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I Abbate

Publications and source records attributed to I Abbate.

At least 19 recordsLinked to original sources
PubMed2006

Influence of GBV-C infection on the endogenous activation of the IFN system in HIV-1 co-infected patients.

BACKGROUND: GB virus C (GBV-C) co-infection is associated with a better prognosis in HIV-infected persons. Since interferon activation can be one of the possible mechanisms involved in GBV-C-driven protection against HIV, we compared the endogenous activation of the interferon system in PBMC from GBV-C-positive and -negative patients infected with HIV-1. METHODS: The expression of interferon related genes was analyzed in 20 GBV-C positive and 20 GBV-C-negative HIV-infected patients, comparable in terms of CD4 cell counts and HIV viral loads. The levels of mRNA for interferon-related genes (2-5-OAS, MxA, interferon AR-1 and PKR) in PBMC were measured by real time RT-PCR, using B-actin as internal control. RESULTS: The endogenous levels of all the Interferon-related genes in HIV/GBV-C co-infected patients were higher than in HIV mono-infected subjects. The difference was statistically significant for PKR mRNA. Direct positive correlation was found between PKR and all the other interferon-related genes, suggesting a coordinated activation of the interferon system. CONCLUSIONS: Enhanced activation of the interferon system occurs in GBV-C-positive, as compared to GBV-C-negative patients harbouring HIV-1. These data may be relevant to understand the GBV-C-driven protection against HIV, suggesting that the endogenous activation of the interferon system can contribute to the control of HIV replication.

2',5'-Oligoadenylate Synthetase↗
PubMed2004

Expression of Werner and Bloom syndrome genes is differentially regulated by in vitro HIV-1 infection of peripheral blood mononuclear cells.

In HIV infection, continuous immune activation leads to accelerated ageing of the adaptive immune system, similar to that observed in elderly people. We investigated the expression of WRN and BLM (genes involved in disorders characterized by premature ageing, genomic instability and cancer predisposition) in peripheral blood mononuclear cells (PBMC) activated in vitro with phytohaemagglutinin (PHA) and infected with different HIV-1 strains. The steady state levels of mRNA were analysed by reverse transcription-polymerase chain reaction (RT-PCR), and protein expression was assayed using immunocytochemistry and Western blot techniques. In uninfected PBMC, PHA stimulation induced an increase in BLM mRNA and protein expression, while WRN expression remained virtually unchanged. When PBMC were infected in vitro with a lymphotropic HIV-1 strain, the level of BLM mRNA showed a peak at 24 h of infection, followed by a decline to uninfected culture levels. A similar result failed to be seen using an R5-tropic HIV-1 strain. In accordance with mRNA expression, in HIV-infected cultures PBMC were stained more frequently and more intensely by a BLM-specific antibody as compared to uninfected cultures, staining peaking at 24. Conversely, WRN expression was not modulated by HIV-1. The proportion of cells showing BLM up-regulation, established by immunocytochemical staining, was much greater than the proportion of productively infected PBMC, as established by proviral DNA measurement. This result indicates that BLM up-regulation is probably a result of an indirect bystander cell effect. Activation of the BLM gene in infected PBMC suggests that premature ageing could be a further immunopathogenetic mechanism involved in HIV-induced immunodeficiency, and points to a possible new candidate target for innovative therapeutic intervention.

Adenosine Triphosphatases↗
PubMed2001

Changes in host cell molecules acquired by circulating HIV-1 in patients treated with highly active antiretroviral therapy and interleukin-2.

OBJECTIVE: To analyse cell membrane proteins (CMP) acquired by HIV-1 present in the plasma of asymptomatic patients, and their modifications after a cycle of highly active antiretroviral therapy (HAART) and interleukin (IL)-2. DESIGN AND METHODS: Plasma samples from eight drug-naive asymptomatic subjects underwent immobilized antibody capture (IAC) to detect CMP on the surface of circulating HIV-1. The CMP considered were lymphocyte subset markers (CD45RA, CD45RO), activation markers (HLA-DR), adhesion molecules (LFA-3), costimulatory proteins (B7-2), lymph-node homing receptors (CD62L) and pro-apoptosis molecules (FasL). This analysis was repeated after one cycle of HAART + IL-2, after virus rebound. RESULTS: LFA-3, followed by CD45RO and HLA-DR, are the most represented CMP on the surface of circulating virions in naive asymptomatic patients; CD45RA, CD62L, B7-2 and FasL are detected only occasionally. After rebound, a significant reduction of CD45RO and HLA-DR, but not of LFA-3, is observed on virions, whereas CD45RA and CD62L, as well as other molecules, are not affected, remaining almost undetectable. CONCLUSIONS: Assuming that CMP on HIV-1 reflect the cellular origin of virions, activated T cells expressing CD45RO, HLA-DR, and LFA-3 may be the main source of HIV-1 in asymptomatic patients. After a cycle of HAART + IL-2, followed by therapy interruption, CD45RA and CD62L are detected on virions rarely, indicating that even during virus rebound, expanded naive T cells do not become a major target of virus replication. Furthermore, the presence of HLA-DR on rebound HIV-1 is decreased, consistent with decreased activation of the HIV-producing cells. More extensive investigation may clarify the significance of these findings with respect to pathogenesis.

