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C Agostini

Publications and source records attributed to C Agostini.

At least 37 records · Page 2Linked to original sources

Analysis of TNF-receptor and ligand superfamily molecules in patients with lymphoproliferative disease of granular lymphocytes.

In 21 patients with lymphoproliferative disease of granular lymphocytes (LDGL), we investigated the expression and the function of molecules belonging to TNF-receptor and TNF-ligand superfamilies (CD30/CD30L; CD40/CD40L; CD27/CD70; Fas [CD95]/FasL[CD95L]). Fourteen patients were characterized by a proliferation of granular lymphocytes (GLs) expressing the CD3(+)CD16(+) phenotype, whereas 7 cases showed the CD3(-)CD16(+) CD56 +/- phenotype. Our data show that both CD3(+) and CD3-GLs are preferentially equipped with CD30, CD40, CD40L, CD70, and CD95 antigens; this pattern is usually associated with the lack of CD27 and CD30L antigens expression. CD95L was demonstrated in the cytoplasm in 14 of 21 cases by flow cytometry, but a definite signal was demonstrated in all cases studied using polymerase chain reaction analysis. On functional grounds, a stimulatory activity on rIL-2 mediated redirected-cytotoxicity against Fcgamma+ P815 targets was demonstrated with anti-CD30, CD40, CD40L, CD70, CD95, and CD95L mAbs, although resting cells were unable to exhibit significant redirected-cell lysis. The addition of anti-CD30, CD30L, CD40, CD40L, CD95, and CD95L mAbs did not show any significant effect on cell proliferation at resting conditions or after rIL-2 stimulation, whereas anti-CD70 mAb mediated cell proliferation in 6 of 10 cases tested. This figure was not related to an increase in apoptotic cells, as investigated by Annexin-V expression. Our data indicate that both CD3(+) and CD3(-) GLs are equipped with different costimulatory antigens, supporting the concept that these cells are in vivo activated and suggesting that these molecules might play a role in the cytotoxic mechanisms of GLs. (Blood. 2000;96:647-654)

Adult↗

New pathogenetic insights into the sarcoid granuloma.

Although the most important enigma of sarcoidosis, ie, its etiology, remains an unsolved problem, the past few years have seen remarkable advances in understanding general immunologic and molecular aspects of the mechanisms leading to granuloma formation in sarcoidosis. It is now clear that during the sarcoid inflammatory process several cytokines are secreted at sites of disease activity; in addition, high affinity receptors for cytokines participating in the granuloma development have been recently identified. This article provides a detailed description of recent data that have clarified cellular interactions governing the dynamics of granuloma formation in sarcoidosis. Together, these new results provide important insights that can refocus efforts at developing immunotherapeutic methods of inhibiting cytokine production at sites of granuloma formation.

Apoptosis↗

CXC chemokines IP-10 and mig expression and direct migration of pulmonary CD8+/CXCR3+ T cells in the lungs of patients with HIV infection and T-cell alveolitis.

The recruitment of cytotoxic T lymphocytes (CTL) is considered to be the major tool for the clearance of HIV from the lower respiratory tract. In this study we evaluated the pathophysiologic role of two lymphotactic CXC chemokines (IP-10 and Mig) in the lung of HIV-infected patients. These chemokines stimulate the directional migration of activated T cells and interact with a specific receptor (CXC receptor 3, CXCR3). Lymphocytes recovered from the bronchoalveolar lavage (BAL) of HIV-infected patients with high intensity T-cell alveolitis were CD8+ T cells expressing high levels of CXCR3 and IFN-gamma, a phenotype that is characteristic of Tc1 cells. Pulmonary T cells expressing CXCR3 exhibited a high migratory capability in response to IP-10 and Mig. Alveolar macrophages recovered from patients with T-cell alveolitis bore the IFN-gamma-inducible proteins IP-10 and Mig. A positive correlation was demonstrated between IP-10, Mig, and IL-15 expression by alveolar macrophages. Interestingly, macrophages isolated from the lung of HIV-infected patients with T-cell alveolitis secreted definite levels of CXCR3 ligands capable of inducing T-cell chemotaxis. Taken together, our data suggest that chemotactic ligands that bind CXCR3 contribute significantly to the accumulation of HIV-specific CTL in the lung.

Adult↗

Expression of NADPH-diaphorase and colocalization with Fos in the brain neurons of the rat following visceral noxious stimulation.

