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F Facchetti

Publications and source records attributed to F Facchetti.

At least 91 records · Page 5Linked to original sources
PubMed1993

Generalized melanosis associated with malignant melanoma: unusual histologic appearance.

A case of generalized melanosis associated with malignant melanoma, characterized by up-to-date, previously undescribed histologic findings, is reported. Markedly dilated dermal lymphatics with features resembling secondary lymphangioma were found. We speculate that a further mechanism, as well as those previously reported in the literature, could be operative in the pathogenesis of this disorder of altered pigmentation.

Aged↗
PubMed1993

Expression of cell adhesion molecules in jejunum biopsies of children with coeliac disease.

The composition of inflammatory cells as well as the expression of cell adhesion molecules (LFA-1/CD11a, ICAM-1/CD54, CD36) in jejunal biopsies from children with active, untreated coeliac disease (CD) has been analyzed and compared with control biopsies. In CD the number of intraepithelial and lamina propria T cells was greater than in controls. ICAM-1 was found on most cells in the lamina propria; many of them expressed LFA-1 as well. In contrast, no ICAM-1+ and a few LFA-1+ cells were noticed in the epithelium. The brush border from control biopsies reacted with HLADR and anti-CD36. In CD, de novo expression of HLADR was found in the cytoplasm of villous and cryptal enterocytes in contrast, CD36 disappeared from the brush border and no expression of ICAM-1 on the inflamed epithelium was noticed. The results indicate that adhesion molecules other than LFA-1, ICAM-1 and CD36 may be involved in the cellular interactions occurring in the intraepithelial compartment in CD; the lack of ICAM-1 and the reduced expression of LFA-1 on intraepithelial lymphocytes might reflect a defective activation of these cells. Several macrophages were found in the lamina propria in cases of CD; some of them were located beneath the surface epithelium, showed a spindle/dendritic morphology, and expressed the HLADR+, CD36+, CD11a- phenotype. These cells might be stimulated by luminal antigens and might play an important role in subsequent activation of T cells in the lamina propria.

Adolescent↗
PubMed1992

Sinus histiocytosis with massive lymphoadenopathy (Rosai-Dorfman disease). Clinico-pathological analysis of a paediatric case.

Histochemical and immunohistochemical studies performed in only a few cases of sinus histiocytosis with massive lymphoadenopathy (SHML) indicated that SHML cells belong to the macrophage--histiocyte system, though their exact origin is still uncertain. We analyzed the morphological, antigenic and enzymatic characteristics of the histiocyte-like cells in one paediatric case of SHML (also named Rosai-Dorfman disease). The SHML cells expressed the S-100 protein, lectins concanavalin A, peanut agglutinin and monocyte-macrophage related antigens CD 11c, CD 14, CD 33, CD 68 and LN 5. Reactivity with other anti-macrophage antibodies (MAC387, lysozyme, alpha-1 anti-chymotrypsin) was variable. The CD1a antigen was present only in scattered cells, whereas HLA-DR and the HLA-DR associated invariant chain were absent. Cytochemistry demonstrated an intense activity of acid phosphatase and non specific esterase of SHML cells. A large amount of medium sized mononuclear cells were located in the sinuses and intersinusoidal tissue. Our findings suggest that SHML cells have intermediate features between phagocytes and Langerhans cells/interdigitating reticulum cells. The heterogeneity of marker expression on SHML cells might be related to the local content of factors (e.g., cytokines), capable of modulating the phenotype of monocyted and derived cells.

Child↗
PubMed1992

Immunophenotypic characterization of the cell infiltrate in five cases of sinus histiocytosis with massive lymphadenopathy (Rosai-Dorfman disease).

Little is known about the nature of the large intrasinusoidal cells exhibiting cytophagocytosis, which are the histologic hallmark of sinus histiocytosis with massive lymphadenopathy (SHML) (Rosai-Dorfman disease). Using a broad panel of monoclonal and polyclonal antibodies, we analyzed the immunophenotype of the cell infiltrates in seven lymph node biopsy specimens from five cases of SHML. The SHML cells constantly expressed the S-100 protein, concanavalin agglutinin and peanut agglutinin lectins, and monocyte-macrophage-associated antigens CD 11c, CD 14, CD 33, CD 68, and LN 5. Labeling with other antimacrophage antibodies was extremely variable, with some (MAC 387, lysozyme) restricted to clusters of SHML cells and others (CD11b, CD 36, alpha-1-antichymotrypsin) staining only scattered cells. The CD 1a antigen was found on some cells in only one case, whereas HLA-DR and the HLA-DR-associated invariant chains were absent. The heterogeneity of SHML cell marker expression might be related to the local content of factors (eg, cytokines) capable of modulating the phenotype of monocytes and derived cells. All cases presented with huge amounts of medium-sized mononuclear cells accumulated in the sinuses and intersinusoidal tissue. These cells expressed the S-100-/CD 11b+/CD 11c+/CD 14+/CD 16+/CD 33+/CD 36+/lysozyme+/MAC 387+/HLA-DR+ phenotype. These recently immigrated monocytes might represent the immediate precursors of SHML cells.

