Papers by Gabriella Rozera

The new microbiologica, 2010
Despite the widespread use of molecular biology techniques, standardized methods for the measurem... more Despite the widespread use of molecular biology techniques, standardized methods for the measurement of HIV-1 proviral DNA are currently lacking and several discordant results are still present in different studies. To assess the clinical meaning of the proviral DNA load, a study group comprising seven different laboratories was set up to standardize a HIV-1 proviral DNA quantification method able to assess the DNA proviral load of the most relevant circulating HIV-1 subtypes. Reference samples (24 cellular samples infected with HIV-1 clade B, and 40 samples of peripheral blood mononuclear cells containing different concentrations of plasmids expressing different HIV-1 clades) were distributed and tested blindly. All laboratories employed hTERT gene as housekeeping gene and primers within the gag gene to quantify different HIV-1 clades. Inter-laboratory results did not differ statistically but showed only minor variations concerning HIV-1 DNA amounts and different HIV clades, with a...

Open Forum Infectious Diseases
Background The pathogenesis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infec... more Background The pathogenesis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection remains unclear. We report the detection of viral RNA from different anatomical districts and the antibody profile in the first 2 COVID-19 cases diagnosed in Italy. Methods We tested for SARS-CoV-2 RNA clinical samples, either respiratory and nonrespiratory (ie, saliva, serum, urine, vomit, rectal, ocular, cutaneous, and cervico-vaginal swabs), longitudinally collected from both patients throughout the hospitalization. Serological analysis was carried out on serial serum samples to evaluate IgM, IgA, IgG, and neutralizing antibody levels. Results SARS-CoV-2 RNA was detected since the early phase of illness, lasting over 2 weeks in both upper and lower respiratory tract samples. Virus isolate was obtained from acute respiratory samples, while no infectious virus was rescued from late respiratory samples with low viral RNA load, collected when serum antibodies had been developed. Seve...

The new microbiologica, 2017
Persistent residual viremia (RV) has been demonstrated in 70-90% of patients under successful cAR... more Persistent residual viremia (RV) has been demonstrated in 70-90% of patients under successful cART. We analyzed the RV trend during the first year following cART-induced virological suppression (VS; HIVRNA <50 copies/ml) to identify predictors of achievement and maintenance of ultra-deep RV suppression (URVS; HIV-RNA <5 copies/ml) in 60 naïve patients. These patients were aligned at the time of reaching VS and were longitudinally tested with an ultrasensitive HIV-RNA assay. The influence of demographics, primary/chronic infection, pre-therapy HIV-RNA and CD4, cART regimen and time to reach VS on RV trends was evaluated. During the first year following VS, median RV levels steadily decreased. RV dropped below 5 copies/ml at least once in each patient, but URVS was maintained in 45% of patients. RV rebounded to levels fluctuating around 5-10 copies/ml while in the remaining 55% of patients. Predictors of early achievement and maintenance of stable URVS were fast (<12 weeks) V...

PloS one, 2017
Aim was to determine the dynamics of peripheral blood mononuclear cells (PBMC)- associated total ... more Aim was to determine the dynamics of peripheral blood mononuclear cells (PBMC)- associated total HIV-1 DNA in successfully ART-treated HIV/HCV co-infected patients receiving DAA treatment and to explore possible virological hypotheses underlying the phenomenon. Longitudinal, single-centre study measuring total HIV-1 DNA before the start of DAA, at the end of treatment (EOT), and 3 months after treatment. Univariable and multivariable analyses were used to assess factors associated with HIV-1 DNA increase ≥0.5 Log copies/million PBMC. Episomal 2-LTR forms, residual HIV-1 viremia and proviral DNA quasispecies evolution were also investigated. 119 successfully ART-treated HIV/HCV co-infected patients were included. Median baseline HIV-1 DNA was 3.84 Log copies/million PBMC (95%CI 3.49-4.05), and no significant variation with respect to baseline was found at EOT and after 3 months of DAA termination. In 17% of cases an increase ≥0.5 Log copies/million PBMC was observed at EOT compared t...

