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O Pugliese

Publications and source records attributed to O Pugliese.

At least 19 recordsLinked to original sources
PubMed2001

A 5-year analysis of organ donors and recipients in Italy.

This article describes the improvement of organ donation and transplantation in Italy during 1995-1999. In 1999, the mean number of donors per million population reached 13.7 in Italy. In addition, an analysis regarding major characteristics of donors and recipients is presented, focusing particularly on donor characteristics that have changed in the past 5 years. Despite the encouraging results, further efforts are required to reach the European mean, which still remains higher than the Italian national mean. In particular, an increase of organ donation and procurement in regions with a poor activity in this field is crucial. A 1999 law on donation and transplantation should help in solving problems that continue to affect part of the nation, especially preparing the healthcare staff dedicated to organ retrieval to promote organ procurement.

Adolescent↗
PubMed2000

Short synthetic peptides derived from viral proteins compete with HIV gp120 for the binding to CD4 receptors.

In the complex mechanism of adhesion, internalization, and infection of cells by human immunodeficiency virus (HIV) viral particles, a determinant role is played by the viral envelope glycoprotein gp120, which binds to CD4 receptors of T cells and monocytes. We tested the ability of a panel of 7- to 12-residue synthetic peptides, selected from the region 414-434 of the HIV-1 gp120, to inhibit the binding of the viral protein to CD4 receptors of cultured human lymphoid cells. The assay was based on the observation that the binding of gp120 to the receptors interferes with the binding of a specific anti-CD4 monoclonal antibody, as a result of the masking of the antibody epitope; thus, we tested whether preincubation of cells with the peptides before gp120 addition might restore the recognition of the CD4 molecule by the antibody. High expression of CD4 receptors was thus assumed as indication that the binding of the viral protein had been inhibited. Maximum activity was displayed by a 9-residue peptide located near the amino terminal end of the 414-434 fragment. In addition, several fragments deduced from other viral proteins, possessing partial amino acid sequence homology with the HIV gp120 fragment, exhibited a similar type of interaction with the CD4 receptor. All active peptides contain the Cys residue (position 423 of gp120). This residue is essential, although not sufficient, for inhibiting gp120 binding, as few other amino acid residues within the fragment play a complementary role in increasing or decreasing the inhibitory ability.

Amino Acid Sequence↗
PubMed2000

[Organ donation, retrieval, and transplantation in Italy, in 1994-98].

Organ donation and transplantation activity in Italy have been always characterised by two contrasting features: first the constant positive trend in the improvement of the number of organ donors and transplants which allowed the country to exceed the value of 12 donors per million population in 1998; second the difficult situation in southern regions, so that the national distribution of the activity is highly and steadily non homogeneous. Herein we report the data regarding donation, retrievals and transplant activity in Italy in the years 1994-98, focusing on the activity of each region and the three interregional centres which encompass the majority of the national territory.

Humans↗
PubMed1999

Organ transplantation in Italy: analysis of donors and recipients.

The Istituto Superiore di Sanità (The Italian National Institute of Health) has been collecting information regarding organ donation and transplantation in Italy. Herein we describe organ procurement and transplant activity in Italy in the years 1992 1997 and show some of the characteristics regarding both donors and transplanted patients who received kidneys, hearts, livers and lungs. Although transplantation in Italy has been very difficult because of shortage of organ donors, national rates have been improving year after year. The present situation should ameliorate further to enable Italy to reach the same level of other advanced European countries.

Adolescent↗
PubMed1999

[National quality control of serologic HLA typing].

Since 1995 the Istituto Superiore di Sanità, in collaboration with the Italian Red Cross, has been organising annually the quality control of serological HLA class I and II typing on histocompatibility laboratories which perform typing for organ and bone marrow transplantation. Improvement has been obtained every year; in fact, results of the 1997 control show that the 77% of the laboratories typed the major specificities correctly. Despite the remarkable improvement achieved during the first three years of quality controls, a new organisation has been designed for further years to ensure the participation of all the Italian laboratories (more than 100) and to promote a quality control scheme that will be acceptable at international level.

Accreditation↗
PubMed1998

HIV-1 gp120 accelerates Fas-mediated activation-induced human lamina propria T cell apoptosis.

Intestinal mucosa represents an important portal of entry of HIV and a site of virus reservoir and active replication. Recently, in HIV patients, an early depletion of intestinal lamina propria T lymphocytes (LPT) has been described. HIV-1 gp120 has been demonstrated to promote apoptosis in noninfected isolated peripheral blood T cells, therefore we investigated whether gpl20 modulates apoptosis of normal human intestinal lamina propria T cells. Purified T cells were obtained by immunomagnetic negative selection from human lamina propria mononuclear cells isolated from surgical specimens by enzymatic procedure. Cells were incubated with or without recombinant gpl20 (10 microg/ml) and cultured either in the absence of any stimulus or in the presence of plate-bound anti-CD3 Ab (OKT3) or soluble anti-CD2 Ab (T11(2) + T11[3]). Apoptosis was assessed by flow cytometric analysis after propidium iodide staining. We demonstrated that preincubation of normal LPT cells with HIV-1 gpl20 accelerates the apoptosis observed during CD2-pathway stimulation of LPT cells. This process is mediated by Fas/Fas ligand interaction and related to an increased induction of Fas ligand mRNA by gpl20. Therefore HIV-1 gp120 could contribute to the depletion of noninfected LPT cells inducing a premature cell death.

