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Biomedical subjects

L Trentin

Publications and source records attributed to L Trentin.

At least 109 records · Page 6Linked to original sources
PubMed1989

Lymphoproliferative disease of granular lymphocytes in a patient with concomitant hepatitis B virus infection of CD4 lymphocytes.

In this report we studied a 35-year-old male who developed an abnormal expansion of granular lymphocytes (GL) which spontaneously regressed over a period of 2 years. The immunological and molecular characterizations of expanded cells showed the CD3+,CD8+,HNK-1+ phenotype, a polyclonal organization of the T-cell receptor beta-chain gene and normal natural killer activity. At the time of presentation, spot and blot hybridization techniques revealed the presence of viral hepatitis B virus (HBV) DNA sequences only in highly enriched CD4+ T cells, while proliferating GL were negative. With this as a background, we addressed the question of whether in our case the polyclonal GL proliferation represented an immunoreactive response against CD4+ infected cells. In particular, we tested the possibility that expanded GL could be cytotoxic against autologous infected CD4+ cells. At the time of the first determination, when several of the CD4+ cells harbored HBV, GL showed a minimal degree of cytotoxicity against 51Cr-labeled CD4+ cells; 2 years later, when GL became capable of lysing these targets, the appearance of the specific cytotoxicity was concomitant with the disappearance of the HBV-infected CD4+ cells and with the recovery of granular lymphocytosis. Taken together, our data suggest that in this case GL proliferation could represent an immunoreactive process against CD4+ cells.

Adult↗
PubMed1989

Hairy cell sensitivity to the lysis in vitro. Role of the anti-CD3 antibody in generating a susceptibility to the lysis.

Experiments herein reported were designed to clarify the degree of sensitivity of hairy cells to lysis in vitro. The cytotoxic capacity of peripheral blood lymphocytes from hairy cell leukemia patients against autologous and/or allogenic hairy cells was tested both at resting conditions and after in vitro stimulation. While effectors activated by interferon alpha, lectins, or interleukin-2 were unable to induce a lysis of hairy cells, in some cases we were successful in eliciting a definite lysis of these cells by triggering the effector cells with anti-CD3 monoclonal antibodies. Our results favour the interpretation that hairy cells are relatively, but not completely resistant to in vitro lysis. Furthermore, the evidence that anti-CD3 antibodies increase the efficacy of the cytotoxic machinery might support the use of these molecules in designing new immunotherapeutic approaches against tumor targets.

Aged↗
PubMed1989

Increased levels of soluble CD8 molecule in the serum of patients with acquired immunodeficiency syndrome (AIDS) and AIDS-related disorders.

In this study we investigated the serological levels of the soluble form of the CD8 molecule (s-CD8) in 97 human immunodeficiency virus (HIV) seropositive patients. The control groups included 20 normal heterosexual subjects and 19 healthy seronegative subjects belonging to risk groups for AIDS. Our results show that patients with HIV infection have significantly higher levels of s-CD8 U/ml than the control groups. When the patients were further subdivided according to the Centers for Disease Control (CDC) classification, s-CD8 U/ml values were consistently increased in all HIV patients, irrespective of the CDC stages. No statistically significant correlation was found between the serological levels of s-CD8/ml and the absolute numbers of CD8 lymphocytes/mm3, in both HIV seropositive patients and control groups. Since in the more advanced stages of HIV infection (IV-A, IV-C1) the decrease in the absolute number of CD8+ cells was not followed by a decrease in s-CD8 levels, it is conceivable that an increased release and/or shedding of s-CD8 per cell might occur in these patients. In fact, when the results were expressed as s-CD8 units per CD8 positive cell (s-CD8/absolute number of CD8), the levels of s-CD8/cell were higher in patients belonging to the IV-A and IV-C1 CDC groups (1.94 U/cell +/- 0.33 and 3.39 U/cell +/- 0.5, respectively) compared to normal controls (P less than 0.001), HIV seronegative subjects at risk for AIDS (P less than 0.001), and the other patients' groups (II and III CDC groups, respectively, P less than 0.001 and P less than 0.001). The evidence herein provided that in patients with HIV infection s-CD8 levels are increased suggests a possible pathogenetic role of the cells involved in the release of this molecule.