Proteome Science
Background: Changes in iron metabolism frequently accompany HIV-1 infection. However, while many ... more Background: Changes in iron metabolism frequently accompany HIV-1 infection. However, while many clinical and in vitro studies report iron overload exacerbates the development of infection, many others have found no correlation. Therefore, the multi-faceted role of iron in HIV-1 infection remains enigmatic. Methods: RT-qPCR targeting the LTR region, gag, Tat and Rev were performed to measure the levels of viral RNAs in response to iron overload. Spike-in SILAC proteomics comparing i) iron-treated, ii) HIV-1-infected and iii) HIV-1-infected/ iron treated T lymphocytes was performed to define modifications in the host cell proteome. Data from quantitative proteomics were integrated with the HIV-1 Human Interaction Database for assessing any viral cofactors modulated by iron overload in infected T lymphocytes. Results: Here, we demonstrate that the iron overload down-regulates HIV-1 gene expression by decreasing the levels of viral RNAs. In addition, we found that iron overload modulates the expression of many viral cofactors. Among them, the downregulation of the REV cofactor eIF5A may correlate with the iron-induced inhibition of HIV-1 gene expression. Therefore, we demonstrated that eiF5A downregulation by shRNA resulted in a significant decrease of Nef levels, thus hampering HIV-1 replication. Conclusions: Our study indicates that HIV-1 cofactors influenced by iron metabolism represent potential targets for antiretroviral therapy and suggests eIF5A as a selective target for drug development.
The new microbiologica, 2017
HIV-1 p17 plays an important role in the virus life-cycle and disease pathogenesis. Recent studie... more HIV-1 p17 plays an important role in the virus life-cycle and disease pathogenesis. Recent studies indicated a high heterogeneity of p17. A high number of insertions in the p17 carboxy-terminal region have been more frequently detected in patients with non-Hodgkin lymphoma (NHL), suggesting a role of altered p17 in lymphomagenesis. Based on p17 heterogeneity, possible PBMC/plasma compartmentalization of p17 variants was explored by ultra-deep pyrosequencing in five NHL patients. The high variability of p17 with insertions at the carboxy-terminal region was confirmed in plasma and observed for the first time in proviral genomes. Quasispecies compartmentalization was evident in 4/5 patients. Further studies are needed to define the possible role of p17 quasispecies compartmentalization in lymphomagenesis.

PloS one, 2016
In March/April 2009, a new pandemic influenza A virus (A(H1N1)pdm09) emerged and spread rapidly v... more In March/April 2009, a new pandemic influenza A virus (A(H1N1)pdm09) emerged and spread rapidly via human-to-human transmission, giving rise to the first pandemic of the 21th century. Influenza virus may be present in the infected host as a mixture of variants, referred to as quasi-species, on which natural and immune-driven selection operates. Since hemagglutinin (HA) and non-structural 1 (NS1) proteins are relevant in respect of adaptive and innate immune responses, the present study was aimed at establishing the intra-host genetic heterogeneity of HA and NS1 genes, applying ultra-deep pyrosequencing (UDPS) to nasopharyngeal swabs (NPS) from patients with confirmed influenza A(H1N1)pdm09 infection. The intra-patient nucleotide diversity of HA was significantly higher than that of NS1 (median (IQR): 37.9 (32.8-42.3) X 10-4 vs 30.6 (27.4-33.6) X 10-4 substitutions/site, p = 0.024); no significant correlation for nucleotide diversity of NS1 and HA was observed (r = 0.319, p = 0.29). ...