We used double staining immunocytochemical techniques to determine whether nitric oxide (NO) and Fos immunoreactivity induced by noxious visceral stimulation were colocalized in the neurons of the supraspinal areas. We observed a considerable increase in Fos-positive neurons in many brain areas after noxious stimulation but only 15% of the Fos-positive neurons colocalized Nicotinamide Adenine Dinucleotide Phosphate Diaphorase (NADPH-d). The NADPH-d positive cells showed perikarya and cytoplasmic processes laying next to or more frequently apposed to Fos-positive neurons. This anatomical finding supported the hypothesis that also at supraspinal level NO is released near the neurons specifically activated and diffuses through the source cells to act on adjacent neurons playing a role in the central processing of pain transmission and modulation.

Animals↗

Antibodies to the IL-12 receptor beta 2 chain mark human Th1 but not Th2 cells in vitro and in vivo.

Great attention has been placed on the possibility of distinguishing Th1 from Th2 cells on the basis of differential expression of surface receptors. We have recently shown that the differential expression of the IL-12R beta 2 chain in Th1 and Th2 cells, as measured at the mRNA level, accounts for an important regulatory mechanism in the differentiation of the two cell subsets. In this study, we identify IL-12R expression at the protein level. We have generated an anti-IL-12R beta 2-specific mAb and analyzed IL-12R beta 2 expression on polarized Th cell populations generated in vitro and on T cells derived from patients with Th1- or Th2-mediated inflammatory conditions. Although IL-12R beta 2 was absent in freshly isolated PBMC and in cord blood cells, we were able to detect IL-12R beta 2 expression selectively in differentiated Th1 and T cytotoxic 1, but not Th2 or T cytotoxic 2 cells. In the presence of IL-12, cell surface expression of the IL-12R beta 2 subunit was readily detected on T cells after 24 h, reached the maximum at day 5, and declined thereafter. Most importantly, the anti-IL-12R beta 2 mAb recognizes lung T cells from patients with sarcoidosis, a disease characterized by a typical cell-mediated, Th1-type inflammatory response. In contrast, IL-12R beta 2 was absent in lung T cells from patients with allergic asthma, a disease characterized by a Th2-type inflammatory response. The mAb reported in this study should represent a powerful tool to investigate the role of Th1 and Th2 cells in inflammatory conditions and to monitor therapies aimed at altering the balance of Th cell subsets.

Adult↗

CD8 T-cell infiltration in extravascular tissues of patients with human immunodeficiency virus infection. Interleukin-15 upmodulates costimulatory pathways involved in the antigen-presenting cells-T-cell interaction.

Interleukin (IL)-15 regulates the proliferative activity of the CD8(+) T-cell pool in human immunodeficiency virus (HIV)-infected patients, thereby contributing to the maintenance of the CD8(+) T-cell-mediated immune response against HIV in extravascular tissues, including the lung. However, the effects of IL-15 on antigen-presenting cells (APC) during HIV infection are still unclear. In this study, we evaluated whether IL-15 regulates the macrophage stimulatory pathways governing inflammatory events that take place in the lung of patients with HIV infection. As a first step we evaluated the in vitro effects of IL-15 on lung macrophages retrieved from the respiratory tract of eight normal subjects. Although macrophages from uninfected individuals expressed the IL-15 binding proteins (IL-15Ralpha and the common gammac) at resting conditions, they did not express IL-15 messenger RNA (mRNA). However, a 24-hour stimulation with IL-15 induced the expression of interferon-gamma (IFN-gamma) and IL-15 itself, suggesting a role for this cytokine in the activation of the pulmonary macrophage pool during inflammation. As a confirmation of the role of IL-15 in this setting, at resting conditions, alveolar macrophages of patients with HIV infection and T-cell alveolitis expressed IL-15, IFN-gamma, and IL-15 binding proteins; showed an upmodulation of costimulatory molecules, B7 and CD72, which are involved in the APC of macrophages; and behaved as effective accessory cells because they elicited a strong proliferation of T cells. The accessory effect was inhibited by pretreatment with anti-CD72, anti-B7 (CD80 and CD86), and anti-IL-15 monoclonal antibodies (MoAb). We then investigated the relationship between IL-15 and the expression of costimulatory molecules by macrophages. A 24-hour stimulation of IL-15Ralpha+/gammac+ macrophages with IL-15 upregulated the expression of CD80 and CD86. The evidence that IL-15 upregulates the expression of coligands that favor the contact between T cells and APC, per se, triggers T-cell activation and proliferation and acts as a chemoattractant for T cells, suggests that IL-15 plays a key role in Tc1-mediated defense mechanisms taking place in extravascular tissues of patients with HIV disease.

Adult↗

The growth and the control of human immunodeficiency virus in the lung: implications for highly active antiretroviral therapy.

