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1.
AIDS ; 38(3): 299-308, 2024 Mar 01.
Article in English | MEDLINE | ID: mdl-37905996

ABSTRACT

OBJECTIVES: HIV-associated dementia (HAD) is the most severe clinical expression of HIV-mediated neuropathology, and the processes underlying its development remain poorly understood. We aimed to exploit high-dimensional metabolic profiling to gain insights into the pathological mechanisms associated to HAD. DESIGN: In this cross-sectional study, we utilized metabolomics to profile matched cerebrospinal fluid (CSF) and plasma samples of HAD individuals ( n  = 20) compared with neurologically asymptomatic people with HIV (ASYM, n  = 20) and healthy controls (NEG, n  = 20). METHODS: Identification of plasma and CSF metabolites was performed by liquid-chromatography or gas-chromatography following a validated experimental pipeline. The resulting metabolic profiles were analyzed by machine-learning algorithms, and altered pathways were identified by comparison with KEGG pathway database. RESULTS: In CSF, HAD patients displayed an imbalance in glutamine/glutamate ratio, decreased levels of isocitrate and arginine, and increased oxidative stress when compared with ASYM or NEG. These changes were confirmed in matched plasma samples, which in addition revealed an accumulation of eicosanoids and unsaturated fatty acids in HAD individuals. Pathway analysis in both biological fluids suggested that alterations in several metabolic processes, including protein biosynthesis, glutamate and arginine metabolism, and energy metabolism, in association to a perturbed eicosanoid metabolism in plasma, may represent the metabolic signature associated to HAD. CONCLUSION: These findings show that HAD may be associated with metabolic modifications in CSF and plasma. These preliminary data may be useful to identify novel metabolic biomarkers and therapeutic targets in HIV-associated neurological impairment.


Subject(s)
AIDS Dementia Complex , HIV Infections , Humans , Arginine/metabolism , Glutamic Acid/metabolism , Glutamic Acid/therapeutic use , Cross-Sectional Studies , HIV Infections/complications , HIV Infections/drug therapy , Metabolome , Metabolomics/methods , Energy Metabolism , Biomarkers
2.
Sensors (Basel) ; 23(23)2023 Nov 28.
Article in English | MEDLINE | ID: mdl-38067833

ABSTRACT

Digital devices have gained popularity in the last 10 years as a tool for exercise prescription, the monitoring of daily physical activity, and nutrition for the management of a health-related parameter. Therefore, the aim of this study was to assess the effectiveness of the use of digital devices to monitor exercise data in sedentary persons with HIV who exercise following an individualized activity pacing (AP) protocol on cardiorespiratory fitness body composition, blood lipid profile, and psychological parameters. Twenty-four PLWH were enrolled in an 18-week randomized, open-label, pilot AP exercise protocol. All participants were monitored by a Health Band connected to a mobile app that transmitted the data to a server. At week 3, they were randomized either in an experimental group (EG), in which an open device configuration enabled them to receive training data feedback (n = 12), or continued with no data feedback (control group, n = 12). The primary endpoint was improvement from the baseline of 15% of steady-state oxygen consumption (V˙O2) during a 6-min walking test. Technical issues occurred when pairing the health band with the app, which prevented EG participants from regularly receiving data feedback, and with data transmission to the server, which enabled only 40% monitoring of the total training days. Consequently, the study outcomes could not be compared between the two groups, and participants also lost confidence in the study. However, 19 out of 24 participants completed the AP program. Overall, only 6 (32%) improved steady-state V˙O2, with no significant changes at W18 from the baseline. Significant reductions were observed of BMI (p = 0.040), hip circumference (p = 0.027), and total-(p = 0.049) and HDL-cholesterol (p = 0.045). The failure of digital device performance substantially affected study procedures, monitoring, and participants' engagement, and likely limited the potential benefits of the AP exercise program.


