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G Palestro

Publications and source records attributed to G Palestro.

At least 73 records · Page 4Linked to original sources
PubMed1990

Infiltrating leukocyte populations and T-lymphocyte subsets in head and neck squamous cell carcinomas from patients receiving perilymphatic injections of recombinant interleukin 2. A pathologic and immunophenotypic study.

Nine patients with squamous cell carcinoma of the oral cavity and oropharynx underwent preoperative perilymphatic administration of recombinant interleukin 2 (rIL-2). A more marked eosinophil and lymphocyte infiltration and more extensive edema than in 13 untreated cases were observed in surgical specimens. Necrosis was present in five of nine cases, but involved no more than 10% of the neoplastic tissue; in three of nine cases, characteristic necrotic changes with intense eosinophil infiltration possibly induced by lymphokines involved the peritumoral soft tissues. Of the tumor-infiltrating lymphocytes, T-lymphocytes (mostly CD4+ cells) prevailed over B-lymphocytes. CD4+ and CD8+ cells were mainly located close to the neoplastic sheets. Moderate amounts of CD38+ and CD11c+ cells (macrophages) and few CD16+ and CD56+ lymphocytes were found in all cases. CD25+ and LAK1+ cells were significantly more numerous in treated than in untreated cases. This suggests that local administration of rIL-2 induces an increase in activated T-lymphocyte subsets infiltrating the neoplastic tissue, thus eliciting a tumor-specific T-lymphocyte reactivity.

Adult↗
PubMed1990

Heterogeneous subgroups among malignant diffuse small B cell lymphomas. A combined nucleometric and immunocytologic study.

The degree of heterogeneity among subtypes was evaluated in 39 of the most frequent malignant, diffusely growing small B cell lymphomas by a combination of morphometry, automated image analysis, and immunocytologic techniques. Cluster analysis of nuclear profile parameters, including nuclear area, circularity factor, and chromatin distribution pattern, distinguished 3 groups. Each group was characterized by the preponderance of certain nuclear profile types, i.e. (a) small, rather regular (roundish) and dark staining (typical small lymphocytic lymphomas and immunocytomas); (b) small to intermediate size, rather regular (roundish) and pale staining (small to intermediate size variant); or (c) small to intermediate size, irregular, rather pale staining (diffuse follicular small cleaved cell (centrocytic) lymphomas and, probably, polymorphous immunocytomas). Group 3 was clearly distinct from the rest, but groups 1 and 2 also differed significantly. Every case displayed a mixture of the 13 registered nuclear profile types. Lymphoid cells with similar nuclear profile features occurred in B cell zones of non-neoplastic lymph nodes. Frequency distribution of nuclear profile parameters significantly differed from one lymphoma group to another. However, there were considerable overlaps. No clear correlation was found between nuclear profile types and immunophenotypes. Cellular surface antigen patterns showed an extensive intra- and inter-case variability. The findings support the notion of a certain individuality of malignant B cell lymphomas and of a marked heterogeneity among their subtypes.

Adult↗
PubMed1990

Immunoglobulin and Myc gene structure in lymphnode biopsies from HIV-positive patients with LAS and lymphoma.

The pattern of immunoglobulin (Ig) gene rearrangement and the genomic structure of the Myc locus were investigated in the DNA of 20 lymphnode biopsies of patients suffering from lymphoadenopathy-associated syndrome (LAS) and from 3 patients with Burkitt's lymphoma. Although polyclonality was the prevalent pattern of Ig gene rearrangement observed in LAS, in 30% of the cases discrete bands of Ig heavy chain gene rearrangement were identifiable due to the presence of monoclonal or oligoclonal cell populations. However, structural alterations of the Myc gene were not detected in any cases. As expected, in all three Burkitt's lymphomas studied, the lymphnode DNA displayed a clonal pattern of Ig heavy chain gene rearrangement. The Myc was altered in two cases, which presented a truncation of the gene beginning within a very short region of the first intron. By contrast, the breakpoint positions on chromosome 14 mapped in different regions of the Ig loci, which in both cases involved the switch (SH) area. Data confirm the relatively common occurrence of oligoclonal expansions within B cells in LAS and the frequent involvement of the Myc oncogene in the process of lymphomagenesis in individuals positive for human immunodeficiency virus (HIV).

