Pasquale Ferrante

Productive Infection Maintains a Dynamic Steady State of Residual Viremia in Human Immunodeficiency Virus Type 1-Infected Persons Treated with Suppressive Antiretroviral Therapy for Five Years

ABSTRACT To provide insight into the dynamics and source of residual viremia in human immunodeficiency virus (HIV) patients successfully treated with antiretroviral therapy, 14 intensely monitored patients treated with indinavir and efavirenz sustaining HIV RNA at <50 copies/ml for >5 years were studied. Abacavir was added to the regimen of eight patients at year 5. After the first 9 months of therapy, HIV RNA levels had reached a plateau (“residual viremia”) that persisted for over 5 years. Levels of residual viremia differed among patients and ranged from 3.2 to 23 HIV RNA copies/ml. Baseline HIV DNA was the only significant pretreatment predictor of residual viremia in regression models including baseline HIV RNA, CD4 count, and patient age. In the four of five patients with detectable viremia who added abacavir to their regimen after 5 years, HIV RNA levels declined rapidly. The estimated half-life of infected cells was 6.7 days. Decrease in activated memory cells and a reduction in gamma interferon production to HIV Gag and p24 antigen in ELISpot assays were observed, consistent with a decrease in HIV replication. Thus, in patients treated with efavirenz plus indinavir, levels of residual viremia were established by 9 months, were predicted by baseline proviral DNA, and remained constant for 5 years. Even after years of highly suppressive therapy, HIV RNA levels declined rapidly after the addition of abacavir, suggesting that productive infection contributes to residual ongoing viremia and can be inhibited with therapy intensification.

Immune activation in Africa is environmentally-driven and is associated with upregulation of CCR5.

BackgroundHIV infection in Africa is associated with immune activation and a cytokine profile that stimulates CCR5 expression. We investigated whether this immune activation is environmentally driven; if a dominant expression of CCR5 could indeed be detected in African individuals; and if R5 HIV strains would be prevalent in this population. MethodsFreshly drawn peripheral blood mononuclear cells from HIV-uninfected African and Italian individuals living in rural Africa, from HIV-uninfected Africans and Italians living in Italy, and from HIV-infected African and Italian patients were analysed. Determinations of HIV coreceptor-specific mRNAs and immunophenotype analyses were performed in all samples. Virological analyses included virus isolation and characterization of plasma neutralizing activity. FindingsResults showed that: immune activation is detected both in Italian and African HIV-uninfected individuals living in Africa but not in African subjects living in Italy; CCR5-specific mRNA is augmented and the surface expression of CCR5 is increased in African compared with Italian residents (CXCR4-specific mRNA is comparable); R5-HIV strains are isolated prevalently from lymphocytes of African HIV-infected patients; and plasma neutralizing activity in HIV-infected African patients is mostly specific for R5 strains. ConclusionsImmune activation in African residents is environmentally driven and not genetically predetermined. This immune activation results in a skewing of the CCR5 : CXCR4 ratio which is associated with a prevalent isolation of R5 viruses. These data suggest that the selection of the predominant virus strain within the population could be influenced by an immunologically driven pattern of HIV co receptor expression.

Reactivation of JC virus and development of PML in patients with multiple sclerosis

The attention of researchers and clinicians specializing in both multiple sclerosis (MS) and JC virus (JCV), the etiologic agent of progressive multifocal leukoencephalopathy (PML), was rekindled by the development of PML in two patients with MS enrolled in a clinical trial of combination therapy with natalizumab (Tysabri) and interferon β-1A (Avonex) in recent years. PML had not been previously reported with either MS or treatment with interferon β alone. This occurrence of PML with α4β1-integrin inhibition in MS raised a number of issues in terms both of the scientific understanding of these diseases and for the future of immunomodulatory treatment for MS. In this review, we examine the current status of knowledge of the virus, its molecular biology, life cycle, and pathogenetic mechanisms, and how this relates to the basic science and clinical perspectives of MS. A better understanding of the specific steps from JCV infection to the development of PML is key to this issue. Other critical issues for further investigation include the role of α4β1-integrin inhibition by natalizumab in the re-expression of JCV from latent sites and in the inhibition of entry into the brain and peripheral sites.