Subject(s)
Cardiorespiratory Fitness , HIV Infections , Humans , Exercise/psychology , Exercise Therapy/methods , Pilot Projects
4.
Curr HIV/AIDS Rep ; 17(5): 522-528, 2020 10.
Article in English | MEDLINE | ID: mdl-32875516

ABSTRACT

PURPOSE OF REVIEW: Symptomatic cerebrospinal fluid (CSF) HIV escape defines the presence of neurological disease in combination antiretroviral therapy (cART)-treated persons due to HIV replication in CSF despite systemic suppression or to higher viral replication in CSF than in plasma. The aim was to search for cases of recurrent symptomatic CSF escape and to define their characteristics. RECENT FINDINGS: By review of the literature, we identified symptomatic CSF escape relapses in three patients who had shown clinical remission of a first escape episode following cART optimization. By examination of our cohort of 21 patients with symptomatic CSF escape, we identified five additional patients. In the latter, viral escape relapsed over a median follow-up of 108 months because of low adherence or upon treatment simplification of a previously optimized regimen. cART reoptimization based on resistance profile and potential drug neuropenetration and efficacy led to relapse resolution with no further episodes after a median follow-up of 50 months from relapse. The observation that CSF escape may relapse highlights the importance of long-term neuro-suppressive regimens after a first episode and supports the role of the brain as a reservoir for HIV.


Subject(s)
Anti-HIV Agents/therapeutic use , Cerebrospinal Fluid/virology , HIV Infections/cerebrospinal fluid , HIV Infections/drug therapy , HIV-1/drug effects , HIV-1/immunology , Adult , Chronic Disease , Female , HIV Infections/pathology , Humans , Immune Evasion/drug effects , Immune Evasion/immunology , Male , RNA, Viral/blood , Recurrence , Viral Load/drug effects , Virus Replication
5.
Article in English | MEDLINE | ID: mdl-32079244

ABSTRACT

Sarcopenia is a physiopathological process associated with aging, caused by reduction of muscle strength, muscle quality and physical performance, and associated with an increased risk of falls, physical disability and premature death. There is no effective treatment for sarcopenia, but physical exercise seems to be highly effective at counteracting the decline in muscle mass and strength associated with aging. Recently, sarcopenia has been recognized as an emerging issue in people living with HIV (PLWH). Despite adequate treatment with combination antiretroviral therapy (cART), PLWH may exhibit an early occurrence of some aging-related conditions, including sarcopenia, frailty and falls, and this is likely resulting from high rates of comorbidities, high-risk behaviours, chronic immune activation and cART-specific factors. In this review, we discuss the potential mechanisms and the clinical relevance of sarcopenia in PLWH, and present data from longitudinal studies of physical activity in this population. Despite none of these studies having specifically addressed the benefits of physical exercise on sarcopenia, there is evidence that exercise is effective to increase aerobic capacity and muscle strength, and to improve body composition and inflammatory outcomes in PLWH. Therefore, the expected benefits of physical exercise are likely to translate into a successful and specific intervention for prevention and treatment of sarcopenia in this population.


Subject(s)
Exercise , HIV Infections/complications , Muscle Strength/physiology , Muscle Weakness/rehabilitation , Sarcopenia/rehabilitation , Aging/physiology , Anti-HIV Agents/therapeutic use , Female , HIV Infections/drug therapy , Humans , Male , Muscle Weakness/physiopathology , Muscle, Skeletal , Sarcopenia/diagnosis
6.
Med Sci Sports Exerc ; 52(2): 425-433, 2020 02.
Article in English | MEDLINE | ID: mdl-31415448

ABSTRACT

PURPOSE: This study aimed to assess 16-wk improvements of physical fitness, metabolic, and psychological parameters in people living with HIV (PLWH) exercising with the support of a smartphone application, as compared with a control group exercising without application. METHODS: This was a randomized, open-label, pilot study enrolling PLWH in a 16-wk protocol consisting of moderate physical activity three times per week, which included an initial coach-supervised period of 4 wk, followed by 12 wk where participants trained independently. Participants were allocated to either an experimental group that trained using a smartphone application (APP) or a control group that practiced following a hard copy training program (No-APP). At baseline (BL) and after 16 wk (W16), patients were assessed for cardiorespiratory fitness, body composition, blood lipid profile, and POMS. RESULTS: Forty-eight PLWH were screened and 38 were eligible: 20 were allocated to the APP group and 18 to the No-APP group. Two APP and two No-APP participants were lost to follow-up. Intention-to-treat analysis showed a W16 improvement from BL of ≥15% V˙ O2peak in 13 (72%) of 18 in APP, but only in 3 (19%) of 16 in No-APP participants (P = 0.025). Significant W16 improvements were observed in APP, but not in No-APP participants, in V˙O2peak; fat mass and fat-free mass percent; total cholesterol, LDL cholesterol, and triglycerides; vigor; and total mood by POMS. Accordingly, significant percent change differences between the APP and the No-APP groups were observed in V˙O2peak; fat and fat-free mass percent; total cholesterol, LDL cholesterol, and triglycerides; and depression, vigor, anger, and total mood by POMS. CONCLUSIONS: Exercising using a smartphone application improved cardiorespiratory fitness, body composition, cholesterol profiles, and psychological outcomes in PLWH.