Anti-HIV Agents↗
PubMed2000

Activation of signal transduction and apoptosis in healthy lymphomonocytes exposed to bystander HIV-1-infected cells.

Persistent activation of the immune system is one of the hallmarks of HIV-1 infection. In this study we analysed the induction of factors involved in cytokine signal transduction, such as STAT 1 proteins and IRF-1 mRNA, in normal peripheral blood mononuclear cells (PBMC) exposed to HIV-infected cells, and the induction of apoptosis. Western blot analyses and reverse transcriptase-polymerase chain reaction results indicate that both cells infected with a X4 strain and cells infected with a R5 strain are able to increase intracellular levels of STAT 1alpha and beta proteins as well as IRF-1 mRNA. This effect was prevented by neutralizing antibodies against interferon-alpha (IFN-alpha). HIV-1-infected cells dose-dependently induced apoptotic commitment in normal PBMC, as revealed by DNA fragmentation analysis, but this was not accompanied by an increase of caspase-3 activity, even if a slight up-regulation of IL-1beta-converting enzyme mRNA was detected. Apoptosis induction could be abrogated mainly by antibodies against tumour necrosis factor-alpha (TNF-alpha) and, to a lesser extent, by antibodies against IFN-gamma. All these findings suggest that uninfected PBMC can undergo activation of signal transduction and apoptosis after exposure to bystander HIV-infected cells, subsequent to the induction of cytokines such as IFNs and TNF-alpha.

Apoptosis↗
PubMed1999

RANTES stimulates cell-mediated transmission of HIV-1 infection.

We wished to determine the effects of the beta-chemokine RANTES in an established system of cell-mediated transmission of HIV-1, that is, normal human umbilical vein endothelial cells (HUVEC) nonproductively infected with HIV-1, cocultivated with CD4+ T cells to rescue productive infection. The results indicate that the addition of RANTES to HUVEC, either before or after HIV-1 infection, stimulates HIV-1 rescue by CD4+ T cells. However, viral DNA is not increased in HUVEC, suggesting that the stimulation exerted by RANTES could be mediated by events following HUVEC infection. The mechanisms of increase seem to be related to the rescue phase, involving membrane interaction of abortively infected HUVEC with permissive T cells. In fact, a strong upregulation and polarization of intercellular adhesion molecule-1 (ICAM-1) is induced in HUVEC by RANTES, and antibodies against ICAM-1 inhibit HIV-1 rescue by T cells. These results indicate that RANTES, similarly to other inflammatory cytokines, may favor HIV-1 spreading and crossing of blood-tissue barriers by indirect mechanisms involving membrane interactions between nonproductively infected and permissive cells.

Acquired Immunodeficiency Syndrome↗
PubMed1999

Effects of the human CD38 glycoprotein on the early stages of the HIV-1 replication cycle.

CD38 displays lateral association with the HIV-1 receptor CD4. This association is potentiated by the HIV-1 envelope glycoprotein gp120. The aim of this work was to evaluate the CD38 role in T cell susceptibility to HIV-1 infection. Using laboratory X4 HIV-1 strains and X4 and X4/R5 primary isolates, we found that CD38 expression was negatively correlated to cell susceptibility to infection, evaluated as percentage of infected cells, release of HIV p24 in the supernatants, and cytopathogenicity. This correlation was at first suggested by results obtained in a panel of human CD4(+) T cell lines expressing different CD38 levels (MT-4, MT-2, C8166, CEMx174, Supt-1, and H9) and then demonstrated using CD38 transfectants of MT-4 cells (the line with the lowest CD38 expression). To address whether CD38 affected viral binding, we used mouse T cells that are non-permissive for productive infection. Gene transfection in mouse SR.D10.CD4(-).F1 T cells produced four lines expressing human CD4 and/or CD38. Ability of CD4(+)CD38(+)cells to bind HIV-1 or purified recombinant gp120 was significantly lower than that of CD4(+)CD38(-) cells. These data suggest that CD38 expression inhibits lymphocyte susceptibility to HIV infection, probably by inhibiting gp120/CD4-dependent viral binding to target cells.-Savarino, A., Bottarel, F., Calosso, L., Feito, M. J., Bensi, T., Bragardo, M., Rojo, J. M., Pugliese, A., Abbate, I., Capobianchi, M. R., Dianzani, F., Malavasi, F., and Dianzani, U. Effects of the human CD38 glycoprotein on the early stages of theHIV-1 replication cycle.