JCV-DNA and BKV-DNA in the CNS tissue and CSF of AIDS patients and normal subjects, study of 41 cases and review of the literature

SUMMARY We studied the distribution and localization of the human papova-viruses JCV and BKV in the central nervous system (CNS) and cerebrospinal fluid (CSF) of HIV-positive patients with and without progressive multifocal leukoencephalopathy (PML) as compared with HIV-seronegative patients. The presence of JCV-DNA and BKV-DNA was evaluated by nested polymerase chain reaction (PCR) and in situ hybridization (ISH) on CNS autopsy tissues of AIDS patients with (group A, n = 13) and without (group B, n = 16) PML and of HIV-negative patients (group C, n = 12). PCR for JCV-DNA and BKV-DNA was also performed on CSF samples collected 7-420 days before death in all the 29 AIDS patients. Tissue PCR for JCV-DNA was positive in all the cases in group A, in 44 percent of the patients in group B, and in 33 percent of the patients in group C. ISH was positive in all the cases with PML and in three AIDS cases without PML (12 percent), but negative in all the HIV-negative cases. BKV-DNA was detected in two cases from group A and in one case from group B. CSF was PCR-positive for JCV-DNA in 8 of 13 (62 percent) AIDS patients with PML, but in none of the HIV patients without PML, irrespective of the presence of JCV-DNA in CNS tissues. No CSF sample was positive for BKV-DNA. Our data demonstrates that JCV-DNA and, rarely, BKV-DNA can be detected in the CNS of immunocompromised patients with and without PML and also in the CNS of HIV-negative subjects. However, only HIV-positive patients with clinically evident PML and JCV-DNA in the brain have PCR-detectable JCV-DNA in their CSF.

Immune activation in Hiv-infected African individuals

Objective:Immune activation induced by chronic infections, dietary limitations, and poor hygienic conditions is suggested to be present in African HIV infection and is at the basis of the hypothesis that HIV infection in Africa could be prevalently associated with immunopathogenetic mechanisms. Very limited data are nevertheless available supporting this theory, and in particular no data are reported on functional and phenotypic analyses performed on fresh peripheral blood mononuclear cells (PBMC) of African HIV-infected patients living in Africa. Design:Immunological and virological parameters were analysed in fresh PBMC of HIV-infected African and Italian patients with advanced HIV disease and comparable CD4 and CD8 counts, sex, and age. Both functional (antigen- and mitogen-stimulated cytokine production) and phenotypic (activation markers; markers preferentially expressed by T helper (Th) type 2 cells or by memory and naive cells) analyses were performed. Results were compared with those of HIV-seronegative African and Italian controls. HIV plasma viraemia was analysed by competitive polymerase chain reaction (PCR) and branched DNA techniques. Results:(1) The production of mitogen-stimulated IFN-γ and TNF-α as well as the production of env peptide-stimulated IFN-γ, TNF-α, and IL-10 are increased in African HIV infection; (2) the expression of activation and Th2-associated markers is augmented in African HIV infection as is the memory/naive ratio; (3) mitogen-stimulated IFN-γ and IL-10 production, as well as the expression of activation and Th2-associated markers and the memory/naive ratio, are augmented in African compared with Italian controls; and (4) plasma viraemia is reduced in African compared with Italian HIV-infected individuals. Conclusions:These results, which are the first to be reported on fresh material from African HIV-infected patients living in Africa, indicate that HIV disease is associated with an abnormal immune hyperactivation and may be accompanied in these patients by lower loads of virus, and show that such activation is present even in HIV-seronegative controls.

Lymphocyte subset patterns and cytokine production in Alzheimer's disease patients

To investigate the signs of inflammatory processes in Alzheimers disease (AD), we examined peripheral blood mononuclear cells (PBMC) from 51 AD patients (29 with mild and 22 with moderately severe dementia) and 51 age-matched healthy controls (HC), using flow cytometry to analyse the absolute number and the percentage of T, B and NK cells. We also studied the surface expression of CD25, CD28, CD57, CD71, CD45RA and CD45RO markers on cells CD4+ and CD8+. In 30 AD patients and 20 HC the production of IL-2, IFN-gamma, IL-10 and TNF-alpha by PBMC after stimulation with [25-35], [1-40] and [1-16] beta-amyloid (betaA) fragments was also evaluated. A significant decrease in circulating B and CD8+CD28- cells, as well as an increase in CD8+ cells expressing CD71+ and CD28+, was observed in AD patients. A significant decrease in IL-10 production was also found after stimulation of PMBC with betaA [1-40]. The decreased IL-10 production was not related to disease severity. The observed imbalance of immune peripheral cell subpopulations and decreased IL-10 production point to a reduction of suppressor cell function in AD patients.