Subject(s)
Affect , Body Composition/physiology , Cardiorespiratory Fitness/physiology , Exercise Therapy/methods , HIV Infections/physiopathology , HIV Infections/psychology , Mobile Applications , Adult , Anti-HIV Agents/therapeutic use , Female , HIV Infections/drug therapy , Humans , Lipids/blood , Male , Middle Aged , Patient Compliance , Pilot Projects , Smartphone
7.
AIDS ; 33 Suppl 2: S159-S169, 2019 12 01.
Article in English | MEDLINE | ID: mdl-31789816

ABSTRACT

: Cerebrospinal fluid (CSF) viral escape is defined by detectable HIV-RNA in CSF despite undetectable or lower-than-CSF level in plasma of patients receiving combination antiretroviral therapy (cART). This condition may occasionally be associated with neurological problems, consisting of new and progressive cognitive decline and/or focal symptoms and signs, defining the 'symptomatic CSF escape'. Brain MRI usually shows diffuse white matter hyperintensities that recall the presentation of HIV encephalopathy in the precART era. However, patients develop symptomatic CSF escape with relatively high CD4 cell counts and suppressed or low systemic virus replication. In addition, the frequent CSF pleocytosis and the pathological demonstration of CD8 T-cell brain infiltrates in some cases of symptomatic escape indicate that inflammation is an important component in the pathogenesis of this condition. Low nadir CD4 cells are common, likely reflecting the establishment of a HIV reservoir in the central nervous system (CNS). CSF escape seems to result from reactivation of CNS infection when cART potency is lowered, because of low patient's adherence, drug resistance, or use of drug combinations that are poorly effective in the CNS and cART optimization is key to revert escape and neurological disease in the great majority of cases.


Subject(s)
Anti-Retroviral Agents/therapeutic use , HIV Infections/cerebrospinal fluid , HIV Infections/drug therapy , HIV/isolation & purification , AIDS Dementia Complex/drug therapy , Blood-Brain Barrier , CD4 Lymphocyte Count , CD4-Positive T-Lymphocytes/virology , CD8-Positive T-Lymphocytes/virology , HIV/physiology , Humans , Plasma/virology , Virus Replication
8.
Virus Res ; 269: 197631, 2019 08.
Article in English | MEDLINE | ID: mdl-31136823

ABSTRACT

The human immunodeficiency virus type-1 (HIV-1) establishes a state of latent infection in a small number of CD4+ T lymphocytes that, nonetheless, represent a major obstacle to viral eradication. We here show that Tripartite Motif-containing protein 22 (TRIM22), an epigenetic inhibitor of Specificity protein 1 (Sp1)-dependent HIV-1 transcription, is a relevant factor in maintaining a state of repressed HIV-1 expression at least in CD4+ T cell lines. By knocking-down (KD) TRIM22 expression, we observed an accelerated reactivation of a doxycycline (Dox)-controlled HIV-1 replication in the T lymphocytic SupT1 cell line. Furthermore, we here report for the first time that TRIM22 is a crucial factor for maintaining a state of HIV-1 quiescence in chronically infected ACH2 -T cell line while its KD potentiated HIV-1 expression in both ACH-2 and J-Lat 10.6 cell lines upon cell stimulation with either tumor necrosis factor-α (TNF-α) or histone deacetylase inhibitors (HDACi). In conclusion, TRIM22 is a novel determinant of HIV-1 latency, at least in T cell lines, thus representing a potential pharmacological target for strategies aiming at curtailing or silencing the pool of latently infected CD4+ T lymphocytes constituting the HIV-1 reservoir in individuals receiving combination antiretroviral therapy.