Http Dx Doi Org 10 1089 Aid 2009 0083, Sep 1, 2009
Near full length genome characterization of a BF recombinant from a patient who died from multior... more Near full length genome characterization of a BF recombinant from a patient who died from multiorgan failure during HIV-1 seroconversion is reported. Massive parallel pyrosequencing was used with the shotgun approach. Intrahost genetic variability along the whole genome was calculated and coreceptor usage of viral quasispecies was predicted. A consensus sequence was established to perform subtype assignment, phylogenetic analysis, and recombination tests. The sequence clustered with two recently described BF unique recombinant forms from Brazil, consistent with the recombination pattern, yielding breakpoints located at the same positions, with the exception of the second env breakpoint. The actual prevalence of recombinant forms is probably underestimated if partial genomic regions are considered. Here the first full length BF recombinant from Italy is described, together with an evaluation of quasispecies heterogeneity. Our data provide evidence that next generation sequencing may provide a major contribution to HIV-1 molecular epidemiology and to the comprehension of intrapatient heterogeneity.

Archives of Virology, Mar 1, 2006
Vero cells transfected with either neo-or bcl-2-plasmid were infected with SARS-CoV at a high mul... more Vero cells transfected with either neo-or bcl-2-plasmid were infected with SARS-CoV at a high multiplicity of infection. Apoptosis appeared after the onset of CPE and completion of virus replication, and could be prevented by Bcl-2 expression. Apoptosis is likely mediated by the mitochondrial pathway, as demonstrated by its inhibition using Bcl-2, and by the activation of the caspase cascade, resulting in PARP cleavage. Prevention of apoptosis did not affect susceptibility to infection, kinetics and extent of viral replication and release, thus implying that apoptosis is not involved in facilitating release and/or dissemination of SARS-CoV in Vero cells. * Apoptosis is an important antivirus defence mechanism of host cells, and viruses have evolved strategies to counteract and regulate apoptosis to maximize the production of virus progeny, allowing viral spread to neighbouring cells [11]. Several cytopathic viruses are able to affect the apoptotic process either through induction or inhibition mechanisms, and it is generally believed that apoptosis, besides necrosis, can mediate the cytopathic effect (CPE) induced by some viruses [8]. In recent years, many viruses have been found to induce apoptosis during

Proceedings of the National Academy of Sciences, 2015
Although in decline after successful anti-HIV therapy, B-cell lymphomas are still elevated in HIV... more Although in decline after successful anti-HIV therapy, B-cell lymphomas are still elevated in HIV-1-seropositive (HIV+) persons, and the mechanisms are obscure. The HIV-1 matrix protein p17 persists in germinal centers long after HIV-1 drug suppression, and some p17 variants (vp17s) activate Akt signaling and promote growth of transformed B cells. Here we show that vp17s derived from four of five non-Hodgkin lymphoma (NHL) tissues from HIV+ subjects display potent B-cell growth-promoting activity. They are characterized by amino acid insertions at position 117–118 (Ala–Ala) or 125–126 (Gly–Asn or Gly–Gln–Ala–Asn–Gln–Asn) among some other mutations throughout the sequence. Identical dominant vp17s are found in both tumor and plasma. Three of seven plasma samples from an independent set of NHL cases manifested multiple Ala insertions at position 117–118, and one with the Ala–Ala profile also promoted B-cell growth and activated Akt signaling. Ultradeep pyrosequencing showed that vp17s...

The new microbiologica, 2010
Despite the widespread use of molecular biology techniques, standardized methods for the measurem... more Despite the widespread use of molecular biology techniques, standardized methods for the measurement of HIV-1 proviral DNA are currently lacking and several discordant results are still present in different studies. To assess the clinical meaning of the proviral DNA load, a study group comprising seven different laboratories was set up to standardize a HIV-1 proviral DNA quantification method able to assess the DNA proviral load of the most relevant circulating HIV-1 subtypes. Reference samples (24 cellular samples infected with HIV-1 clade B, and 40 samples of peripheral blood mononuclear cells containing different concentrations of plasmids expressing different HIV-1 clades) were distributed and tested blindly. All laboratories employed hTERT gene as housekeeping gene and primers within the gag gene to quantify different HIV-1 clades. Inter-laboratory results did not differ statistically but showed only minor variations concerning HIV-1 DNA amounts and different HIV clades, with a...