AIDS-Related Complex↗
PubMed1989

[Phenotype study of varieties of carcinomas originating in the oro-pharyngo-laryngeal mucosa. Anatomo-clinical considerations].

An immunohistological analysis with a panel of monoclonal and polyclonal antibodies was performed in 20 cases of squamous cell carcinoma originating in the oral cavity, oropharynx and larynx. The epithelial antigens were detected in all cases with variable patterns of positivity: cytokeratins and epithelial membrane antigen were positive in a high number of neoplastic cells in the carcinomas with a high grade of differentiation, whereas a lesser number of positive cells was observed in the poorly differentiated carcinomas. On the contrary the tissue polypeptide antigen was detected in a considerable number of neoplastic cells in the poorly differentiated carcinomas as well as in the fields with basal and cylindric cells. Mesenchymal antigens were negative in all tumors, except one case with pseudosarcomatous patterns, which was vimentin-positive. The detection of an immunohistochemical spectrum of squamous cell carcinomas may give further information on the biological characteristics, and consent to identify subtypes with a different histogenesis.

Aged↗
PubMed1988

Recognition by monoclonal antibody CB02 of a surface molecule shared by B lymphocytes and a discrete large granular lymphocyte subset with cytotoxic activity.

Here we present the characterization of a new antigen called CB02 which is present on B cells and on a subset of CD16+ large granular lymphocytes. The pattern of reactivity of this molecule on normal cells, B cell lines, leukemic cells and tissue sections suggests that the CB02 molecule is expressed by B cells before isotype switch and is lost during terminal differentiation. Furthermore, the CB02+ population encompassed natural killer (NK) cells exerting significant cytotoxic activity: in fact, peripheral blood lymphocytes depleted of the CB02+ subset display a marked reduction in NK activity.

Animals↗
PubMed1987

Primary lymphomas of the brain: a clinico-pathologic review of 37 cases.

The clinico-pathologic data of 37 primary lymphomas of the brain were retrospectively reviewed. The tumors were classified according to the Kiel classification and the Working Formulation System. They represented 1.02% of all primary intracranial tumors of our series. The radiologic prediction appeared to be difficult: the suspicion was maximal when the absence of pathologic vessels at angiography occurred in a meningioma-like lesion at CT. Median survival was 4.53 months in the 16 cases who underwent surgery only versus 25.7 months in the 8 cases operated and irradiated with 40-60 Gy (p less than 0.01). The prognosis of lymphomas of the CNS, even if radioresponsive tumors, remains poor. Most patients relapse after treatment, most often locally in the brain, with a variable frequency of spinal or systemic localization.

Adolescent↗
PubMed1987

Relationship between structure and T-lymphocyte maturation in human thymomas. Enzyme histochemical and immunohistological studies.

Twenty-six human thymomas were studied in an attempt to correlate their morphological appearance with the type and degree of T-lymphocyte maturation, as determined by acid alpha-naphthyl-acetate esterase (ANAE) activity and immunological analysis. Four normal human thymuses were used for purposes of comparison. Two morphological patterns were identified in the thymomas. The distinction was based largely on similarities between the neoplastic epithelial cells and normal cortical and medullary epithelial cells, and on the relative proportions of epithelial cells and lymphocytes. By these criteria "medullary" and "cortical" patterns were identified. In several thymomas both patterns were present in the same tumor ("mixed-type pattern"), producing alternating dark cortical-like areas and lighter foci of medullary differentiation. A good correlation was found between the two patterns and the phenotype of the T-associated lymphoid component. ANAE activity, which was completely lacking in normal cortical thymocytes, was almost absent in the phenotypically immature T-cells of cortical-type thymomas. By contrast, in the medullary-type thymomas, T-cells showed immunological features in common with medullary thymocytes. This was characterized by strong ANAE activity in the majority of cells with a staining pattern corresponding to that of peripheral T-lymphocytes. In addition, most of the proliferating epithelial cells in medullary-type thymomas stained strongly with anti-cytokeratin and anti-epidermal-type keratin antisera. In the mixed-type thymomas the epithelial cell morphology and the immunohistochemical and enzymic features of the T-cells were found to be closely related to the respective cortical--or medullary-like areas. It was concluded that the various characteristics of normal thymic cortex and medulla studied are also present in thymomas. In particular, in medullar-type thymomas the presence of many of the features of normal thymic medulla, such as a squamous cell component, macrophages and interdigitating reticulum cells, may constitute a microenvironment which operates actively in T-cell education. This may account for the functional activities, characteristic of peripheral T-lymphocytes, which T-lymphocytes attain in these thymomas.