Subject(s)
CD4-Positive T-Lymphocytes/virology , HIV-1/physiology , Minor Histocompatibility Antigens/immunology , Repressor Proteins/immunology , Tripartite Motif Proteins/immunology , Virus Latency , CD4-Positive T-Lymphocytes/drug effects , Cell Line , Gene Knockdown Techniques , Histone Deacetylase Inhibitors/pharmacology , Humans , Minor Histocompatibility Antigens/genetics , Proviruses/physiology , Repressor Proteins/genetics , Tripartite Motif Proteins/genetics , Tumor Necrosis Factor-alpha/pharmacology , Virus Activation
9.
Sci Rep ; 8(1): 14249, 2018 09 24.
Article in English | MEDLINE | ID: mdl-30250078

ABSTRACT

We have reported that short-term stimulation of primary human monocyte-derived macrophages (MDM) with interferon-γ (IFN-γ) and tumor necrosis factor-α (TNF-α), i.e. M1 polarization, leads to a significant containment of virus replication. Here we show that M1-MDM restimulation with these cytokines 7 days after infection (M12 MDM) promoted an increased restriction of HIV-1 replication characterized by very low levels of virus production near to undetectable levels. In comparison to control and M1-MDM that were not restimulated, M12 MDM showed a stronger reduction of both total and integrated HIV DNA as well as of viral mRNA expression. M12 MDM were characterized by an upregulated expression of restriction factors acting at the level of reverse transcription (RT), including apolipoprotein B mRNA editing enzyme, catalytic polypeptide-like 3A (APOBEC3A) and APOBEC3G, but not SAM domain and HD domain-containing protein 1 (SAMHD1). M12 MDM also showed an increased expression of Class II Transactivator (CIITA) and Tripartite Motif22 (TRIM22), two negative regulators of proviral transcription, whereas expression and phosphorylation of transcriptional inducers of HIV-1, such as nuclear factor kB (NF-kB) and signal transducer and activator of transcription 1 (STAT1), were not impaired in these cells. The almost quiescent state of the infection in M12 MDM was promptly reversed by coculture with mitogen-stimulated leukocytes or cell incubation with their filtered culture supernatant. M12 MDM harbored replication-competent HIV-1 as virus spreading following cell stimulation was fully prevented by the RT inhibitor lamivudine/3TC. Selective reactivation of proviral expression in M12 MDM, but not in control or in M1-MDM that were not restimulated, was confirmed in cells infected with single round Vesicular Stomatitis Virus-G-pseudotyped HIV-1. Thus, M12 MDM represent an in vitro model of reversible, almost quiescent HIV-1 infection of primary human macrophages that could be further exploited for "Cure" related investigations.


Subject(s)
Cell Polarity/genetics , HIV Infections/genetics , HIV-1/genetics , Macrophages/virology , APOBEC-3G Deaminase/genetics , Apolipoproteins B/genetics , Cytidine Deaminase/genetics , DNA, Viral/genetics , Gene Expression Regulation/genetics , HIV Infections/pathology , HIV Infections/virology , HIV-1/pathogenicity , Humans , Interferon-gamma/genetics , Macrophages/metabolism , Macrophages/pathology , Minor Histocompatibility Antigens/genetics , Nuclear Proteins/genetics , Primary Cell Culture , Proteins/genetics , Repressor Proteins/genetics , SAM Domain and HD Domain-Containing Protein 1/genetics , Trans-Activators/genetics , Tripartite Motif Proteins/genetics , Tumor Necrosis Factor-alpha/genetics , Virus Latency/genetics , Virus Replication/genetics
10.
Front Immunol ; 8: 564, 2017.
Article in English | MEDLINE | ID: mdl-28555140

ABSTRACT

Among interferon (IFN) inducible antiviral factors both tripartite motif-containing protein 22 (TRIM22) and class II transactivator (CIITA) share the capacity of repressing human immunodeficiency virus type 1 (HIV-1) proviral transcription. TRIM22 is constitutively expressed in a subset of U937 cell clones poorly permissive to HIV-1 replication, whereas CIITA has been shown to inhibit virus multiplication in both T lymphocytic and myeloid cells, including poorly HIV-1 permissive U937 cells, by suppressing Tat-mediated transactivation of HIV-1 transcription. Therefore, we tested whether TRIM22 and CIITA could form a nuclear complex potentially endowed with HIV-1 repressive functions. Indeed, we observed that TRIM22, independent of its E3 ubiquitin ligase domain, interacts with CIITA and promotes its recruitment into nuclear bodies. Importantly, TRIM19/promyelocytic leukemia (PML) protein, another repressor of HIV-1 transcription also acting before proviral integration, colocalize in these nuclear bodies upon TRIM22 expression induced by IFN-γ. Finally, tTRIM22 nuclear bodies also contained CyclinT1, a crucial elongation factor of HIV-1 primary transcripts. These findings show that TRIM22 nuclear bodies are a site of recruitment of factors crucial for the regulation of HIV-1 transcription and highlight the potential existence of a concerted action between TRIM22, CIITA, and TRIM19/PML to maintain a state of proviral latency, at least in myeloid cells.

