Biomedical subjects

Mara Biasin

Publications and source records attributed to Mara Biasin.

11 recordsLinked to original sources

PubMed2006

Thalidomide in the treatment of chronic hepatitis C unresponsive to alfa-interferon and ribavirin.

Immunomodulation of thalidomide is represented by the antiinflammatory effect through inhibition of tumor necrosis factor alpha and costimulatory effect on human CD8+ T cells. We investigated the efficacy and safety of a 24-wk course of thalidomide at a dosage of 200 mg/day in eight patients with HCV chronic hepatitis nonresponders to interferon alpha plus ribavirin. We observed a significant mean decrease of serum aminotransferases and gamma-glutamyltransferases of 39% and 61%, respectively (p = 0.017 and 0.02). Tumor necrosis factor-alpha in vitro production in mononuclear cells decreased with thalidomide in all the subjects (p = 0.028). Perforin- and granzyme-specific mRNA expression increased under thalidomide without statistical significance. A positive correlation between biochemical and immunological parameters was observed with higher increase of granzyme and perforin values in patients showing reduction of aminotransferases. Finally upregulation of T-helper 1 cytokine expression as mean interferon gamma/IL-10 ratio was evidenced. Thalidomide was well tolerated. In conclusion, thalidomide was able to reduce liver enzymes in six out of eight patients with chronic hepatitis C and to reduce tumor necrosis factor alpha production, representing a promising new approach for the treatment of HCV infection.

Adult↗

PubMed2005

Decrease in pathology and progression of scrapie after immunisation with synthetic prion protein peptides in hamsters.

Effective therapy for prion diseases is currently unavailable. Recently, vaccination was shown to be effective in mouse models of a particular neurodegenerative conditions: Alzheimer's disease (AD). Here, we report that vaccination with synthetic oligopeptides homologous to the hamster (Mesocricetus auratus) prion protein augments survival time in animals infected intraperitoneally with 263K scrapie agent. For each hamster included in the study, prion-specific serum antibodies as well as deposition of pathological prion protein (PrP(res)), glial fibrillary acidic protein (GFAP), and mRNA expression for cytokines (TNF alpha, IL-1beta, IL-10) in brain tissues were evaluated. In immunized animals, increased survival after challenge was associated with a reduction of cerebral lesion, PrP deposition and GFAP expression; in these animals, anti-prion protein peptide antibody levels were increased, and the expression of pro-inflammatory cytokines (TNF alpha and IL-1beta) was reduced. Vaccination could be an effective therapeutic approach to postpone disease onset.

Amino Acid Sequence↗

PubMed2004

Human alpha defensin in HIV-exposed but uninfected individuals.

Human alpha defensins 1, 2, and 3 are produced by CD8 T cells of HIV-infected long-term nonprogressors and have an antiviral activity. alpha 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 alpha defensin production and alpha defensin-expressing CD8 lymphocytes were comparable in ESNs and HIV patients, constitutive alpha defensin production by peripheral CD8 and CVMCs was augmented in ESNs compared with HCs (P = 0.001 and P = 0.058, respectively); alpha defensin mRNA was increased in PBMCs of ESNs; unstimulated, alpha 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 alpha defensin mRNA and alpha 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 alpha defensin is seen in HIV-exposed uninfected individuals; these peptides could have a role in the potentially protective immune response that characterizes ESNs.

Biopsy↗

PubMed2004

Granule-dependent mechanisms of lysis are defective in CD8 T cells of HIV-infected, antiretroviral therapy-treated individuals.

BACKGROUND: HIV-specific cytotoxic T-cell (CTL) responses are defective in HIV-infected patients undergoing antiretroviral therapy (ART). This defect has been attributed to the decreased antigenic burden secondary to ART-associated suppression of HIV-replication, and is responsible for the rebounds of viraemia that occur when patients interrupt therapy. CTL are stimulated by type 1 cytokines and can kill targets via granule-dependent (perforin and granzymes) and -independent (tumour necrosis factor-alpha, CD95) mechanisms. METHODS: Granule-dependent and granule-independent mechanisms of CTL killing, as well as type 1 cytokine production by CD4 T cells, were analysed in 57 chronically HIV-infected ART-treated or ART-untreated individuals. RESULTS: The results can be summarized as follows: the frequency of gp160 (env)-specific interferon-gamma-secreting CD8 T lymphocytes correlates positively with HIV viraemia in ART-treated and -untreated patients; Env-specific perforin- and granzymes-expressing CD8 T lymphocytes, and Env-stimulated perforin and granzymes mRNA, are reduced in ART-treated patients independently of HIV viral load and of type 1 cytokine production; tumour necrosis factor-alpha production is increased in ART-treated individuals; and Env-specific immature CD8+28+27+ cells are only marginally augmented in ART-treated patients, Similar results are observed in cytomegalovirus-specific CD8 T cells and peripheral blood mononuclear cells. CONCLUSIONS: A defect of CTL function that selectively affects the granule-dependent mechanisms of lysis is observed in ART-treated individuals. Because interferon-gamma production is higher in these patients, this could be a defect primarily involving CTL. These data suggest an independence of CD8 T-cell numbers and their lytic ability in HIV-infected, ART-receiving patients. Immunomodulants are needed to successfully treat HIV infection.