In recent years, it has become apparent that the lung is an important niche for the proliferation of human immunodeficiency virus (HIV), which may have implications for highly active antiretroviral therapy (HAART). The lung itself is a major site for the opportunistic infections associated with the progression to acquired immune deficiency syndrome (AIDS), specifically Pneumocystis carinii, Myobacterium tuberculosis and pyogenic bacteria. These cases of active pulmonary complications are direct indicators of enhanced progression to AIDS-defining illness and increased morbidity and mortality. It is therefore essential that the interaction between the lung and HIV is fully understood. Recent research indicates the lung may be a major sanctuary for the virus, with distinct evolution and replication in contrast to other target organs for HIV. In this review, we will discuss the recent findings of HIV infection, evolution, host factors involved in the control of HIV within the lung and the impact this may have on current therapy.

AIDS-Related Opportunistic Infections↗

Regulation of alveolar macrophage-T cell interactions during Th1-type sarcoid inflammatory process.

The accessory function of antigen-presenting cells depends on the presence of a number of costimulatory molecules, including members of the B7 family (CD80 and CD86) and the CD5 coligand CD72. The aim of this study was to evaluate the regulation of T cell-antigen-presenting cell costimulatory pathways in the lung of patients with a typical Th1-type reaction, i.e., sarcoidosis. Although normal alveolar macrophages (AMs) did not bear or bore low levels of costimulatory molecules, AMs from sarcoid patients with CD4 T-cell alveolitis upmodulated CD80, CD86, and CD72 and expressed high levels of interleukin (IL)-15; lymphocytes accounting for T-cell alveolitis expressed Th1-type cytokines [interferon (IFN)-gamma and/or IL-2] and bore high levels of CD5 and CD28 but not of CD152 molecules. In vitro stimulation of AMs with Th1-related cytokines (IL-15 and IFN-gamma) upregulated the expression of CD80 and CD86 molecules. However, stimulation with IL-15 induced the expression of Th1-type cytokines (IFN-gamma) and CD28 on sarcoid T cells, suggesting a role for this macrophage-derived cytokine in the activation of the sarcoid T-cell pool. The hypothesis that CD80 and CD86 molecules regulate the sarcoid T-cell response was confirmed by the evidence that AMs induced a strong proliferation of T cells that was inhibited by pretreatment with CD80 and CD86 monoclonal antibodies. To account for these data, it is proposed that locally released cytokines provide AMs with accessory properties that contribute to the development of sarcoid T-cell alveolitis.

Adult↗

The chemokine receptor CXCR3 is expressed on malignant B cells and mediates chemotaxis.

B- and T-cell recirculation is crucial for the function of the immune system, with the control of cell migration being mainly mediated by several chemokines and their receptors. In this study, we investigated the expression and function of CXCR3 on normal and malignant B cells from 65 patients with chronic lymphoproliferative disorders (CLDs). Although CXCR3 is lacking on CD5(+) and CD5(-) B cells from healthy subjects, it is expressed on leukemic B lymphocytes from all (31/31) patients with chronic lymphocytic leukemia (CLL). The presence of CXCR3 was heterogeneous in other B-cell disorders, being expressed in 2 of 7 patients with mantle cell lymphoma (MCL), 4 of 12 patients with hairy cell leukemia (HCL), and 11 of 15 patients with other subtypes of non-Hodgkin's lymphomas (NHLs). Chemotaxis assay shows that normal B cells from healthy subjects do not migrate in response to IFN-inducible protein 10 (IP-10) and IFN-gamma-induced monokine (Mig). In contrast, a definite migration in response to IP-10 and Mig has been observed in all malignant B cells from patients with CLL, but not in patients with HCL or MCL (1/7 cases tested). Neoplastic B cells from other NHLs showed a heterogenous pattern. The migration elicited by IP-10 and Mig was inhibited by blocking CXCR3. No effect of IP-10 and Mig chemokines was observed on the cytosolic calcium concentration in malignant B cells. The data reported here demonstrate that CXCR3 is expressed on malignant B cells from CLDs, particularly in patients with CLL, and represents a fully functional receptor involved in chemotaxis of malignant B lymphocytes.

Adult↗

[Physiologic role of the somatotrophic GH-IGF and others hormones in the domestic animals growth. Influence of the nutritional status].

In this review main hormones involved in development and muscle growth are shown with special emphasis on growth hormone (GH) and insulin-like growth factors (IGF). Chemist composition, synthesis place, action way and main action mechanisms of these hormones are reviewed. Nutritional factors which modified seric metabolites, and their effects on hormone secretion are detailed. It was observed that GH, IGF, thyroid hormones, insulin, glucocorticoids and sexual steroids act in a complex and cordinated way to produce a productive response to different> nutritional strategies.

Animals↗

Involvement of the IP-10 chemokine in sarcoid granulomatous reactions.