11.
Sci Rep ; 7: 44286, 2017 03 10.
Article in English | MEDLINE | ID: mdl-28281680

ABSTRACT

Zika virus (ZIKV) is a recently re-emerged flavivirus transmitted to humans by mosquito bites but also from mother to fetus and by sexual intercourse. We here show that primary human endometrial stromal cells (HESC) are highly permissive to ZIKV infection and support its in vitro replication. ZIKV envelope expression was detected in the endoplasmic reticulum whereas double-stranded viral RNA colocalized with vimentin filaments to the perinuclear region. ZIKV productive infection also occurred in the human T-HESC cell line together with the induction of interferon-ß (IFN-ß) and of IFN-stimulated genes. Notably, in vitro decidualization of T-HESC with cyclic AMP and progesterone upregulated the cell surface expression of the ZIKV entry co-receptor AXL and boosted ZIKV replication by ca. 100-fold. Thus, endometrial stromal cells, particularly if decidualized, likely represent a crucial cell target of ZIKV reaching them, either via the uterine vasculature in the viremic phase of the infection or by sexual viral transmission, and a potential source of virus spreading to placental trophoblasts during pregnancy.


Subject(s)
Endometrium/virology , Stromal Cells/virology , Virus Replication/physiology , Zika Virus/physiology , Adult , Animals , Cell Line , Cells, Cultured , Chlorocebus aethiops , Endometrium/cytology , Female , Gene Expression , Host-Pathogen Interactions/genetics , Humans , Interferon-beta/genetics , Interferon-beta/metabolism , Vero Cells , Viral Envelope Proteins/genetics , Viral Envelope Proteins/metabolism , Virus Replication/genetics , Zika Virus/genetics , Zika Virus Infection/genetics , Zika Virus Infection/metabolism , Zika Virus Infection/virology
13.
J Transl Med ; 14: 94, 2016 Apr 18.
Article in English | MEDLINE | ID: mdl-27089879

ABSTRACT

BACKGROUND: We previously demonstrated that the HLA class II transactivator CIITA inhibits HIV-1 replication in T cells by competing with the viral transactivator Tat for the binding to Cyclin T1 subunit of the P-TEFb complex. Here, we analyzed the anti-viral function of CIITA in myeloid cells, another relevant HIV-1 target cell type. We sinvestigated clones of the U937 promonocytic cell line, either permissive (Plus) or non-permissive (Minus) to HIV-1 replication. This different phenotype has been associated with the expression of TRIM22 in U937 Minus but not in Plus cells. METHODS: U937 Plus cells stably expressing CIITA were generated and HLA-II positive clones were selected by cell sorting and cloning. HLA and CIITA proteins were analyzed by cytofluorometry and western blotting, respectively. HLA-II DR and CIITA mRNAs were quantified by qRT-PCR. Tat-dependent transactivation was assessed by performing the HIV-1 LTR luciferase gene reporter assay. Cells were infected with HIV-1 and viral replication was evaluated by measuring the RT activity in culture supernatants. RESULTS: CIITA was expressed only in HLA-II-positive U937 Minus cells, and this was strictly correlated with inhibition of Tat-dependent HIV-1 LTR transactivation in Minus but not in Plus cells. Overexpression of CIITA in Plus cells restored the suppression of Tat transactivation, confirming the inhibitory role of CIITA. Importantly, HIV-1 replication was significantly reduced in Plus-CIITA cells with respect to Plus parental cells. This effect was independent of TRIM22 as CIITA did not induce TRIM22 expression in Plus-CIITA cells. CONCLUSIONS: U937 Plus and Minus cells represent an interesting model to study the role of CIITA in HIV-1 restriction in the monocytic/macrophage cell lineage. The differential expression of CIITA in CIITA-negative Plus and CIITA-positive Minus cells correlated with their capacity to support or not HIV-1 replication, respectively. In Minus cells CIITA targeted the viral transactivator Tat to inhibit HIV-1 replication. The generation of Plus-CIITA cells was instrumental to demonstrate the specific contribution of CIITA in terms of inhibition of Tat activity and HIV-1 restriction, independently from other cellular factors, including TRIM22. Thus, CIITA acts as a general restriction factor against HIV-1 not only in T cells but also in myeloid cells.


