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A Stoppacciaro

Publications and source records attributed to A Stoppacciaro.

86 records · Page 5Linked to original sources
PubMed1989

Immunoreactivity for IL-1 beta and TNF alpha in human lymphoid and nonlymphoid tissues.

Monoclonal antibodies (MAbs) against two non-cross-reacting antigens of human IL-1 beta (Vhp20 and BRhC3) and human TNF alpha (B154.2 and B154.7) were applied to identify cytokine-containing cells in tissue sections and in cell suspensions. IL-1 beta- or TNF alpha-positive cells were not present in immunostained cytocentrifuge smears prepared from freshly isolated peripheral blood leukocytes, spleen, and lymph node cells. After 18 hours of culture with bacterial endotoxin (LPS), 80% to 90% of blood monocytes, 30% of spleen macrophages, and 2% to 28% of lymph node macrophages were strongly positive for IL-1 beta with either of the MAbs. Furthermore, 25% to 35% of blood monocytes and 6% to 60% of lymph node macrophages were stained for TNF alpha. Cells positive for IL-1 beta or TNF alpha were extremely rare in sections of normal thymus, spleen, and lymph nodes. Immunoreactivity for IL-1 beta or TNF alpha was frequently observed in sections of granulomatous lymphadenitis (N = 11). IL-1 beta or TNF alpha staining was confined to the epithelioid macrophages forming the granuloma, and the intensity of TNF alpha reactivity was generally stronger. The high frequency of cytokine-containing cells in this pathologic condition was confirmed in a cell suspension study showing that 20% of epithelioid macrophages were weakly positive for IL-1 beta and 80% were strongly positive for TNF alpha. The presence of cytokine-containing cells was investigated in cryostat sections of several nonlymphoid organs with normal histologic appearance. IL-1 beta reactivity was not observed in any of the tissues. TNF alpha reactivity was frequently demonstrated in isolated macrophages embedded in the interstitial connective tissue.

Humans↗
PubMed1988

Limiting dilution analysis of TNF producing cells in C3H/HeJ mice.

A limiting dilution assay (LDA) that measures the frequency of TNF producing cells is described. LDA determination is based on the inhibition of growth of a highly TNF sensitive subline from the WEHI-164 fibrosarcoma by using a micro assay sensitive to single picogram amounts of recombinant murine TNF. Using such LDA, it was determined that the reported deficiency in LPS-induced TNF production in C3H/HeJ mice is a function of reduced frequency of TNF producing cells rather than a complete lack of responsiveness. In bulk culture, LPS-triggered TNF was produced by Thy-1.2 negative spleen cells with activity recovered in both G10 Sephadex adherent and nonadherent subpopulations. LPS stimulation of spleen cells from C3H/HeJ mice resulted in TNF mRNA expression as shown in both Northern blots and in situ hybridization. The frequency of TNF mRNA bearing cells in control of C3H/HeSnJ mice by in situ hybridization correlated with that found for TNF producing cells in LDA. In C3H/HeJ spleen, significantly higher numbers of TNF mRNA positive cells were found than were shown to produce TNF in LDA.

Animals↗
PubMed1988

Human natural cytotoxic activity mediated by tumor necrosis factor: regulation by interleukin-2.

Freshly obtained normal lymphoid cells kill certain tumor target cells in vitro. Using peripheral blood lymphocytes (PBLs) and the human tumor target cell line BT-20, we have defined a tumor necrosis factor (TNF)-dependent, cell-mediated cytotoxic mechanism that is homologous to the murine natural cytotoxic (NC) cell activity. Human NC cell activity was detected in freshly isolated PBLs and was augmented by short in vitro pulses with recombinant human interleukin-2 but not with recombinant human alfa interferon. Monoclonal anti-TNF antibodies inhibited the killing of the target cells. The independence of interferon and the mediation of killing by TNF distinguish human NC cell activity from natural killer and lymphokine-activated killer cell activities.

Cells, Cultured↗
PubMed1986

Immunoreactivity for S-100 protein in dendritic and in lymphocyte-like cells in human lymphoid tissues.