ADP-ribosyl Cyclase↗
PubMed1999

Cisplatin, interleukin-2, interferon-alpha and tamoxifen in metastatic melanoma. A phase II study.

PURPOSE: To evaluate the efficacy and toxicity of an immuno-hormonal-chemotherapeutic combination of cisplatin, interleukin-2, interferon-a and tamoxifen in metastatic malignant melanoma. PATIENTS AND METHODS: Fifteen consecutive patients were treated with cisplatin at a dose of 100 mg/m2 on day 1, interleukin-2 subcutaneously at a dose of 18 MU from days 3-6 and from days 17-21, interferon-a 2-b subcutaneously at a dose of 3 MU three times weekly and tamoxifen orally at a dose of 20 mg daily. The cycle was repeated on day 28. Patients were evaluated after two cycles. Patients with progressive disease stopped the treatment while responding patients and those with stable disease underwent two further cycles. No maintenance regimen was employed. RESULTS: Two partial remissions (PR, 13%), 5 stable disease (SD, 33%) and 8 progression disease (PD, 53%) were observed. Patients with PR and SD had better survival than those with PD (11 vs 6 months). Toxicity was predominantly fever and vomiting besides chills, fatigue and flu-like syndrome, normally related to cytokine administration and often influencing the quality of life. CONCLUSIONS: Our results, unlike the good results of previous trials, are very poor. Therefore we do not recommend this combination for routine treatment of advanced melanoma.

Adult↗
PubMed1998

Inhibition of HIV type 1 BaL replication by MIP-1alpha, MIP-1beta, and RANTES in macrophages.

The beta-chemokines RANTES, MIP-1alpha, and MIP-1beta have been shown to inhibit the infection of T cells by macrophage-tropic HIV-1 strains by blocking env-driven HIV-1 fusion through competition for the chemokine receptors or receptor downregulation. This study was aimed at testing whether beta-chemokines also inhibit the productive infection of monocyte-derived macrophages (MDMs) by a monocytotropic HIV-1 strain, by using virus yield assays. The action of the beta-chemokines MIP-1alpha, MIP-1beta, and RANTES was captured with that of the alpha-chemokine interleukin 8 (IL-8) and of interferon alpha (IFN-alpha), which is a well-known broad-range inhibitor of viral replication. While IL-8 did not inhibit HIV-1 BaL replication in MDMs, the beta-chemokines were dose-dependently inhibitory. RANTES was the most effective, reaching at 300 ng/ml a protection similar to that obtained with IFN-alpha at 1000 IU/ml, and was even more inhibitory when added to MDMs after virus attachment. In contrast to IFN-alpha, the antiviral activity of beta-chemokines was restricted to HIV, because another virus was not inhibited. As compared with untreated MDMs, full-length proviral DNA at day 1 postinfection was inhibited in MDMs treated with RANTES either before or after the absorption phase, and even more so in IFN-treated MDMs, whereas in IL-8-treated MDMs no inhibition was observed. Our results indicate that in MDMs both RANTES and IFN affect early steps of HIV-1 BaL replication, preceding the completion of viral DNA synthesis.

Anti-HIV Agents↗
PubMed1995

Antibody to ICAM-1 mediates enhancement of HIV-1 infection of human endothelial cells.

Human umbilical vein endothelial cells (HUVEC) can be abortively infected with HIV-1, but virus production is rescued by the addition of T cells. Monoclonal antibody (Mab) to ICAM-1, but not its Fab' fragment or MAbs to LFA-1 and PECAM-1, increases HIV-1 infection of HUVEC by enhancing HIV-1 absorption. Enhancement by anti ICAM-1 is probably due to a bridging effect different from the ADE mediated by anti-gp120 that involves FcR or CR-mediated capture of the virus-antibody complex. Since antibodies to cell membrane molecules are present in HIV-1 infected patients, the ADE mediated by such a mechanism can be important in AIDS pathogenesis.

Antibodies, Monoclonal↗
PubMed1995

Host cell antigenic profile acquired by HIV-1 is a marker of its cellular origin.