Mucosal and Systemic Immune Activation Is Present in Human Immunodeficiency Virus—Exposed Seronegative Women

Immune parameters were analyzed in peripheral blood mononuclear cells (PBMC) and cervical mucosa biopsy specimens of human immunodeficiency virus (HIV)-seronegative women sexually exposed to HIV (exposed seronegative [ESN]), HIV-infected women, and healthy women without HIV exposure. HIV was not detected in PBMC or cervical mucosa biopsy specimens of ESN women. However, interleukin (IL)-6, IL-10, IL-12, interferon (IFN)-gamma, and tumor necrosis factor (TNF)-alpha and -beta mRNA were elevated in PBMC and cervical mucosa biopsy specimens of ESN and HIV-infected women; CCR5 and CXCR4 mRNA were augmented in cervical mucosa biopsy specimens, but not in PBMC, of ESN and HIV-infected women; HIV-specific IFN-gamma-secreting cells were detected in vaginal washes of ESN and HIV-infected women; and phenotypic alterations were present in PBMC of ESN women. These results suggest that active HIV infection is not required for T cell activation; immune alterations occur in women in whom HIV infection cannot be detected virologically or clinically.

Single-cell analysis of cytokine production shows different immune profiles in multiple sclerosis patients with active or quiescent disease

Peripheral blood mononuclear cells of multiple sclerosis (MS) patients were stimulated with myelin basic protein (MBP) together with anti-CD28 monoclonal antibody and staphylococcal enterotoxin B to optimize cytokine production by antigen-specific cells. Type 1 (IL-2, IL-12, IFNgamma) and pro-inflammatory (TNFalpha, IL-1beta, IL-6) cytokines were augmented in CD4+, CD8+, and CD14+ cells of acute MS patients and of patients undergoing disease reactivation. These cytokines were reduced in IFNbeta-treated and in stable MS patients; type 2 cytokines (IL-4, IL-10) were increased in these patients. Similar immune profiles are seen in MS patients in whom remission is naturally or pharmacologically (IFNbeta) achieved. Cytokine alterations are particularly evident in CD14+ cells, underlying their critical role in the modulation of the immune response.

Late-onset cerebellar ataxia with hypogonadism and muscle coenzyme Q10 deficiency

Two brothers had late-onset progressive ataxia, cerebellar atrophy, and hypergonadotropic hypogonadism associated with coenzyme Q10 (CoQ10) deficiency in skeletal muscle. Both patients improved on high-dose CoQ10 supplementation, stressing the importance of CoQ10 deficiency in the differential diagnosis of cerebellar ataxia, even when onset is late.

Human α Defensin in HIV-Exposed but Uninfected Individuals

Abstract:Human &agr; defensins 1, 2, and 3 are produced by CD8+ T cells of HIV-infected long-term nonprogressors and have an antiviral activity. &agr; Defensins were examined in peripheral blood mononuclear cells (PBMCs), cervical-vaginal mononuclear cells (CVMCs), and cervical biopsies of 9 HIV-1-exposed but uninfected women (ESNs), 10 HIV-infected patients (HIV), and 13 low-risk healthy controls (HCs). Results showed that, whereas &agr; defensin production and &agr; defensin-expressing CD8 lymphocytes were comparable in ESNs and HIV patients, constitutive &agr; defensin production by peripheral CD8 and CVMCs was augmented in ESNs compared with HCs (P = 0.001 and P = 0.058, respectively); &agr; defensin mRNA was increased in PBMCs of ESNs; unstimulated, &agr; defensin-expressing peripheral and mucosal CD8 lymphocytes were 10-fold higher in ESNs compared with HCs (P = 0.003 and P = 0.01, respectively); and &agr; defensin mRNA and &agr; defensin-expressing cells were augmented in cervical biopsies of ESN compared with HCs (mRNA:P = 0.03). The differences were reduced upon in vitro mitogen stimulation. A robust constitutive production of &agr; defensin is seen in HIV-exposed uninfected individuals; these peptides could have a role in the potentially protective immune response that characterizes ESNs.