AIDS-Related Complex↗
PubMed1989

Release of natural killer cytotoxic factor in patients with lymphoproliferative disease of granular lymphocytes.

To further investigate the mechanisms accounting for defective natural killer (NK) activity observed in the majority of patients with lymphoproliferative disease of granular lymphocytes (LDGL), we have studied the generation of natural killer cytotoxic factor (NKCF) from peripheral blood lymphocytes recovered from twelve LDGL patients. On the basis of their cytotoxic activity against the K-562 target cells, cases under study were separated in two groups. Cells from five patients, referred to as NK+, were found to exhibit high levels of NK-cell mediated cytotoxicity; cells from seven patients, referred to as NK-, despite their ability to bind to the K-562 targets, displayed a defective NK function. The coculture of cells from NK+ patients with NK sensitive K-562 cells triggered a significantly higher production of NKCF with respect to NK- patients (p less than 0.001 at 1:2 dilution). Using phytohemagglutinin (PHA) as the NKCF stimulator, differences between the groups were not significant, due to a recovery of NKCF generation in NK- patients. Furthermore, a consistent lectin (PHA) dependent cellular cytotoxicity (LDCC) was exhibited by both groups of patients. The addition of gamma-interferon (IFN-gamma) or interleukin-2 (IL-2) during NKCF generation did not significantly modify the production of this factor. Our data point out that (a) NKCF is involved in the lytic activity of LDGL patients' cells, (b) a constitutional impairment in the generation of NKCF is not present in NK- patients, since recovery of lytic function occurs after PHA stimulation, and (c) IL-2 and IFN-gamma do not play a relevant role in triggering NKCF production when added during the generation of this factor. These studies help to clarify the factors involved in the cytotoxic machinery of LDGL patients' cells, suggesting that the defect of the cytotoxic function observed in some LDGL patients could lie at the level of target recognition.

Adult↗
PubMed1989

Serum levels of soluble CD8 are increased in patients with B chronic lymphocytic leukemia.

Serum levels of the soluble form of the CD8 (s-CD8) antigen were evaluated in the peripheral blood of 44 patients with B-CLL, using an enzyme-linked immunosorbent assay, and were correlated with clinical features and relevant hematological and immunological data. Increased values were observed with respect to normal age-matched controls (mean +/- S.E.M. 603 U/ml +/- 81 vs. 315 U/ml +/- 31, respectively; P less than 0.0001). This increase was observed in all stages of the disease, excluding stage 0 (mean 277 U/ml +/- 45). A general trend pointing to lower values overall in patients with less invasive disease was observed. In fact, the rank correlation test showed that the serum levels of s-CD8 correlate significantly with the WBC counts, the CD4/CD8 ratio, and also with the levels of serum immunoglobulins. On the contrary, no correlation was observed between s-CD8 levels and the absolute number of circulating CD8+ cells in individual cases. Therefore, the increase of s-CD8 is unlikely to be a mere expression of the increase of the CD8 cell number, but seems related to an increase of the activation phenomena involving the CD8+ T cell subset.

Antigens, Differentiation, T-Lymphocyte↗
PubMed1989

Serum levels of soluble interleukin-2 receptor in hairy cell leukaemia: a reliable marker of neoplastic bulk.

In hairy cell leukaemia (HCL), the strong membrane expression of the Tac antigen, corresponding to the p55 chain of the interleukin-2 receptor (IL-2R), is associated with the presence in the serum of high levels of a soluble form of the same molecule (sIL-2R). Previous observations that therapy-induced clinical and haematologic improvement in HCL is accompanied by a progressive decrease of sIL-2R suggest a possible correlation between sIL-2R levels and tumour burden. To verify this hypothesis, we monitored the variation of sIL-2R values in 13 non-splenectomized HCL patients admitted for treatment with recombinant interferon alpha-2. The data were correlated with the estimated weight of bone marrow (BM) and spleen infiltration, which in these patients almost entirely account for the tumour mass. The regression analysis test showed a direct correlation between sIL-2R values and both BM neoplastic involvement (r = 0.63) and spleen tumour mass (r = 0.76). In addition, the correlation was further improved (r = 0.86) when sIL-2R values were correlated with the total neoplastic mass, as calculated by the sum of spleen and BM neoplastic tissue weight. These data indicate that the detection of sIL-2R in HCL is a reliable non-invasive marker of tumour burden, which can be regarded as an additional useful tool for monitoring treatment response.