S-100 protein is an immunohistochemical marker for a subset of dendritic cells, the interdigitating reticulum cells (IDRCs), which are mainly located in T-dependent areas of lymphoid tissues. In the present study we have investigated the distribution of S-100-positive cells in lymph nodes, spleen, thymus and peripheral blood of normal subjects. Immunoreactivity for S-100 protein was demonstrated in large cells with dendritic morphology and in small lymphocyte-like cells present in the lymph node paracortex, thymic medulla, splenic periarterial lymphatic sheaths (PALS) and in peripheral blood. S-100-positive lymphocyte-like cells were frequently detected around high endothelial venules (HEV) and were present in numbers comparable to those of S-100-positive IDRCs. Immunoelectron microscopy confirmed the existence of positive cells with lymphoid morphology and revealed that the intracellular distribution of the immunoreaction product was similar in lymphoid and dendritic cells. Further characterization of S-100-positive cells demonstrated that both lymphoid and dendritic cells were unreactive with a large panel of monocytic and macrophage markers.

Antigens, Differentiation, T-Lymphocyte↗
PubMed1985

The Omenn's syndrome: histological, immunohistochemical and ultrastructural evidence for a partial T cell deficiency evolving in an abnormal proliferation of T lymphocytes and S-100 +/T-6 + Langerhans-like cells.

A 7 month old female infant was affected by a rapidly fatal familial disease highly reminiscent of Omenn's syndrome. She presented with widespread eczematous lesions, hepatosplenomegaly, superficial lymphadenopathy, peripheral blood lymphocytosis, eosinophilia and hyper-IgE. An axillary lymph node was involved by a marked proliferation of T-3 +/T-10-- lymphocytes admixed with S-100+/T-6+/Leu-3a+/Ia + reticular cells which lacked typical LC granules; cell suspension study revealed that 90%-96% of the lymph node cells were T-11+/T-3+ lymphocytes characterized by low expression of Leu-3a and T-8 antigens and by high expression of Ia antigens (52%). Peripheral blood T lymphocytes exhibited a similar distribution of surface phenotypes. The patient died of interstitial pneumonia and an autopsy was performed. The thymus was markedly atrophic and completely devoid of lymphocytes. The peri-arteriolar lymphoid sheets of the spleen were poorly developed and were mainly composed of T-8+ lymphocytes. The mediastinal nodes were rudimentary and were populated by T-3+/T-10+ lymphocytes with low expression of Leu-3a and T-8 antigens. Our results raise the possibility that Omenn's syndrome is a peculiar primary immunodeficiency in which, despite early thymic involution, some abnormal T lymphocytes still develop in the peripheral lymphoid organs. Antigenic triggering of these cells might result in prominent proliferations of T lymphocytes and Langerhans-like cells which lead to the clinical manifestation of the disease.

Antigens, Differentiation, T-Lymphocyte↗
PubMed1985

Systemic lymphadenopathy (LAS) in intravenous drug abusers. Histology, immunohistochemistry and electron microscopy: pathogenic correlations.

In the present study we have evaluated the histological, immunohistochemical, ultrastructural and cell surface phenotypic features of lymph nodes from 19 intravenous drug abusers and two homosexual men with persistent lymphadenopathy syndrome and from six control patients. Our investigation has demonstrated that the lymphadenopathy of drug abusers is characterized by: (a) specific histological features with evidence of evolution from an initial hyperplastic-reactive to a late regressive-destructive stage; (b) T-cell surface phenotype distribution similar to that in the peripheral blood of homosexuals; (c) peculiar infiltration of the germinal centres by T8+ cells and by S-100+, T6+ interdigitating reticulum-like cells; (d) electron microscopic features indicating the presence of virus bodies in lymph node cells and in the intercellular spaces. These data suggest that the lymphadenopathy of drug abusers and homosexuals are similar pathological conditions with characteristic features which allow histological differentiation of this entity from those found in other viral infections.

Female↗
PubMed1984

Peripheral T cell lymphoma in adults: morphological and phenotypical study of four cases.