Adult↗

PubMed2004

Immunomodulation induced by tucaresol in HIV infection: results of a 16 week pilot Phase I/II trial.

OBJECTIVE: Immune reconstitution in highly active antiretroviral therapy (HAART)-treated individuals is incomplete and immunomodulatory compounds are needed to improve the outcome of HIV therapy. In a Phase I/II clinical trial performed on HIV-positive patients we analysed the safety and immunomodulating effects of tucaresol, a novel compound that has previously been described tn enhance cell-mediated immune responses. PATIENTS AND METHODS: Sixteen weeks pulse dose escalation protocol. Four groups of HIV-positive patients were enrolled: group A (n=6): HAART, CD4+ 300-500 cells/microl, HIV RNA <80 copies/ml; group B (n=6): HAART-naive, CD4+ <500 cells/microl, HIV RNA >10 000 copies/ml; group C (n=3): HAART-naive, CD4+ >500 cells/microl, HIV RNA <10000 copies/ml; and group D (n=6): HAART, CD4+ <200cells/microl, HIV RNA <80 copies/ml. Tucaresol was added to HAART in group A and D patients; group B patients started tucaresol with HAART, group C patients received tucaresol alone. Clinical and immunological analyses were performed at different time points. RESULTS: Tucaresol-related serious adverse events were observed in the first week of therapy in 2/21 patients who were viraemic when commencing treatment, but did not occur in patients on stable HAART. Tucaresol did not affect HIV viraemia whereas increases in CD4+ percentages, mainly supported by naive CD4+ cells, were observed. CD8+/28-/45RA+ cells and HIV-specific CD8+ IFNgamma- and perforin-producing cells improved whereas IL-10 mRNA diminished in tucaresol-treated patients. The effects were greater with 25 mg given every other day for 1 week. CONCLUSION: In HAART-receiving patients with proper virus suppression, tucaresol was not associated with serious adverse events and resulted in qualitative and quantitative stimulation of HIV-specific cytotoxic T lymphocyte activity and generation of naive T cells. These data may support further exploration of tucaresol use in reconstitution of immune system parameters in HIV patients with proper virus suppression while on HAART.

Adult↗

PubMed2003

Functional repertoire of dendritic cells generated in granulocyte macrophage-colony stimulating factor and interferon-alpha.

Monocyte-derived dendritic cells (DCs) generated in granulocyte macrophage-colony stimulating factor (GM-CSF) and interleukin-4 (IL-4-DCs) are used to enhance antitumor immunity in cancer patients, although recent evidence suggests that their functional repertoire may be incomplete; in particular, IL-4-DCs appear unable to induce type 2 cytokine-producing T helper (Th) cells. To assess whether type 1 interferon (IFN) could replace IL-4 and generate DCs with a more complete repertoire, we characterized in detail DCs generated from human monocytes cultured with GM-CSF and IFN-alpha (IFN-DCs). We found that IFN-alpha induces DC differentiation more efficiently than IL-4, yielding similar numbers of DCs in a shorter time and that this differentiation persists upon removal of cytokines. Although IFN-DCs had a more mature immunophenotype than IL-4-DCs, showing higher expression of CD80, CD86, and CD83, they still preserved comparable endocytic and phagocytic capacities and responsiveness to maturation stimuli. IFN-DCs had strong antigen-presenting capacity, inducing intense proliferation of T cells to alloantigens or influenza virus. Moreover, IFN-DCs produced lower levels of IL-12p70 and higher levels of IFN-alpha, IL-4, and IL-10 than IL-4-DCs. As a consequence of this different pattern of cytokine secretion, IFN-DCs induced T cells to produce type 1 (IFN-gamma) and type 2 (IL-4 and IL-10) cytokines, and as expected, IL-4-DCs induced only Th1 differentiation. As immune responses with extreme Th1 bias are considered inadequate for the induction of optimal, systemic antitumor immunity, the ability of IFN-DCs to promote more balanced cytokine responses may suggest the advisability to consider these cells in the development of future, DC-based immunotherapy trials.

Cell Adhesion↗

PubMed2003

IL-4 and CXCR4 upregulation in HIV-infected and uninfected individuals from Maharashtra-Mumbai.

We extended the investigation of the virus-host interaction in developing countries by analysing Indian HIV-infected and uninfected individuals from Maharashtra-Mumbai. Results showed that CXCR4 messenger RNA and surface expression, as well as IL-4 mRNA and T allele frequency at the -589 site in the IL-4 gene (high IL-4 production) were significantly increased in Indian compared with Italian individuals. Because IL-4 stimulates CXCR4 expression this observation could be explained by the higher frequency of the -589T IL-4 polymorphism.

CD4-Positive T-Lymphocytes↗

PubMed2002

B7-H1 is up-regulated in HIV infection and is a novel surrogate marker of disease progression.