Adult↗
PubMed1989

Pulmonary alveolar macrophages from patients with active sarcoidosis express type IV collagenolytic proteinase. An enzymatic mechanism for influx of mononuclear phagocytes at sites of disease activity.

Alveolar macrophages (AMs) recovered from the bronchoalveolar lavage (BAL) of 44 patients with sarcoidosis were evaluated for their ability to release type IV collagenolytic metalloproteinase (IV-Case). This enzyme, which is produced by peripheral blood monocytes (PBMs) but not by tissue macrophages, degrades type IV collagen, the major structural component of vessel wall basement membranes, and helps to promote the migration of PBMs from the blood compartment to peripheral tissues. Our results demonstrated that AMs from patients with active sarcoidosis released significantly increased levels of IV-Case with respect to patients with inactive disease and control subjects. After in vitro culture, sarcoid AMs secreted IV-Case during the first 24 h of collection; after that time, AMs progressively lost their ability to release IV-Case. Exposition of both sarcoid and normal AMs to recombinant IL 2 or gamma IFN did not influence their property to release IV-Case. The immunoblot analysis of IV-Case demonstrated complete identity between IV-Case released by AMs and the degradative enzyme obtained from PBMs. The increased property to release IV-Case was significantly related to the increase of the absolute number of AMs and, in particular, of AMs bearing two determinants that are usually expressed by most PBMs (CD11b and CD14). Selective depletion of CD11b+/CD14+ AMs from the entire macrophagic population was associated with the recovery of the IV-Case activity to normal values. A positive correlation was also found between the increase in the absolute number of lung T cells and the enhanced CD4/CD8 pulmonary ratio. A 6-mo follow-up study indicated a significant association between the positivity for the 67Gallium scan and the increased property of AMs to release IV-Case. Our data are consistent with the hypothesis that a IV-Case mediated influx of peripheral monocytes takes place in the lung of sarcoid patients. Furthermore, the correlation found between the IV-Case release and disease activity suggests that this assay could represent a useful tool in sarcoidosis disease staging.

Adult↗
PubMed1989

Generation of superoxide anion by alveolar macrophages in sarcoidosis: evidence for the activation of the oxygen metabolism in patients with high-intensity alveolitis.

We studied superoxide anion (O2) generation by alveolar macrophages (AM) isolated from bronchoalveolar lavages (BAL) of patients with sarcoidosis, and assayed immediately after the isolation or after maintenance in culture for 2 days. In assays of cells freshly isolated from BAL, AM of patients with active sarcoidosis with a high-intensity lymphocytic alveolitis produced more O2- in response to phorbol myristate acetate than AM of patients with inactive sarcoidosis. Also, after 2 days of cultivation sarcoid AM were heterogeneous in their capability to metabolize oxygen, although both AM of active and inactive sarcoid patients produced higher amounts of O2- than AM of healthy subjects. In vitro treatment with recombinant interferon-gamma (rIFN-gamma) caused an enhancement of the capability of AM of inactive sarcoid patients to produce O2- in response to PMA. AM of patients with active sarcoidosis did not respond to rIFN-gamma when they already produced O2- vigorously. However, they became sensitive to the activating effect of rIFN-gamma after the down-modulation of their capability to produce O2-, that occurred upon prolonged cultivation. Monocytes isolated from blood of sarcoid patients and assayed immediately or after different times of cultivation did not produce more O2- than control monocytes and monocyte-derived macrophages, thus indicating that the activation of AM in sarcoidosis is likely a local phenomenon. These studies strengthen the notion that T lymphocyte-macrophage interaction is a critical event in the pathogenesis of sarcoidosis and establish that the enhanced capability to metabolize oxygen to highly reactive intermediates by AM is one of the consequence of this interaction.