Apoptosis↗
PubMed1998

Analysis of organ donation in Italy.

In 1995 the Italian Institute of Health began assembling information regarding organ donors, recipients, and transplants. Data on more than 3000 transplants were collected and recorded to date. In addition to characteristics of donors and donating hospitals, this article describes donation activity and organ procurement in Italy from 1992 to 1996. Despite the encouraging results, the donation situation in Italy remains a challenge due to the nonhomogeneous distribution of organ donation throughout the country. It is hoped that an increase in the rate of organ donation and procurement in some regions will enable Italy to reach the European mean.

Adolescent↗
PubMed1997

Apoptosis induction by human immunodeficiency virus type 1 (HIV-1) gp120 peptides.

We investigated the role of some gp120 peptides on the apoptosis induction in malignant T cell lines. We took advantage of recent findings reporting that three major regions of gp120 are important for CD4 binding. They consist of residues 256-262 in the C2 domain, residues 368-389 in the C3 domain, and residues 421-457 in C4 domain. We used a peptide from C2 domain (aa 250-263) the homologous major histocompatibility complex (MHC) class II peptide (aa 135-155) and three peptides from domain C4 (aa 414-434; 419-430; 428-445). We selected for this study the following human cell lines: CEM and Jurkat, two lymphoblastoid CD4-positive T cell line and U937, a myelomonocytic CD4 positive cell line. We demonstrated that the CD4-positive T cell lines, in the presence of gp120 250-263 peptide and DR 135-155 peptide, can be induced to accelerate apoptosis, while no effect in apoptosis induction was observed in the presence of 414-424 gp120 peptide. Interestingly, we have shown by fluorescence study, that the small sequence 414-419 must be responsible for the inhibition of binding of gp120 to the CD4 molecule. Indeed while 414-424 gp120 peptide is very efficient in CD4-gp120 binding inhibition, no effect is observed in the presence of either 419-430 or 428-445 peptide.

Amino Acid Sequence↗
PubMed1994

An HIV p24 heptapeptide down-regulates antigen-specific responses in vitro interfering at the level of the T3-Ti complex.

Ch7 (RGSDIAG), a synthetic heptapeptide derived from a conserved region of HIV p24 (aa 232-238), was previously shown to suppress antigen-induced responses in cultures of normal human peripheral blood lymphocytes (PBL). We show in this paper that Ch7 is the shortest peptide retaining full inhibitory capacity. Further, the peptide inhibited efficiently and in a dose-dependent manner the induction of a specific antibody response to the antigens SRC (sheep red cells) and Candida albicans but did not exert any effect on the induction of immunoglobulin-secreting cells in PWM-stimulated cultures. Finally, Ch7 inhibited anti-CD3-induced lymphoproliferation but did not affect anti-CD2 activation. These results suggest that a conserved epitope of HIV p24 may be able to prevent the induction of antigen-specific antibody responses by interfering with lymphocyte activation via the T3-Ti complex, resulting in the abrogation of immune functions that are defective in HIV-infected individuals.

Amino Acid Sequence↗
PubMed1994

Further evaluation of autoreactive T cells in hydatid patients.

We evaluated the peripheral autoreactive response in patients with Echinococcus granulosus who showed a negative humoral response as compared to seropositive patients and healthy controls. For this purpose, a limiting dilution analysis (LDA) of autologous mixed lymphocyte cultures was established to both estimate frequency of autoreactive T cells and, by analysing the shape of the curves, to clarify the mechanisms that underlie the autoreactive response. Different LDA curves were observed between healthy controls and patients, suggesting that different cell interactions are involved in the two populations. More interestingly, all hydatid patients, independent of their humoral response, showed a higher number of autoreactive T cells than controls. Precisely, subjects with a negative humoral response showed a range of values for autoreactive T cells exactly between the value ranges observed in seropositive and normal subjects. The present data also show that the increase of autoreactive T cells in hydatid patients correlates with the production of specific antibodies.

Adult↗
PubMed1994

Autoreactive response in seronegative homosexual men at high risk for HIV infection.