HIV-1 acquires cell membrane proteins during budding. The cell membrane proteins (CMP) profile of laboratory HIV-1 strains grown in different host cells was established, by using an immobilized antibody capture (IAC), to verify whether CMPs present on HIV-1 correlate with its host cell origin. HIV-1 grown in different cell lines incorporates cell markers such as CD3, CD19, CD14, CD31 and IL 2-R, according to the distinctive expression of these antigens on the host cells. Furthermore, also T-tropic and monocytotropic HIV-1 strains display host cell specific markers, supporting the hypothesis that virus associated CMPs are a marker of host cell origin.

Antigens, CD↗
PubMed1995

Simultaneous determination of pseudouridine, neopterine and creatinine in urine by ion-pair high-performance liquid chromatography with in-series ultraviolet and fluorescence detection.

A simple, fast and precise method for the simultaneous determination of neopterine (Npt), pseudouridine (Psu) and creatinine (Cre) in urine by using ion-pair HPLC has been developed. The urine specimen is subjected to a microcolumn clean-up step, providing a ten-fold sample dilution, and is then injected into the column. The eluate is forced through the respective cells of a fluorescence and then a UV detector, which are connected in series. Neopterine is monitored by fluorescence emission at 438 nm (excitation wavelength 353 nm) while Psu and Cre are monitored by UV absorption at 235 nm. This allows the determination of Npt/Cre and Psu/Cre concentration ratios in a single run on the same sample, and the use of urine specimens collected randomly instead of 24 hourly collections. The method has been applied to urine specimens from 19 healthy, male donors (mean Npt/Cre (mumol/mol) and Psu/Cre (mumol/mmol) values of 41.7 and 16.8, respectively) and 23 healthy, female donors (mean Npt/Cre (mumol/mol) and Psu/Cre (mumol/mol) values of 67.4 and 18.5, respectively). The within-run S(r) for Npt/Cre and Psu/Cre concentration ratios ranged between 3.3 and 4.6%.

Adult↗
PubMed1995

HIV type 1 grown on interferon gamma-treated U937 cells shows selective increase in virion-associated intercellular adhesion molecule 1 and HLA-DR and enhanced infectivity for CD4-negative cells.

Cellular adhesion molecules, such as ICAM-1, -2, and -3; LFA-1; and HLA class I and II are incorporated into HIV-1 virions during budding from infected cells. These virion-associated molecules can be involved in the adsorption to susceptible cells displaying the corresponding counterligands. A number of cytokines have been shown to upregulate the cellular expression of adhesion molecules, such as ICAM-1 and HLA-DR. In this study we investigated the effects of IFN-gamma on the incorporation of ICAM-1, LFA-1, and HLA-DR into mature HIV-1 progeny from chronically infected cells. The ability of such virus progeny to infect either CD4-positive or -negative cells was also investigated. The results indicate that IFN-gamma stimulates the expression of ICAM-1 and of HLA-DR on HIV-1-infected cells, whereas LFA-1 expression is unaffected. The same modifications were also observed on virus progeny, because specific MAbs to ICAM-1 and HLA-DR captured infectious HIV-1 from IFN-treated cells with higher efficiency as compared to virus from control cells, whereas virus binding to anti LFA-1 MAb was unchanged. Moreover, the HIV-1 progeny released from IFN-treated cells showed an increased ability to bind to and to infect CD4-negative cells, whereas the infectivity was basically unchanged for CD4-positive cells. Our results suggest that cytokines, as well as other soluble factors, may expand the host cell range of HIV-1, possibly through modifications of the cell-derived surface molecules on the virions.(ABSTRACT TRUNCATED AT 250 WORDS)

CD4 Antigens↗
PubMed1995

Long-term subcutaneous recombinant interleukin-2 as maintenance therapy: biological effects and clinical implications.

Several trials have evaluated the therapeutic efficacy of rIL-2 combined with more traditional treatments such as chemotherapy and radiotherapy, but the use of IL-2 as adjuvant therapy for minimal residual disease or to maintain clinical response obtained with other standard treatments has yet to be investigated. The aim of the present trial was to study the biological effects of maintenance long-term treatment (6 months) with subcutaneous low-dose IL-2 in 16 patients with different neoplasms previously treated with chemo-immuno therapeutic regimens or with surgery (7 metastatic renal cancers, 5 locally advanced renal cancers previously subjected to radical nephrectomy, 2 metastatic breast cancers, 1 small cell lung cancer, and 1 metastatic melanoma). Clinical tolerability, feasibility and therapeutic implications are also discussed. The IL-2 schedule was as follows: 4.5 million IU/day, 3 times weekly for 6 months. A total of 14 patients completed therapy without requiring dose modifications and are free of progression after a median duration of 8+ months (range: 7+ to 34+) while two patients progressed during therapy (one inflammatory breast cancer and one renal cancer). Important and persistent hemato-immunostimulating effects in both soluble (IL-2, sIL-2R, IL-6) and cellular (lymphocyte subsets, monocytes, eosinophils) parameters were noted during the entire treatment. The IL-2 related toxicity was quite low. Moreover, this long-term IL-2 therapy could control neoplastic growth and thus prolong clinical response obtained with standard treatments. Prospective randomized studies regarding the clinical efficacy have been initiated.