Adolescent↗
PubMed1992

Neoplastic epithelial cells in a subset of human thymomas express the B cell-associated CD20 antigen.

A series of 36 human thymomas have been immunohistochemically analyzed using a panel of antibodies recognizing B-cell markers including CD20. Most thymomas exhibiting the cortical pattern, according to the criteria of Marino and Muller-Hermelink, were characterized by areas of medullary differentiation containing variable numbers of CD20+ B lymphocytes, thus mimicking the medulla of normal thymus. On the other hand, B cells were absent or rare in thymomas recognized as mixed using the same morphological criteria. Surprisingly, we observed in most mixed thymomas variable numbers of CD20+ spindle cells, characterized by long slender processes. Using double-marker analysis we could demonstrate the epithelial nature of these cells (expression of keratin and lack of lymphoid and B-cell-related markers). The immunoreactivity of thymoma epithelial cells with L26, an antibody widely used in the characterization of B-cell lymphomas, can represent a drawback of practical relevance in the differential diagnosis of mediastinal tumors.

Antibodies, Monoclonal↗
PubMed1992

Suppurative granulomatous lymphadenitis. Immunohistochemical evidence for a B-cell-associated granuloma.

The cellular composition of suppurative granulomas was investigated by the application of monoclonal and polyclonal antibodies to paraffin sections and compared with nonsuppurative, hypersensitivity-type granulomas. Macrophages, T cells, and dendritic cells showed a similar distribution in both types of granulomas. In addition to the presence of granulocytes, a major difference between suppurative granulomas and hypersensitive-type granulomas concerned their relationship with B lymphocytes. Hypersensitive-type granulomas were surrounded by small mantle B cells, but they did not contain any B lymphocytes. In contrast, variable numbers of B cells were found either at the periphery or in the center of suppurative granulomas. In view of their morphology (medium size, pale cytoplasm, irregular nuclear shape) and phenotype (L26 +/LN1 -/MB2 +/MT2 +) these B lymphocytes closely resembled monocytoid B cells. The monocytoid B cells might have a role in the recruitment of polymorphonuclear granulocytes and in the development of the necrosis, which occur within suppurative granulomas.

Acid Phosphatase↗
PubMed1992

[The orodental findings in the Ehlers-Danlos syndrome. A report of 2 clinical cases].

Ehlers-Danlos syndrome (EDs) is a hereditary disorder of the connective tissue. Its clinical expression is variable and there are many difficulties in recognizing the disease because of the presence of eleven different forms. In this study the authors describe the oral manifestations in two cases of EDs. The children show hyperelasticity of the skin, easy bruisability, hyperextensibility of the joints, several dental manifestations: periodontitis, many caries, supernumerary teeth or hypodontia.

Biopsy↗
PubMed1992

Multiple scattered granulomatous skin lesions in cat scratch disease.

We report a patient with cat scratch disease who presented with multiple scattered nodular lesions on the legs. Examination of skin biopsy specimens revealed a granulomatous pattern. In our opinion, this is a previously undescribed secondary cutaneous reaction of cat scratch disease. The pathogenesis of this reaction is unclear but some data suggest that the eruption might be caused by a hematogenous spread of cat scratch disease bacteria to the skin. Pathogenetic relationships with so-called bacillary angiomatosis, recently described in patients with acquired immunodeficiency syndrome, are reviewed here.

Cat-Scratch Disease↗
PubMed1991

KP1 (CD 68) staining of malignant melanomas.

The monoclonal antibody KP1, which recognizes the CD 68 antigen on macrophages and myeloid precursors, was tested on 28 malignant (primary and metastatic) melanomas, 28 naevi, and 17 skin biopsies showing either normal (10) or hyperplastic melanocytes (7). Sixteen of 20 primary melanomas and six of eight metastatic melanomas showed variable numbers of KP1 positive tumour cells. All but five benign melanocytic proliferations (two Spitz naevi and three intradermal naevi), as well as normal and hyperplastic melanocytes were negative. These results indicate that difficulties may occur with the use of KP1 in the differential diagnosis between melanomas and neoplasms derived from histiocytes-macrophages, and that the expression of CD 68 antigen might be related to tumour progression in melanocytic cells.