Adult↗
PubMed1988

Increased serum levels of soluble interleukin-2 receptor in patients with systemic lupus erythematosus and rheumatoid arthritis.

In this study we investigated the serum levels of a released soluble form of the interleukin-2 receptor (sIL-2R) in 42 patients with rheumatoid arthritis and in 12 cases of systemic lupus erythematosus. Data were evaluated in relationship to the clinical phase and compared with those observed in normal controls (N = 56) and in osteoarthritis (N = 7). Increased levels were observed in both rheumatoid arthritis (mean +/- SE, 604 +/- 49 U/ml) and systemic lupus erythematosus (1438 +/- 481 U/ml). These values were significantly higher than in control (256 +/- 15 U/ml; P less than 0.001) and in osteoarthritis (298 +/- 33 U/ml; P less than 0.001) groups. In addition, the highest values were associated with the active phases of both rheumatoid arthritis (active vs inactive, 771 +/- 78 vs 451 +/- 39 U/ml; P less than 0.001) and systemic lupus erythematosus (active vs inactive, 2108 +/- 489 vs 499 +/- 75 U/ml; P less than 0.001). Our findings suggest that the detection of sIL-2R in rheumatoid arthritis and in systemic lupus erythematosus may represent a good marker of disease activity, which indirectly indicates the ongoing activation and/or proliferation of immunoreactive cells which are involved in the pathogenetic events of these autoimmune conditions.

Acute Disease↗
PubMed1988

Longitudinal study of alveolitis in hypersensitivity pneumonitis patients: an immunologic evaluation.

Cells recovered from bronchoalveolar lavage were studied, both from a phenotypic and functional point of view, in 18 patients with hypersensitivity pneumonitis (HP) during a prolonged follow-up. A series of monoclonal antibodies against different lymphocyte subpopulations, including T cells, T cell subsets, and natural killer (NK) cells have been used. In some cases, an immunohistologic analysis of lung tissue sections has also been performed. The NK activity has been evaluated with regard to the in vitro function. At the time of the first evaluation, a high number of CD8+ cells with an imbalance of CD4/CD8 ratio had been demonstrated in patients with HP. Consecutive bronchoalveolar lavage evaluations demonstrated a persistent increase of CD8+ cells and a reversal of CD4/CD8 ratio in patients who continued to be regularly exposed to etiologic antigens at work (W+). In the same cases, a persistent increase of NK cells was demonstrated. Cytotoxic cells demonstrated a persistently enhanced in vitro lytic function during the follow-up, even though there appeared to be a trend toward the normal range. Patients who continued to live in agricultural environments but were not further exposed to specific antigens at work (W-) exhibited a recovery of CD4+ cells, a decrease in CD8+ cells, and an increase of CD4/CD8 ratio to the normal range 6 months after the first observation. Immunohistologic analysis, performed at the time of the first evaluation, demonstrated a diffuse infiltration of lung parenchyma by CD8+ cells, both in W+ and W- patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Alveolitis, Extrinsic Allergic↗
PubMed1988

Natural killer cell function and lymphoid subpopulations in acute non-lymphoblastic leukaemia in complete remission.

A long term follow-up study has been undertaken in 33 patients with acute non-lymphoblastic leukaemia (ANLL) in order to establish whether a correlation exists between the clinical course and the immunologic pattern of lymphoid subpopulations. Peripheral blood lymphoid cells have been investigated longitudinally (each 1 to 4 months) during complete remission (CR), by morphologic, phenotypic and functional analyses. Particular attention has been paid to the evaluation of the natural killer (NK) cell compartment, by the detection of cells expressing an NK-related phenotype and by NK in vitro assay. Among the patients so far evaluable, 20 relapsed (R) and 10 are long survivors in CR 'off therapy' (LS). The most relevant finding was represented by statistically higher values of NK activity observed in LS vs. R patients (P less than 0.01). The removal of adherent cells before the NK assay, performed to investigate the possible inhibitory effect on NK function played by the macrophage component, abolished this difference, due to a selective increase of NK function in the R group. The longitudinal study revealed that NK activity tended to decrease in individual patients who subsequently relapsed. These data suggest a possible role of NK cells in the relapse control of ANLL, although it cannot be excluded that the low level of NK activity observed in the R group is the result of impending relapse rather than its cause.