Aged↗
PubMed1995

Unidirectional budding of HIV-1 at the site of cell-to-cell contact is associated with co-polarization of intercellular adhesion molecules and HIV-1 viral matrix protein.

OBJECTIVES: To explore the possibility that HIV-1 budding and cellular adhesion molecules co-polarize at cell-to-cell contact sites. To investigate the incorporation of host-cell-derived adhesion molecules into HIV-1. METHODS: The cellular sites involved in HIV-1 budding were examined by transmission electron microscopy. Single and double immunocytochemistry staining was used to evaluate the cellular distribution of the viral matrix protein and adhesion molecules. Quantitative flow cytometry was used to measure the cellular expression of adhesion molecules. An immunocapture technique was used to measure the presence of cell-derived proteins on HIV-1. The captured virus was measured by a p24 antigen assay. The infectivity of virus captured by monoclonal antibodies was tested by measuring the virus antigen yield in supernatants after the addition of sensitive cells. RESULTS: Released and budding HIV-1 was mainly localized at the cell-to-cell contact regions. This feature was consistent with a polarized staining for the virus matrix protein p18 at cell-to-cell contact regions. Intercellular adhesion molecules (ICAM)-1 in HIV-1-infected cells were polarized on both isolated cells and syncytia, co-localizing with HIV-1 matrix protein. HIV-1 incorporated all the adhesion molecules expressed by the host cells, although without quantitative correlation with their cellular expression. CONCLUSIONS: HIV-1 is released at cell-to-cell membrane contact sites. Both ICAM-1 and virus matrix protein co-polarized on isolated cells and syncytia at the sites involved in the recruitment of uninfected cells. The impressive concentration of ICAM at cell sites where most virions are released may account for the acquisition of these membrane proteins by the HIV-1 progeny, and may be important for the cell-mediated spread.

Antigens, CD↗
PubMed1995

Ovarian fibroma. A report of three cases.

The authors report three cases of ovarian fibroma in women in advanced menopause (mean age: 70 years). The neoplasm was bilateral in one patient. Early symptoms were pelvic pain, and, in one patient, menorrhagia without histologic alterations of the atrophic endometrium. The histology was typical of ovarian fibromas, except for one case which was characterized by a dense pseudofibrosarcomatous pattern and by the presence of numerous sex cord elements.

Aged↗
PubMed1994

Solitary plasmacytoma of bone and extramedullary plasmacytoma: two different nosological entities?

BACKGROUND: The relationship between solitary plasmacytoma and multiple myeloma is still unclear, but they can be distinguished by their different clinical course. Indicators of disease activity and extension, and of a possible evolution to multiple myeloma, have not been identified as yet. METHODS: Two cases of solitary plasmacytoma are described: one of the mandible and one extramedullary plasmacytoma (EMP) of the rhinopharynx. Pathologic data included immunohistochemical staining for heavy and light Ig chains, and for the proliferating cell nuclear antigen (PCNA). Analysis of the peripheral immunological status and serum parameters (beta 2 microglobulin, thymidine kinase, IL-2, IL-6 and soluble IL-2 receptor) was performed and correlation was made with the clinical status. Flow cytometry analysis of nuclear DNA content and S-phase cell fraction were also studied in both neoplasms. RESULTS: Solitary plasmacytoma of bone (SPB) showed important basal immunologic alterations and a marked increase in all serum parameters considered with respect to EMP. Ploidy analysis demonstrated an almost complete aneuploidy cell population for the SPB patient (80%), whereas in the EMP patient only 2% of the cells were aneuploid. The S-phase cells were 16% and 4%, respectively. PCNA index was 60% in SPB and 10% in EMP. CONCLUSIONS: Solitary plasmacytoma of the bone appeared to be a more aggressive form of plasmacellular neoplasia, distinct from EMP and similar to multiple myeloma. The study of serum parameters, together with analysis of PCNA, ploidy and S-phase fraction, can aid in better understanding disease activity, and in the choice of more adequate treatment. Moreover, serial analysis of some serum factors might be useful markers for monitoring the disease.

Aged↗