Adult↗
PubMed1987

Immunologic cell markers of peripheral blood and lymph node lymphocytes in chronic lymphocytic leukemia.

The immunologic phenotype of the lymphocytes of 100 patients with chronic lymphocytic leukaemia (CLL) was investigated. Peripheral blood lymphocytes (PBL) were examined in all cases; in 46 patients with lymphadenopathy, a lymph node was biopsied and the histologic and immunologic patterns were assessed: 24 had a lymphocytic-lymphoplasmocytoid histology and 22 the follicular variant of lymphocytic lymphoma (mantle zone lymphoma, MZL). For comparison, lymph node suspensions from 19 patients with non-leukemic centrocytic lymphoma (CCL) were also studied. Significant differences in the PBL immunologic features were found between stage O and stage I patients. The phenotype of the lymphocytes of patients with lymphocytic histology was similar to that of stage 0 CLL patients, whereas major differences were found between these patients and those with mantle zone histology. This enables these patients to be recognized easily on immunologic grounds.

Antigens, Surface↗
PubMed1987

Acid hydrolases in B-chronic lymphocytic leukemia (B-CLL): a comparison with normal peripheral B lymphocytes and normal B-cell subset with the phenotype of B-leukaemic cells.

The acid phosphatase (AP), beta-glucuronidase (BG), and alpha-naphthyl-acetate esterase (ANAE) distribution and the morphology of stage 0 B-CLL lymphocytes were studied. The results were compared with the same hydrolase equipment and morphology of normal B-cell populations showing the B-CLL-like phenotype, and thus regardable as the possible counterpart of leukaemic cells. The functional and structural characters of the former were strikingly different from those of the latter. In fact the normal B-cell population with B-CLL-like phenotype showed an homogeneous enzyme pattern with predominant ANAE and a strictly lymphocytic cell morphology. In contrast, the leukaemic cells showed various and unrelated morphological and cytochemical features, thus forming apparent subgroups of B-CLL. The development of an irregular "switch on" mechanism in the blocked malignant cell clone, may account for these functional and structural maturation discrepancies. Moreover, the fact that in the leukaemic cells ANAE activity could be demonstrated only after the appearance of the other hydrolases, makes it a marker of functionally differentiated B lymphocytes.

Acid Phosphatase↗
PubMed1987

Immunohistochemical evidence of active thymocyte proliferation in thymoma. Its possible role in the pathogenesis of autoimmune diseases.

Eight cases of human thymoma have been analyzed on cryostat sections with the monoclonal antibody Ki67, which reacts with cells in the proliferative phases of the cell cycle. The aim was to assess the proportion of proliferating thymocytes among lymphoid cells in the thymoma samples. In all cases a large number of cells (mean, 58.75%; range, 35-80%), recognized as thymocytes by morphology and lack of cytokeratin expression in a combined immunohistochemical assay, exhibited nuclear Ki67 staining. These findings differ from the reactivity pattern observed in age-matched nonneoplastic thymuses where lower growth activity of cortical thymocytes was observed (15-20% Ki67+ cells). Intensive thymocyte proliferation in thymomas may represent one of the factors which lead to autoimmunity in myasthenia gravis and thymomas.