Adolescent↗
PubMed1988

Different types of cytotoxic lymphocytes recovered from the lungs of patients with hypersensitivity pneumonitis.

To better characterize the cytotoxic lymphocytes present in the lung of patients with hypersensitivity pneumonitis (HP), we studied cells recovered from bronchoalveolar lavage (BAL) of 5 subjects with farmer's lung disease. Specifically, this cytotoxic activity was evaluated: (1) in resting conditions and after boosting with interleukin-2 (IL-2) against NK-sensitive, NK-insensitive target cell lines, and against specific antigen-sensitized (Micropolyspora faenl) autologous monocytes; (2) after removal of NK-related populations; (3) in blocking experiments with CD3 and CD2 monoclonal antibodies. It has been demonstrated that lung lymphocytes from patients with HP in resting conditions are able to lyse both NK-susceptible and NK-resistant targets and that IL-2 is able to induce BAL cells to generate lymphokine-activated killer (LAK) cell activity. Neither resting nor activated HP lung lymphocytes were capable of specific lysis of autologous monocytes previously sensitized with specific antigen. Removal of HNK-1+ or CD16+ cells reduces, but does not completely eliminate the cytotoxic function, whereas blocking with anti-CD3 monoclonal antibody almost completely abolishes the cytotoxicity. All these data taken together suggest that different types of cytotoxic cells are recovered from the BAL of patients with HP, i.e., NK cells and non-MHC-restricted cytotoxic lymphocytes, including LAK cells.

Adult↗
PubMed1988

Phenotypical and functional analysis of bronchoalveolar lavage lymphocytes in patients with HIV infection.

The lungs of patients with acquired immunodeficiency syndrome (AIDS) are frequently affected by opportunistic and nonopportunistic infections and pulmonary localizations of Kaposi's sarcoma. The aim of this study was to verify whether, in patients with human immunodeficiency virus (HIV) infections, immunologic pulmonary abnormalities set the stage for the lung complications. For this purpose, a phenotypic and functional characterization of lymphocytes recovered from the bronchoalveolar lavage (BAL) fluid of 24 patients with clinical symptoms and signs of HIV infections was performed (six patients with constitutional disease, five patients with neurologic manifestations, and 13 patients with full-blown AIDS). Our data showed that (1) in patients with HIV, the percentage and absolute number of pulmonary CD8 cells were significantly increased over those in control subjects (in 25% of these patients, mostly with full-blown AIDS, CD8 cells sustained an alveolitis); (2) lung CD4 cells were reduced in percentage but not in absolute number, with the exception of patients with AIDS in whom a significant decrease of the absolute number of BAL CD4 cells has been found (further phenotypic analysis of CD4 lymphocytes showed a reduction of the expression of T4A, B, and E with respect to the T4, T4C, T4D, and T4F epitopes); (3) although the number of BAL cells bearing NK-related determinants was increased, we were unable to demonstrate any in vitro natural killer cell activity. We suggest that the impairment of a proper NK activity in the lungs of these patients might be central to the mechanisms leading to the in situ immunodeficiency state and to the pulmonary complications characterizing AIDS.

Acquired Immunodeficiency Syndrome↗
PubMed1988

Origin of the soluble interleukin-2 receptor in the serum of patients with hairy cell leukemia.

High levels of soluble IL-2 receptor (sIL-2R) are detectable in the serum of HCL patients. To determine the cell source of this molecule, we evaluated the presence of sIL-2R in the supernatants obtained from in vitro cultures of leukemic (hairy cell, HC) and non-leukemic lymphocytes from six untreated HCL patients and from an additional four patients under therapy with rIFN-alpha 2. We demonstrated that cultured HCs at resting conditions were able to spontaneously release the sIL-2R, whereas control enriched B cells did not. This phenomenon was present only when culturing HCs recovered from patients observed at the time of diagnosis but was not observed during treatment with rIFN-alpha 2. Following activation in vitro with a series of different stimulatory agents including BCGF, phorbol myristate acetate, and anti-human IgM antibody, cultured HCs increased their capability to shed the IL-2R molecules. On the other hand, the release of sIL-2R from enriched T cell populations from HCL patients did not significantly differ from the value obtained in controls. Taken together, these findings provide evidence that leukemic B cells represent the main source of sIL-2R in HCL patients and further emphasize the importance of evaluating this parameter as a relevant marker for monitoring the effectiveness of rIFN-alpha 2 therapy.

