significantly lower in natalizumab-treated MS patients compared with OND patients and untreated MS patients. JC virus DNA was not detected in CSF or peripheral blood from natalizumab-treated patients. Six months after cessation of natalizumab therapy, low lymphocyte counts in the CSF persisted. The patient with the highest total leukocyte and CD4(+) and CD8(+)T-cell counts in the CSF experienced a clinical relapse. INTERPRETATION: These data suggest that natalizumab treatment results in a prolonged decrease of lymphocytes in the CSF and are consistent with the hypothesis that natalizumab impairs immune surveillance of the central nervous system.

Cerebrospinal fluid HIV viral load in different phases of HIV-associated brain disease.

We compared CSF HIV viral load in 33 asymptomatic HIV seropositive patients, 11 patients with incipient minor motor deficits (MMD), 11 patients with sustained MMD, and 16 patients with HIV-associated dementia. Patients with incipient MMD showed significantly higher CSF viral load than asymptomatic patients. Demented patients also had higher CSF viral loads than asymptomatic patients. This phenomenon is independent of antiretroviral therapy. Thus, correlation of viral load with time suggests a multiphasic course of HIV-associated CNS disease.

Association of human polyomavirus JC with peripheral blood of immunoimpaired and healthy individuals.

JC virus (JCV) infection is regularly asymptomatic in healthy individuals. In contrast, in immunocompromised individuals, highly activated virus replication may lead to PML. Peripheral blood cells (PBCs) are found to harbor JCV DNA in healthy and diseased individuals and it is discussed that they might be responsible for dissemination of the virus to the central nervous system (CNS) during persistence. To better understand the role of JCV DNA in PBCs for persistent infection and pathogenesis, the authors characterized the extent of JCV infection in Ficoll-gradient purified blood cells (peripheral blood mononuclear cells [PBMCs]) of healthy and human immunodeficiency virus type 1 (HIV-1)-infected individuals. Virus activation in PBMCs from healthy JCV-infected individuals was found at a rate of 0% to 38% at low polymerase chain reaction (PCR) sensitivity. In progressive multifocal leukoencephalopathy (PML) patients, a stronger signal was found, indicating increased virus activation. JCV DNA was regularly detected in T and B lymphocytes and in monocytes at low levels. However, granulocytes were shown to be the predominant reservoir of JCV DNA harboring high copy numbers. Although the overall distribution of viral genomes holds true for the population studied, in the individual, a markedly changed pattern of distribution can be found.