Subject(s)
HIV-1/physiology , Myeloid Cells/metabolism , Myeloid Cells/virology , Nuclear Proteins/metabolism , Trans-Activators/metabolism , Virus Replication/physiology , tat Gene Products, Human Immunodeficiency Virus/metabolism , Clone Cells , HEK293 Cells , Humans , Phenotype , Terminal Repeat Sequences/genetics , Transcriptional Activation
14.
Retrovirology ; 12: 104, 2015 Dec 18.
Article in English | MEDLINE | ID: mdl-26683615

ABSTRACT

BACKGROUND: Intracellular defense proteins, also referred to as restriction factors, are capable of interfering with different steps of the viral life cycle. Among these, we have shown that Tripartite motif 22 (TRIM22) suppresses basal as well as phorbol ester-induced HIV-1 long terminal repeat (LTR)-mediated transcription, independently of its E3 ubiquitin ligase activity, nuclear factor kappa-light-chain-enhancer of activated B cells (NF-kB) binding to the U3 region and Tat interaction with the TAR region of the HIV-1 LTR. As basal HIV-1 transcription is driven by the transcription factor specificity protein 1 (Sp1), we have investigated whether TRIM22 could interfere with Sp1-driven transcriptional activation of the HIV-1 LTR. FINDINGS: 293T cells, devoid of endogenous TRIM22 expression, were transfected with a TRIM22-expressing plasmid together with reporter plasmids driven by the HIV-1 LTR promoter either containing or lacking Sp1 binding sites or with reporter plasmids driven by non-viral promoter sequences either containing or lacking the three Sp1 binding sites from the HIV-1 LTR. These reporter assays showed that TRIM22 efficiently inhibited Sp1-driven transcription. Knocking down TRIM22 expression in the CD4(+) SupT1 T cell line increased the replication of Sp1-dependent HIV-1 variants. TRIM22 did not interact with Sp1, but prevented binding of Sp1 to the HIV-1 promoter, as demonstrated in protein-DNA pull down and chromatin immunoprecipitation assays. CONCLUSION: TRIM22 acts as a suppressor of basal HIV-1 LTR-driven transcription by preventing Sp1 binding to the HIV-1 promoter.


Subject(s)
HIV-1/genetics , Promoter Regions, Genetic , Repressor Proteins/genetics , Repressor Proteins/metabolism , Sp1 Transcription Factor/metabolism , Transcription, Genetic , Binding Sites , CD4-Positive T-Lymphocytes/virology , DNA-Binding Proteins/metabolism , Gene Expression Regulation, Viral , Genes, Reporter , HEK293 Cells , HIV Long Terminal Repeat , HIV-1/physiology , Humans , Minor Histocompatibility Antigens , Repressor Proteins/deficiency , Sequence Deletion , Sp1 Transcription Factor/genetics , Tripartite Motif Proteins , Virus Latency , Virus Replication/genetics
15.
Nature ; 516(7531): 418-22, 2014 Dec 18.
Article in English | MEDLINE | ID: mdl-25296253

ABSTRACT

The neutralizing antibody response to influenza virus is dominated by antibodies that bind to the globular head of haemagglutinin, which undergoes a continuous antigenic drift, necessitating the re-formulation of influenza vaccines on an annual basis. Recently, several laboratories have described a new class of rare influenza-neutralizing antibodies that target a conserved site in the haemagglutinin stem. Most of these antibodies use the heavy-chain variable region VH1-69 gene, and structural data demonstrate that they bind to the haemagglutinin stem through conserved heavy-chain complementarity determining region (HCDR) residues. However, the VH1-69 antibodies are highly mutated and are produced by some but not all individuals, suggesting that several somatic mutations may be required for their development. To address this, here we characterize 197 anti-stem antibodies from a single donor, reconstruct the developmental pathways of several VH1-69 clones and identify two key elements that are required for the initial development of most VH1-69 antibodies: a polymorphic germline-encoded phenylalanine at position 54 and a conserved tyrosine at position 98 in HCDR3. Strikingly, in most cases a single proline to alanine mutation at position 52a in HCDR2 is sufficient to confer high affinity binding to the selecting H1 antigen, consistent with rapid affinity maturation. Surprisingly, additional favourable mutations continue to accumulate, increasing the breadth of reactivity and making both the initial mutations and phenylalanine at position 54 functionally redundant. These results define VH1-69 allele polymorphism, rearrangement of the VDJ gene segments and single somatic mutations as the three requirements for generating broadly neutralizing VH1-69 antibodies and reveal an unexpected redundancy in the affinity maturation process.