Peripheral autoreactive T cell response was evaluated by limiting dilution analysis of autologous mixed lymphocyte reaction cultures in 15 subjects at high risk for HIV infection and in 20 normal individuals. The two groups did not show a quantitative difference of peripheral autoreactive T cells, but they showed different kinetics. While controls provided a straight line passing through the origin, the majority of high risk individuals showed a curve with a limited linear portion at high cell concentration, indicating that different mechanisms regulate the autoreactive response in the two groups studied. A follow-up study performed in three high risk and three normal individuals revealed a time-dependent increase of peripheral autoreactive T cells only in high risk subjects. Such increase correlates with the decrease of CD4+ cell number and CD4+/CD8+ cell ratio. Furthermore, the proliferative response of the same three subjects to gp160 peptides suggests a specific cellular reactivity to HIV components. This work has potential importance in understanding some of the early events in HIV infection.

Autoimmunity↗
PubMed1994

Serum reactivity against an immunoregulatory sequence of HIV p24 in HIV-1-infected subjects.

The aim of this study was to assess the antibody reactivity in HIV-infected subjects against an HIV-1 p24 sequence, p226 (aa226-237), including a seven amino acid epitope showing immunosuppressive activity in vitro and to evaluate the relationship between anti-peptide antibody levels and disease progression. Sera of HIV-infected subjects, at different stages of disease, were compared to control sera in a retrospective evaluation. Recombinant HIV-1 p24 and p24- and control-peptides were used in an enzyme immunoassay as targets for antibodies present in the sera. Antibodies directed against the whole p24 protein and its peptides were found in all the sera studied but at different levels. The anti-p226 reactivity was not significantly different at different clinical stages. Nevertheless, it was inversely correlated to the reactivity directed against the whole protein, that was lower in subjects characterized by low CD4 cell numbers.

Amino Acid Sequence↗
PubMed1993

T-cell and antibody response to Parietaria judaica allergenic fractions in atopic and nonatopic individuals.

The in vitro proliferative response to separated immunologically relevant components of Parietaria judaica pollen extract (PjE) was investigated by proliferation assay and limiting dilution analysis, in peripheral blood mononuclear cells from Parietaria-allergic subjects and nonallergic controls. In the same subjects, the profile of the antibody response to the PjE fractions was also studied by immunoblotting to evaluate the functional significance of allergen-induced T-cell activation in the two groups. The estimated frequency of PjE-reactive T cells in peripheral-blood mononuclear cells was low in both groups. No difference was found between the Parietaria-allergic subjects and nonallergic controls. To assess the overall contribution to the cellular response of PjE components of different molecular weights, we separated the extract by the SDS-PAGE technique, and the fractions were blotted onto nitrocellulose and solubilized. Almost all the 14 fractions tested induced T-cell proliferation, at different degrees of magnitude. Responses were similar in the allergic subjects and nonallergic controls. Immunoblotting demonstrated specific IgG antibodies to the 14 PjE fractions not only in the allergic subjects, but also in the healthy controls, whereas IgE antibodies were found, as expected, only in the sera from atopic subjects. These findings indicate that PjE fractions elicit similar T-cell activation and IgG production in allergic and normal subjects.

Cell Division↗
PubMed1992

The antigen-specific induction of normal human lymphocytes in vitro is down-regulated by a conserved HIV p24 epitope.

Synthetic peptides containing amino acid sequence 218-238 of the core protein p24 of human immunodeficiency virus type 1 (HIV-1) and progressively shorter sequences at its C-terminus, were tested for their effect on antigen dependent in vitro responses of peripheral blood lymphocytes (PBL) from normal human donors. A peptide as short as 7 amino acids, corresponding to a highly conserved sequence, was able to inhibit in a dose-dependent manner the induction of a specific primary antibody response to the sheep red cell (SRC) antigen, as well as the proliferative response to recall microbial antigens. The results of this study constitute additional evidence of the immunoinhibitory effects of HIV components and may help to unravel some of the pathogenic mechanisms of AIDS. Moreover, they are of potential relevance for the development of immunoprophylactic and therapeutic strategies.

Amino Acid Sequence↗
PubMed1992

Limiting dilution analysis of autoreactive T cells in patients affected by hydatid disease.

We evaluated the peripheral autoreactive response in patients with Echinococcus granulosus compared with healthy individuals. A limiting dilution analysis (LDA) was performed to estimate frequency of auto-reactive T cells and to detect the complex mechanism that often underlies the autoreactive response. Different LDA curves were seen in healthy controls and patients. The control group provided a straight line passing through the origin ('single hit' kinetics), indicating that only peripheral autoreactive T cells are limiting. On the other hand, autoreactive T cell titration in hydatid patients did not follow 'single hit' kinetics, suggesting that two or more cell types are titrated. More interestingly, we observed a very high frequency of autoreactive T cells in hydatid patients (1/1,000 to 1/2,500) compared with healthy controls (1/5,000 to 1/35,000). These data suggest that chronic infection may provide adequate stimuli for the induction of autoimmune disorders and increase in autoreactive T cells.

Autoimmunity↗