The accumulation of T cells and monocytes at sites of ongoing inflammation represents the earliest step in the series of events that lead to granuloma formation in sarcoidosis. In this study, we evaluated the pulmonary production of IFN-inducible protein 10 (IP-10), a CXC chemokine that stimulates the directional migration of activated T cells. Striking levels of IP-10 were demonstrated in the bronchoalveolar lavage (BAL) fluid of 24 patients with pulmonary sarcoidosis and lymphocytic alveolitis, as compared with patients with inactive disease or control subjects. A positive correlation was demonstrated between IP-10 levels and the number of sarcoid CD45R0+/CD4+ cells in the BAL. Immunochemistry, performed with an anti-human IP-10 polyclonal Ab in lymph nodes displaying prominent sarcoid granulomas, showed that cells bearing IP-10 were mainly epithelioid cells and CD68+ macrophages located inside granulomatous areas. Macrophages recovered from the BAL of sarcoid patients stained positive for IP-10 protein. Furthermore, alveolar macrophages isolated from sarcoid patients with T cell alveolitis and cultured for 24 h in presence of IFN-gamma secreted definite levels of IP-10 capable of inducing T cell chemiotaxis. Interestingly, alveolar lymphocytes recovered from patients with active sarcoidosis were CD4+ T cells expressing Th1 cytokines (IL-2 and IFN-gamma) and high levels of CXCR3. Taken together, these data suggest the potential role of IP-10 in regulating the migration and activation of T cells toward sites of sarcoid inflammatory process and the consequent granuloma formation.

Adult↗

Induction of NADPH-diaphorase activity in the rat periaqueductal gray matter after nociceptive visceral stimulation.

Nitric oxide (NO) is a neuronal messenger that it is thought to be involved in the nociceptive transmission modulation. The activity of nicotinamide adenine dinucleotide phosphate diaphorase (NADPH-d) was shown to be identical to NOS activity in the brain. Since the periaqueductal gray matter (PAG) plays an important role in pain perception and antinociception this study was carried out to monitor the expression of NADPH-d in PAG after nociceptive visceral stimulation. Our data showed that the noxious visceral stimulation significantly increased NADPH-d positive neurons and that these neurons were localized in the ventrolateral areas of the PAG. These findings suggest that NO in the PAG may play a role in pain modulation and antinociception.

Acetic Acid↗

Impaired cytokine production by neutrophils isolated from patients with AIDS.

OBJECTIVES: To determine the ability of neutrophils isolated from HIV-seropositive patients to produce proinflammatory cytokines. DESIGN: The in vitro responsiveness of polymorphonuclear neutrophils (PMN) and peripheral blood mononuclear cells (PBMC) to lipopolysaccharide (LPS), used in the presence or absence of interferon (IFN)gamma, was determined in 47 HIV-positive patients with advanced stages of virus infection. METHODS: Cytokines in cell-free supernatants were measured by enzyme-linked immunosorbent assay or radioimmunoassay. RESULTS: Cell-free supernatants from PMN isolated from the peripheral blood of HIV-positive patients and stimulated with LPS contained increased amounts of tumour necrosis factor (TNF)-alpha and interleukin (IL)-8 with respect to supernatants obtained from PMN of normal donors. In contrast, release of IL-1beta and IL-1ra (IL-1 receptor antagonist) in response to LPS, or LPS plus IFNgamma, was found to be lower in PMN from HIV-positive patients than in PMN from controls, but was significant only in the case of IL-1ra. Furthermore, the release of IL-12 induced by LPS or LPS plus IFNgamma did not significantly differ between PMN from HIV-positive patients and healthy donors. Concerning PBMC, the production of TNF-alpha and IL-12 in response to LPS, or LPS plus IFNgamma, was found to be significantly higher in cells isolated from HIV-positive patients, whereas the release of IL-1beta was significantly lower. In the case of IL-8, no statistically significant difference was found between PBMC isolated from HIV-positive patients and healthy donors. CONCLUSIONS: Collectively, the data suggest that in HIV-positive patients with advanced stages of disease, the ability of PMN to produce specific cytokines in response to LPS is significantly altered. Alterations in this ability might contribute to the evolution of HIV disease.

Adolescent↗

HIV load in highly purified CD8+ T cells retrieved from pulmonary and blood compartments.

The pulmonary microenvironment can be HIV infected from the asymptomatic period of HIV infection and it has been demonstrated that HIV presence elicits a discrete virus-specific CTL immune response in the lungs. In this study we analyzed T cell subsets and compared the proportion of CD8+ T cells harboring HIV in the lung and in the circulation of HIV-seropositive patients with T cell alveolitis. Proviral load was assessed using the DNA-polymerase chain reaction technique on highly purified CD8+ T cells isolated from peripheral blood and bronchoalveolar lavage. The proviral load of pulmonary CD8+ T cells showed an upward trend with respect to corresponding samples isolated from the peripheral blood of the same patients.

Adult↗