Adult↗
PubMed1988

Immunohistochemical analysis of sarcoid granulomas. Evaluation of Ki67+ and interleukin-1+ cells.

Proliferating cells have been immunophenotypically characterized in lymph node and bronchoalveolar lavage (BAL) samples obtained from patients with active and inactive sarcoidosis with the cell-cycle-related antigen Ki67. Ki67 monoclonal antibody was used by combined immunohistochemical methods together with antibodies recognizing macrophage- and T-cell-subset-related antigens using avidin-biotin peroxidase (ABC) and alkaline phosphatase-anti-alkaline phosphatase (APAAP) systems. Many proliferating Ki67+ cells were found in affected mediastinal lymph nodes. These cells were mainly located around granulomas and exhibited phenotypical markers of helper/inducer T cells (CD3+, CD4+). Ki67+ macrophages could not be detected in the same lesions with this technique. A different picture was found in BAL preparations where proportions of both T lymphocytes and macrophages were Ki67+. The presence of replicating lymphocytes could be correlated to disease activity, whereas the proportions of Ki67+ macrophages did not show significant differences between active and inactive disease. Interleukin-1 (IL-1) expression was investigated in the same samples with a specific antiserum. Epithelioid macrophages in granulomas and BAL macrophages in all cases exhibited cytoplasmic staining revealing an activated status. Interestingly, giant cells in granulomas were mainly devoid of IL-1 immunoreactivity. These studies support the concept that activated cells at different sites of ongoing inflammation play a central role in the mechanisms accounting for granuloma formation.

Adult↗
PubMed1987

The lymphoproliferative disease of granular lymphocytes. A heterogeneous disorder ranging from indolent to aggressive conditions.

A multiparameter analysis, which included the evaluation of clinical features, cell morphology, karyotype, phenotypic and functional immunologic findings, and T-cell receptor beta-chain configuration was performed on 34 patients with lymphoproliferative disease of granular lymphocytes (LDGL). The two-fold aim of the study was to identify the most useful tools that would more accurately characterize these patients and to deal with the problem of classifying these lymphoproliferative disorders. The data presented in this article suggest that a single parameter may not be sufficient to define the nature of the proliferating cells or to predict the clinical course of the disease and prognosis for the patient. The use of a multiparameter approach, however, may reach this goal, thus providing important prognostic and therapeutic information. Our study supports the concept that lymphoproliferative disease of granular lymphocytes is a heterogeneous disorder that ranges from indolent and possibly reactive conditions to the manifestation of aggressive malignancies.

Adult↗
PubMed1987

Immunologic abnormalities in angioimmunoblastic lymphadenopathy.

In this study we describe the results of phenotypic, serologic, and functional analyses performed in nine patients with angioimmunoblastic lymphadenopathy (AILD). The study investigates the nature of the T-cell defects which seem to represent a consistent feature in this disease. The study, based on the analysis of T-cell subsets with monoclonal antibodies and on functional in vitro tests, showed the following main abnormalities: reduction of the absolute number of circulating T-cells; inversion of the CD4/CD8 ratio, both in the peripheral blood and in the involved lymph nodes; high percentages of activated T-cells (CD8+/HLA-DR+); defective T-cell response in vitro to the PHA mitogen; and minimal helper and enhanced in vitro suppressor functions. Some of these immunologic dysfunctions are also observed in acquired immune deficiency syndrome (AIDS) which has in common with AILD several clinical features. However, no evidence of HTLV-III infection could be demonstrated in our patients with AILD.

Acquired Immunodeficiency Syndrome↗