In the present study we investigated the lymph node morphology and distribution of cell surface phenotypes in four cases of adult peripheral T cell lymphoma. Histologically, the tumors were classified as T zone lymphoma, T cell lymphoma with large multilobated nuclei and T cell immunoblastic sarcoma. In the T zone lymphoma the neoplastic lymphocytes were E+ (90%) and exhibited intensive focal staining for acid phosphatase (93%) and acid esterase (92%); the phenotype distribution revealed low expression of the T-3 antigen (49%), selective expression of the T-4 antigen (72%) and poor expression of T-6 (10%) and T-10 antigens (22%). Some of these features are present in normal and in neoplastic immature T cells. In the remaining three cases the majority of lymph node cells were E+ (59-75%), T-3+ (67-80%) and T-8+ (43-55%). A distinctive feature of the T cell immunoblastic sarcoma was the presence of high percentages of DR+ cells (62%; 63%). Thus our results indicate that the morphological heterogeneity of peripheral T cell lymphoma is also paralleled by a variety of surface phenotypes and that phenotype studies may provide a useful contribution to identification and accurate classification of peripheral T cell neoplasms.

Adult↗
PubMed1984

S-100+ lymph node neoplasm. Report of a case with histological AL and immunological features intermediate between T cell lymphoma and malignant histiocytosis.

A 16-yr-old white female was affected by continuous fever, pancytopenia with relative increase of T-8 lymphocytes, severe bone marrow hypoplasia, generalized lymphadenomegaly and splenomegaly. A first lymph node biopsy, obtained at the onset of the disease, was involved by a paracortical tumor with some S-100+ "lymphocyte-like" cells in the neoplastic areas; in the cell suspension, 70-80% of cells were E4+/E37+ lymphocytes with prevalent expression of the T-8 phenotype (52%). A second lymph node biopsy, obtained five months later, was involved by a diffuse proliferation of S-100+ cells with high mitotic activity; in the cell suspension, the majority of cells were E-/T-11+/T-3+/T-8+. At the TEM level, the neoplastic cells were characterized by regular or indented nuclei with finely dispersed chromatin and by regular or indented nuclei with finely dispersed chromatin and by irregular cytoplasmic profiles with thick pseudopodia-like projections. The possibility is discussed that this neoplasm may share some similarities with the T-gamma lymphoma being part of a poorly described group of tumors with intermediate features between T cell lymphoma and malignant histiocytosis.

Adolescent↗
PubMed1984

T-lymphocyte subsets in human lymph nodes: relative increase of OKT-8+ cells in neoplastic and reactive B-cell proliferation.

Cell suspensions obtained from 54 human lymph nodes involved by different pathological conditions were characterized by conventional markers and by the OKT-3, OKT-4, OKT-8, OKIa-1, and OKM-1 monoclonal antibodies. In 18 cases of reactive lymphoid hyperplasia, the majority of lymph node cells were mature T lymphocytes (E-RFC = 56 +/- 9%; OKT-3+ = 63 +/- 10%); among T-cell subsets, OKT-4+ cells were 49 +/- 8% whereas OKT-8+ cells were 21 +/- 8% (T4/T8 = 2.7 +/- 1.1). This distribution of T-cell phenotypes was not similar in the different histological types of reactive lymphoid hyperplasia. In fact, an increase in the percentage of OKT-8+ cells (25 +/- 9%; P less than 0.05) and a decrease in the values of the T4/T8 ratio (2.1 +/- 1.0; P less than 0.05) were observed in 9 cases of reactive lymphoid hyperplasia of follicular type when they were compared to the mixed and sinus types. In 13 lymph nodes involved by B-cell lymphoma, the percentage of T lymphocytes was markedly reduced (E-RFC = 21 +/- 12%; OKT-3+ = 27 +/- 18%) and the percentage of OKIa-1+ cells (51 +/- 15%) was significantly (P less than 0.01) increased as compared to reactive nodes; in addition, in these cell suspensions, an increase in the relative proportion of OKT-8+ cells (T4/T8 = 1.4 +/- 0.7; P less than 0.01) could also be demonstrated. Finally, a clear prevalence of OKT-4+ cells on OKT-8+ cells was demonstrated in 5 cases of tuberculous lymphadenitis (T4/T8 = 3.9 +/- 1.5; NS) and in 18 cases of Hodgkin's disease (T4/T8 = 4.2 +/- 2.0; P less than 0.01). In tuberculous lymphadenitis, a significant increase (P less than 0.01) in the percentage of OKM-1+ cells could also be demonstrated.