Subject(s)
Antibodies, Neutralizing/genetics , Complementarity Determining Regions/genetics , Influenza, Human/immunology , Mutation/genetics , Orthomyxoviridae/immunology , Adult , Amino Acid Sequence , Cells, Cultured , Complementarity Determining Regions/chemistry , Female , Hemagglutinin Glycoproteins, Influenza Virus/immunology , Humans , Immunoglobulin Heavy Chains/genetics , Influenza, Human/virology , Male , Middle Aged , Models, Molecular , Orthomyxoviridae/metabolism , Polymorphism, Genetic , Protein Binding/genetics , Protein Structure, Tertiary , Young Adult
16.
DNA Cell Biol ; 33(4): 191-7, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24611907

ABSTRACT

The human tripartite motif (TRIM) family, composed of more than 77 members, encompasses an emerging group of innate antiviral factors. Most TRIM proteins are characterized by being E3 ubiquitin ligases, but also engage in specific interactions with a variety of cellular and viral partners. They are involved in many cellular processes, including cell differentiation, transcriptional regulation, cytoskeleton remodeling, intracellular trafficking, membrane repair, and oncogenesis. In regard to antiviral immunity, they restrict both retroviruses and lentiviruses as well as other DNA and RNA viruses. This review will focus on the TRIM members endowed with anti-retroviral and anti-lentiviral activities and, in particular, human immunodeficiency virus.


Subject(s)
Antiviral Agents/immunology , HIV-1/immunology , Immunity, Innate/immunology , Lentivirus/immunology , Models, Immunological , Multiprotein Complexes/immunology , Ubiquitin-Protein Ligases/genetics , Humans , Multiprotein Complexes/genetics , Ubiquitin-Protein Ligases/immunology
17.
AIDS ; 27(15): 2335-44, 2013 Sep 24.
Article in English | MEDLINE | ID: mdl-23921607

ABSTRACT

OBJECTIVE(S): Tripartite motif-containing 22 (TRIM22) is an interferon-induced protein that inhibits HIV-1 transcription and replication in vitro. Two single nucleotide missense polymorphisms rs7935564A/G (SNP-1) and rs1063303C/G (SNP-2) characterize the coding sequence of human TRIM22 gene. We tested whether these variants affected the inhibitory effect of TRIM22 on HIV-1 replication and transcription and their potential association with HIV-1 disease. DESIGN: The allelic discrimination was determined in 182 HIV-1-negative and among HIV-1-positive individuals with advanced disease progression (advanced progressors; n = 57), normal progressors (n = 76), and long-term nonprogressors (LTNPs; n = 95). METHODS: Renilla luciferase activity was measured after infection of activated peripheral blood mononuclear cells (PBMCs) from an additional group of 61 blood donors with a recombinant HIV-1. HIV-1-long terminal repeat (LTR)-driven luciferase activity was tested in the presence of plasmid expressing TRIM22 variants in 293T cells. The SNP genotyping was determined by TaqMan assay. RESULTS: HIV-1 replication was more efficient in PBMCs from donors with SNP-1G and SNP-2G than from those with SNP-1A and SNP-2C alleles. Consistently, TRIM22-GG enhanced, whereas TRIM22-AC restricted basal HIV-1 LTR-driven transcription. In vivo, SNP-1G homozygotes and A/G heterozygotes were more frequent in advanced progressors than in LTNPs [odds ratio (OR) = 2.072, P = 0.005] or in normal progressors (OR = 1.809, P = 0.022); in contrast, SNP-2 was not associated with any state of HIV-1 disease progression. Although SNP-2 distribution was similar among the groups, TRIM22-GG haplotype was found more frequently in advanced progressors than in LTNPs (P = 0.02). CONCLUSION: TRIM22 genetic diversity affects HIV-1 replication in vitro and it is a potentially novel determinant of HIV-1 disease severity.