Virus Research, 2013
HCV quasispecies variability represents the background for the selection of mutations and for the... more HCV quasispecies variability represents the background for the selection of mutations and for the development of drug resistance. Natural aminoacid changes in NS3, associated with reduced protease inhibitor susceptibility, have been observed in treatment-naïve patients. Massively parallel sequencing has been used to analyze NS3 quasispecies in patients infected with HCV genotype 1, naive to anti-HCV treatment, with/without HIV-coinfection, to establish the genetic heterogeneity and the presence of amino acid substitutions at positions responsible for drug resistance. Genomes carrying substitutions represented either predominant or minority components of viral quasispecies, and were observed in 85.7% of patients. Multiple substitutions, frequently associated on the same haplotype, were observed in 46.4% of patients. High resistance combinations were not detected, neither on the same genome, nor in the whole quasispecies. Heterogeneity of HCV NS3 was lower in HIV-coinfected as compared to HCV-monoinfected patients, but factors underlying this difference remain to be established. Although the relevance of naturally occurring mutations with respect of resistance development and probability of success of direct acting antivirals is questioned, UDPS may be beneficial to help understanding viral dynamics, providing high resolution view of viral diversity.

Microbiologia Medica, 2011
Viruses represent the most abundant biological components on earth.They can be found in every env... more Viruses represent the most abundant biological components on earth.They can be found in every environment, from deep layers of oceans to animal bodies.Although several viruses have been isolated and sequenced, in each environment there are millions of different types of viruses that have not been identified yet.The advent of nextgeneration sequencing technologies with their high throughput capabilities make possible to study in a single experiment all the community of microorganisms present in a particular sample "microbioma".They made more feasible the application of the metagenomic approach, by which it is also possible to discover and identify new pathogens, that may pose a threat to public health.This paper summarizes the most recent applications of nextgeneration sequencing to discover new viral pathogens during the occurrence of infection disease outbreaks.

PLoS ONE, 2013
Objective: The false-positive rate (FPR) is a percentage-score provided by Geno2Pheno-algorithm i... more Objective: The false-positive rate (FPR) is a percentage-score provided by Geno2Pheno-algorithm indicating the likelihood that a V3-sequence is falsely predicted as CXCR4-using. We evaluated the correlation between FPR obtained by V3 population-sequencing and the burden of CXCR4-using variants detected by V3 ultra-deep sequencing (UDPS) and Enhanced-Sensitivity Trofile assay (ESTA). Methods: 54 HIV-1 B-subtype infected-patients (all maraviroc-naïve), with viremia .10,000copies/ml, were analyzed. HIVtropism was assessed by V3 population-sequencing, UDPS (considering variants with .0.5% prevalence), and ESTA. Results: By UDPS, CCR5-using variants were detected in 53/54 patients, irrespective of FPR values, and their intra-patient prevalence progressively increased by increasing the FPR obtained by V3 population-sequencing (rho = 0.75, p = 5.0e-8). Conversely, the intra-patient prevalence of CXCR4-using variants in the 54 patients analyzed progressively decreased by increasing the FPR (rho = 20.61; p = 9.3e-6). Indeed, no CXCR4-using variants were detected in 13/13 patients with FPR.60. They were present in 7/18 (38.8%) patients with FPR 20-60 (intra-patient prevalence range: 2.1%-18.4%), in 5/7 (71.4%) with FPR 10-20, in 4/6 (66.7%) with FPR 5-10, and in 10/10(100%) with FPR,5 (intra-patient prevalence range: 12.1%-98.1%). Conclusions: FPR by V3 population-sequencing can predict the burden of CXCR4-using variants. This information can be used to optimize the management of tropism determination in clinical practice. Due to its low cost and short turnaround time, V3 population-sequencing may represent the most feasible test for HIV-1 tropism determination. More sensitive methodologies (as UDPS) might be useful when V3 population-sequencing provides a FPR .20 (particularly in the range 20-60), allowing a more careful identification of patients harboring CXCR4-using variants.
Journal of Virological Methods, 2010
The use of HIV-1 DNA quantitation in cellular reservoirs to predict disease progression and treat... more The use of HIV-1 DNA quantitation in cellular reservoirs to predict disease progression and treatment outcome in infected patients is hampered by the lack of standardization among the available methods. In the present study, real-time PCR methods used commonly for HIV-1 proviral DNA evaluation were compared, showing strong differences in the results, probably as a consequence of genome variability in the target regions. Standardization of HIV-1 proviral DNA quantitation assays is needed for use in clinical management of patients with HIV-1.