Antibodies, Monoclonal↗
PubMed1983

Hairy cell leukemia: absence of natural killer activity and of interleukin 1 release in OKM-1+ spleen hairy cells.

Phenotypic characterization by monoclonal antibodies of spleen cells obtained from three spleens involved by hairy cell leukemia (about 90% of cells with intracytoplasmic tartrate-resistant acid phosphatase) indicated that the hairy cells are OKT-3-, OKM-1+, and OKIa1+. Neoplastic cells obtained from two lymph nodes involved by B-cell lymphoma were found to be OKT-3-, OKM-1-, and OKIa1+. Functional characterization of the hairy cells present in the spleen indicated that they lack NK activity and do not release Interleukin 1. In fact, spleen hairy cells were not lytic against K-562 tumor cells in a short-term 51Cr-release assay and did not release Interleukin 1 in culture supernatants even after LPS stimulation. In normal individuals, both these cell functions are expressed by subpopulations of OKM-1+ cells.

Adult↗
PubMed1983

The human thymus in ageing: histologic involution paralleled by increased mitogen response and by enrichment of OKT3+ lymphocytes.

In the present study, based on 24 individuals aged 5-61 years, the histological pattern of the thymus has been determined and correlated to the thymus lymphocyte in-vitro responses to phytohaemagglutinin (PHA) and concanavalin A (Con A). It has been found that lymphocytes from histologically involuted thymus were significantly more responsive to PHA and Con A stimulation than lymphocytes from histologically normal thymus. These data indicate that thymus age-dependent involution is associated with increased lymphocyte in-vitro reactivity. In addition, in 10 cases the relative proportions of the thymus lymphocyte subpopulations have been determined by the use of monoclonal antibodies OKT3, OKT4, OKT6 and OKT8. These results have been correlated to the histology of the organ and to the mitogen responsiveness of thymus lymphocytes. In normal thymus the majority of the cells were OKT6+, while there were lower numbers were OKT3+. However, in involuted thymus, OKT3+ lymphocytes prevailed over OKT6+ cells. Furthermore, a direct relationship between the proportion of OKT3+ lymphocytes and the response to mitogens has been observed. These findings indicate that the increased mitogen response noticed in histologically involuted thymus is accompanied by an OKT3+-cell enrichment which is paralleled by a depletion of OKT6+ cells.

Adolescent↗
PubMedDate not supplied

Scleroderma fibroblasts constitutively express the long pentraxin PTX3.

OBJECTIVE: PTX3 is a secreted molecule which consists of a C-terminal domain similar to classical pentraxins (e.g. C-reactive protein) and of an unrelated N-terminal domain. Unlike the classical pentraxins, PTX3 is expressed in response to IL-1beta and TNF-alpha but not to IL-6. The present study was designed to investigate the expression of PTX3 in normal and scleroderma fibroblasts. METHODS: Normal and SSc fibroblasts were cultured in the presence and absence of inflammatory cytokines. PTX3 mRNA expression in fibroblasts was evaluated by Northern analysis. PTX3 protein levels in fibroblast culture medium were estimated by ELISA. RESULTS: Normal fibroblasts were induced to express high levels of P7X3 mRNA by IL-1beta and TNF-alpha but not by other cytokines or growth factors. Scleroderma fibroblasts, unlike normal fibroblasts, constitutively expressed high levels of PTX3 in the absence of deliberate stimulation. The constitutive expression of PTX3 in SSc fibroblasts was not modified by anti-TNF-alpha antibodies or IL-1 receptor antagonist. In contrast, IFN-gamma and TGF-beta inhibited the constitutive but not the stimulated expression of PTX3 in SSc fibroblasts. CONCLUSIONS: PTX3 is a main feature of activated scleroderma fibroblasts.

C-Reactive Protein↗