Subject(s)
HIV Infections/genetics , HIV-1/genetics , Polymorphism, Single Nucleotide/genetics , Repressor Proteins/genetics , Adult , Disease Progression , Female , Haplotypes , Humans , Male , Middle Aged , Minor Histocompatibility Antigens , Transcription, Genetic , Tripartite Motif Proteins , Virus Replication
18.
Onderstepoort J Vet Res ; 79(1): E1-8, 2012 Dec 07.
Article in English | MEDLINE | ID: mdl-23327326

ABSTRACT

A survey amongst sheep and goat producers and veterinarians was undertaken to collect epidemiological data on orf in South Africa. Previous epidemiological studies on the presence of the disease in the country have not been documented and this report is the first descriptive epidemiological study of orf in South Africa. A seven-month investigation, realised by direct and indirect interviews and field observation, enabled us to outline incidence and risk factors of this disease and to better understand how the local farmers in rural areas relate to it. The results may contribute to better management of the disease in rural areas. By means of molecular analyses the phylogenetic relationships between field isolates from different areas have been identified. The findings gave a first important contribution to the general assessment of the economic impact of orf virus infections and the extent of the risk to human health.


Subject(s)
Ecthyma, Contagious/epidemiology , Orf virus/classification , Phylogeny , Animals , Humans , Orf virus/isolation & purification , Public Health , Risk Factors , Sheep , South Africa/epidemiology , Zoonoses
19.
Emerg Infect Dis ; 17(4): 684-7, 2011 Apr.
Article in English | MEDLINE | ID: mdl-21470460

ABSTRACT

To characterize parapoxviruses causing severe disease in wild ruminants in Stelvio Park, Italy, we sequenced and compared the DNA of several isolates. Results demonstrated that the red deer isolates are closely related to the parapox of red deer in New Zealand virus.


Subject(s)
Deer/virology , Parapoxvirus/genetics , Poxviridae Infections/veterinary , Animals , Italy , Parapoxvirus/classification , Phylogeny , Poxviridae Infections/virology , Sequence Analysis, DNA , Viral Envelope Proteins/genetics
20.
J Clin Virol ; 48(1): 69-72, 2010 May.
Article in English | MEDLINE | ID: mdl-20207192

ABSTRACT

BACKGROUND: Occupational exanthematic diseases represent an important cause of public health impact and economical losses. Among the viral exanthematic diseases, two caused by poxviruses are noteworthy: the bovine vaccinia (BV), caused by the Vaccinia virus (VACV); and the milker's nodule, in which the agent is the Pseudocowpox virus (PCPV). Both agents are zoonotic and have been associated with several cases of bovine infection. In Brazilian rural areas BV has been highly prevalent, particularly in milk herds. Farmers, milkers and their close contacts developed lesions on the hands, forearms, legs and face accompanied by several systemic symptoms. Although VACV and PCPV present with similar epidemiological and transmission patterns, no VACV and PCPV co-infection cases have to date been described. OBJECTIVES: To describe the first case of zoonotic VACV and PCVP co-infection, based on serological and molecular methods. STUDY DESIGN AND RESULTS: In this work we report a case of a Brazilian rural worker who presented with a large severely ulcerated-pustule skin lesion, associated with fever, headache, malaise, myalgia and axillary, inguinal and cervical limphadenopathy. The worker declared occupational contact with cattle that had notable injuries on their teats. Human and bovine clinical samples were collected and submitted to serological and molecular tests. PCR and phylogenetic analysis revealed the presence of VACV DNA and PCPV DNA in the patient's lesion. Serological tests indicated anti-VACV neutralizing antibodies and molecular assays showed the presence of VACV and PCPV DNA in the patient sera. VACV and PCPV also were detected in dairy cattle. CONCLUSION: Together, these results indicate a case of zoonotic VACV/PCPV co-infection. Epidemiological surveillance and appropriate medical treatment are essential for the control of both diseases, especially in the most severe cases, as described in the present study.


Subject(s)
Poxviridae Infections/virology , Pseudocowpox Virus/genetics , Vaccinia virus/genetics , Vaccinia/virology , Zoonoses/virology , Animals , Brazil , Cattle , Fingers/pathology , Fingers/virology , Humans , Male , Phylogeny , Poxviridae Infections/diagnosis , Skin/pathology , Skin/virology , Young Adult
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