Journal of Medical Virology, 2007
This study aimed to define clinical and virological parameters associated with spontaneous contro... more This study aimed to define clinical and virological parameters associated with spontaneous control of HIV replication in patients having initiated HAART during primary HIV infection, who underwent structured therapy interruption by two protocols with either fixed or HIV viremia-guided scheme. At the end of the protocol all patients were changed to viremia-guided scheme and observed for 12 months (follow-up). Patients maintaining HIV viremia below the indications for resumption of HAART during the follow-up, were defined controllers, those who had to resume HAART were defined non-controllers. The following parameters were examined: pre-interruption therapy duration, CD4(+), HIV RNA, proviral DNA, evolution of viral quasispecies. No specific advantage was conferred by either interruption of structured therapy in the proportion of controllers and non-controllers. Pre-HAART and zenith CD4(+), pre-therapy interruption, HAART duration, but not pre-HAART HIV RNA, were significantly higher in controllers as compared to non-controllers. HIV RNA levels after the first interruption cycle of therapy were significantly lower in controllers than in non-controllers. Proviral DNA levels were also lower in controllers at this time point. HIV RNA and proviral DNA levels associated with the last interruption of therapy cycle were not different from those associated with the first cycle, and, in spite of multiple waves of virus rebound, very few gag quasispecies variants emerged in each patient. The data suggest that pre-treatment clinical parameters and virological events associated with the first viral rebound are crucial factors in determining the ability to control viral replication after multiple cycles of interruption of treatment.

Journal of Interferon & Cytokine Research, 2008
In the pre-highly active antiretroviral therapy (HAART) era, clinical trials showed that interfer... more In the pre-highly active antiretroviral therapy (HAART) era, clinical trials showed that interferon (IFN) treatment was able to delay AIDS progression and prolong survival. Along with HAART, ancillary use of IFN during primary infection and before HAART therapy initiation has been effective. Also endogenous IFN may positively affect the progression of HIV infection, as suggested in GB virus type C (GBV-C) coinfected patients. In this pilot study, we tried to prevent rebound of HIV replication in patients who interrupted HAART by covering the drug-free time with administration of pegylated IFN (PEGIFN). Twenty-four HIV-hepatitis C virus (HCV) patients who started IFN treatment for liver disease, after variable time from having interrupted HAART, were enrolled. HIV RNA was determined during a 2-month period. In patients who interrupted HAART at variable times before initiating IFN and, therefore, had experienced a complete viral rebound, IFN caused a significant reduction of viral load lasting at least 4 weeks. Moreover, 3 of the 4 patients who started IFN concomitantly with the HAART discontinuation showed complete control of viral rebound, delaying the resumption of viral replication for more than 2 weeks. These preliminary findings suggest that a structured therapy interruptions (STI) strategy may be feasible provided that IFN is administered during the drug-free times, possibly delaying drug resistance, lessening toxicity, reducing costs, and prolonging survival.
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Papers by Gabriella Rozera