The ligation of programmed death-ligand 1 (B7-H1) to T cells results in the preferential production of interleukin 10 (IL-10). We investigated if B7-H1 would be up-regulated in HIV infection, a disease characterized by increased IL-10 production, by measuring B7-H1, B7-1 (CD80), and B7-2 (CD86) expression and mRNA in 36 HIV-infected patients and in 22 healthy controls (HCs). Results showed that (1) B7-H1 expression and mRNA are augmented in cells of HIV patients; (2) increased IL-10 production in these patients is largely induced by B7-H1-expressing CD14(+) cells; (3) an inverse correlation is detected between B7-H1 expression and CD4 counts, whereas the up-regulation of B7-H1 is directly associated with HIV plasma viremia; (4) antiviral therapy results in the parallel down modulation of IL-10 production and B7-H1 expression/synthesis; and (5) B7-H1/CD80 and B7-H1/CD86 mRNA ratios are increased in peripheral blood mononuclear cells (PBMCs) of HIV patients compared with HCs. B7-H1 synthesis and expression are up-regulated in HIV infection, and the degree of dysregulation correlates with the severity of disease. Aberrant antigen presentation by antigen-presenting cells (APCs) that exhibit increased B7-H1 expression and IL-10 production in HIV infection could be responsible for T-lymphocyte unresponsiveness and loss of protective immunity. B7-H1 is a surrogate marker potentially involved in AIDS disease progression.

Antigens, CD↗

PubMed2002

AIDS in Africa.

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Disease Susceptibility↗

PubMed2002

Serum concentration of gammaGT is a surrogate marker of hepatic TNF-alpha mRNA expression in chronic hepatitis C.

Serum gammaGT levels and hepatic expression of tumor necrosis factor-alpha (TNF-alpha) are host factors that can independently predict the outcome of interferon (IFN) treatment in patients with chronic hepatitis C virus (HCV) infection. To explore whether a correlation exists between these two factors, we measured pretreatment gammaGT levels in serum and TNF-alpha mRNA levels in liver biopsies of chronic HCV patients. Seventy-two HCV patients treated with 3-to-5 million units of IFN-alpha three times a week were enrolled in the study. Treatment lasted 24 weeks and was followed by a 48-week follow-up period. Efficacy was assessed by measuring HCV RNA and alanine aminotransferase by the end of follow-up. Twelve patients (16.6%) showed a sustained biochemical and virological response. Normal pretreatment gammaGT levels, low HCV RNA titer, and infection with genotype other than HCV-1 were shown to be independent predictors of sustained response. Hepatic levels of TNF-alpha mRNA, quantified by polymerase chain reaction, were significantly higher in nonresponders (3.44 arbitrary units) compared to sustained responders (1.84 arbitrary units; P = 0.009). Values </=3.12 arbitrary units independently predicted a sustained response to IFN (P = 0.014). Finally, TNF-alpha mRNA levels were significantly correlated with serum gammaGT levels (r = 0.79, P < 0.0001). These findings suggest that serum gammaGT levels may represent a surrogate marker of hepatic TNF-alpha expression, thus explaining the importance of serum gammaGT levels in predicting treatment outcome.

Adult↗

PubMed2002

Modulation of human immunodeficiency virus (HIV)-specific immune response by using efavirenz, nelfinavir, and stavudine in a rescue therapy regimen for HIV-infected, drug-experienced patients.

Analysis of the virologic and immunomodulatory effects of an association of efavirenz (EFV), nelfinavir (NFV), and stavudine (d4T) was performed in 18 human immunodeficiency virus (HIV)-infected and highly active antiretroviral therapy (HAART)-experienced patients who failed multiple therapeutic protocols. Patients (<500 CD4(+) cells/ micro l; >10,000 HIV copies/ml) were nonnucleoside reverse transcriptase inhibitor (NNRTI)-naive and were treated for 10 months with EFV (600 mg/day) in association with NFV (750 mg three times daily) and d4T (30 or 40 mg twice daily). Measurement of HIV peptide- and mitogen-stimulated production of interleukin-2 (IL-2), gamma interferon (IFN-gamma), IL-4, and IL-10 as well as quantitation of mRNA for the same cytokines in unstimulated peripheral blood mononuclear cells were performed at baseline and 2 weeks (t1), 2 months (t2), and 10 months (t3) into therapy. The results showed that HIV-specific (but not mitogen-stimulated) IL-2 and IFN-gamma production was augmented and IL-10 production was reduced in patients who received EFV, NFV, and d4T. Therapy was also associated with a reduction in HIV RNA in plasma and an increase in CD4(+) cell count. These changes occurred in the first year of therapy (t2 and t3) and were confirmed by quantitation of cytokine-specific mRNA. Therapy with EFV, NFV, and d4T increases HIV-specific type 1 cytokine production as well as CD4 counts and reduces plasma viremia. This therapeutic regimen may be considered for use in cases of advanced HIV infection.

Adult↗