Antibodies, Monoclonal↗
PubMed1990

Distribution of non-lymphoid, inflammatory cells in chronic HBV infection.

Non-lymphoid cells play a key role in the initiation and maintenance of cellular immune responses. Using in-situ immunohistochemical techniques and a panel of monoclonal antibodies (mcabs) reactive with B5-fixed, paraffin-embedded liver biopsies, we analysed the non-lymphoid cell component in inflammatory infiltrates in 20 cases of chronic hepatitis B virus (HBV) infection. In addition, lymphocyte subsets and HLA-DR antigens were studied. Mcab KP1 labelled scattered Kupffer cells, which variably expressed HLA-DR antigens. Their random distribution and lack of significant topographical association with lymphocytes suggest that classical Kupffer cells do not play a major role in cell-mediated immune reactions. On the other hand, mcab Mac387 was unreactive with normal liver tissue but labelled HLA-DR+ dendritic cells in areas of intralobular inflammation. On (immuno)electron microscopy, these Mac387+ dendritic cells were situated in the Disse space, where they formed close contacts with lymphocytes. Similar dendritic cells were situated at the edge of portal tracts in cases of chronic active, but not chronic persistent hepatitis. Immunostaining on serial frozen sections revealed their close topographical association with cytotoxic/suppressor T-cells, suggesting that Mac387+ HLA-DR+ dendritic cells play an immunomodulatory role in the effector arm of the cellular immune response that takes place in the periphery of portal tracts and the lobular parenchyma, and that involves activation and proliferation of cytotoxic T cells. Finally, large Mac387- HLA-DR+ dendritic cells expressing the LN2 marker were situated amidst helper/inducer T-cells in the centre of severely inflamed portal tracts.(ABSTRACT TRUNCATED AT 250 WORDS)

Antigen-Presenting Cells↗
PubMed1990

Plasmacytoid monocytes in Jessner's lymphocytic infiltration of the skin.

Plasmacytoid monocytes are normal cell constituents of the human lymph node and have been found to form perivascular clusters in a case of lymphocytic infiltration of the skin. This study was undertaken to analyze the occurrence of plasmacytoid monocyte clusters in biopsy specimens from 54 patients with lymphocytic infiltration of the skin using light microscopy and immunohistochemistry. Variably sized clusters of plasmacytoid monocytes were observed in close association with dermal venules in 16 of 54 biopsy specimens and were composed of medium-sized cells, admixed with pyknotic cells and, occasionally, with tangible body macrophages. Immunohistochemistry on paraffin and on frozen sections facilitated the recognition of plasmacytoid monocytes and showed an immunophenotype similar to that observed previously on reactive lymph nodes. It is concluded that, in analogy with reactive lymph nodes, plasmacytoid monocytes represent a common constituent of the skin-associated lymphoid tissue. The striking perivascular distribution and the immunophenotypical characteristics of these monocyte-derived cells suggest they may have a role in the process of lymphocyte recruitment into the skin.

Adult↗
PubMed1990

Leukemia-associated lymph node infiltrates of plasmacytoid monocytes (so-called plasmacytoid T-cells). Evidence for two distinct histological and immunophenotypical patterns.

The medium-sized mononuclear cell with plasmacytoid features, formerly known as "T-associated plasma cell" or "plasmacytoid T cell," has recently been shown to express several myelomonocyte and monocyte-macrophage associated antigens, suggesting a monocytic origin, and it has been renamed "plasmacytoid monocyte." The present study describes the clinical and pathological features of two patients with generalized lymphadenopathy and leukemia (chronic myelomonocytic leukemia in Case 1, and acute non-B, non-T lymphoblastic leukemia in Case 2), and whose lymph node biopsies showed large numbers of plasmacytoid monocytes associated with the leukemic infiltrates. Case 1 was strikingly similar to three previously reported cases of so-called "plasmacytoid T cell" lymphoma, all associated with a myeloproliferative disorder. In our case, the destructive growth pattern of the plasmacytoid monocytes and the de novo expression of CD5 on these cells favored their neoplastic nature; the sharing of some markers of plasmacytoid monocytes with the myelomonocytic infiltrate suggested they were part of the tumoral proliferation. In Case 2, plasmacytoid monocytes displayed an immunophenotype guide similar to that reported in reactive conditions and were antigenically unrelated to the leukemic cells; plasmacytoid monocyte clusters occurred also in the lymphoid parenchyma spared by the leukemic infiltrate. These findings led us to interpret the large numbers of plasmacytoid monocytes in this second case as a tumor-associated host reaction.

Aged↗