Adult↗
PubMed1986

Thymomas. A review of 169 cases, with particular reference to results of surgical treatment.

One hundred sixty-five patients with surgically treated thymoma were followed over 28 years; 73% had myasthenia gravis at presentation. Invasiveness was based on macroscopic findings at operation. Postsurgical radiotherapy or chemotherapy were not routinely used. Overall survival was 84%, 79%, and 65% at 3, 5, and 10 years, respectively. Patients with invasive thymoma survived for a shorter period than patients with noninvasive tumors (67% versus 85% at 5 years); when radical excision was possible, no difference was detectable between the two groups. Patients with subtotally resected or only biopsied invasive thymomas survived 59% and 42% at 5 years, respectively. Lymphoepithelial cases had the worst prognosis of the histologic types considered. Myasthenia gravis did not adversely affect survival. Surgery is the basic treatment of thymomas. Macroscopic invasiveness and degree of excision judged by the surgeon have prognostic value and are reliable criteria of malignancy. Radiotherapy and chemotherapy may be effective, but their use should be limited to controlled trials.

Adolescent↗
PubMed1986

Utility of immunohistochemical techniques in identifying various differentiation stages of T and B cell lineage and the related neoplastic transformed cells.

The lymphoid tissue provides the most productive conditions to the application of immunohistochemical techniques. This tissue is composed of many B and T phenotypically different cell populations ranging from stem cells to completely differentiated lymphocytes which can be identified by using monoclonal antibodies. These techniques also are of great help in classifying the malignant lymphocyte counterparts and, thus, in defining diagnostic and prognostic characters of different lymphomas/leukaemias.

Antibodies, Monoclonal↗
PubMed1985

Immunohistological evidences of cortical and medullary differentiation in thymoma.

The phenotypical characteristics of human epithelial and lymphoid cells have been studied with immunohistochemical methods on frozen sections of 12 thymomas. On the basis of the cytohistological characteristics of thymoma epithelial cells (EC) the thymomas were divided in cortical, medullary and mixed types, according to recently developed light microscopical criteria. When tested with a series of monoclonal antibodies, thymoma EC were all stained by the antibody Ki-M3 (as in the thymus), but reacted with anti-HLA-DR, anti-HLA-A,B,C and with a new monoclonal antibody to cortical EC, 21A6, to a lesser extent and with weaker, variable intensity in comparison with the normal thymus. Cortical type thymomas were most reactive and the medullary type almost negative. Thymomas, like normal thymus showed different immunoreactivity patterns with antibodies to prekeratins of different specificities. Cortical type thymomas and areas in mixed thymoma showed an EC staining with the antibody to non-squamous type keratin (35 beta H11) whereas medullary type thymomas and areas showed staining with antibodies to squamous-type keratin (34 beta E12-IV/82) in addition. Lymphoid cells with cortical (OKT6+, Leu 1 weakly+, Leu 2a+, Leu 3a+) or mature medullary (OKT6-, Leu 1 strongly+, Leu 2a or Leu 3a+) phenotype were found to colonize tumours with different EC types. These immunohistochemical findings largely confirm our earlier cytological distinction of thymoma EC. In addition important differences have been observed in neoplastic cortical EC concerning the HLA-DR and 21A6 immunoreactivity that may be intimately related to the neoplastic process and paraneoplastic immune phenomena.

Antibodies, Monoclonal↗
PubMed1984

Signet ring cell lymphoma in salivary gland. An immunohistochemical and ultrastructural study.

A case of recurrent signet ring cell lymphoma involving a salivary gland is reported. The tumour was centroblastic-centrocytic nodular and diffuse. The cells were vacuolated, oil red, Sudan III, PAS and Alcian blue negative. They displayed the Ia-like antigen but were negative for SIg. Ultrastructurally the vacuoles appeared empty or containing residual membrane and/or myelinoid bodies. Sometimes microvesicles were found in them. The vacuoles were mainly located in the Golgi area but they were also found in mitochondria. Cytoplasmic bodies containing microvesicles were also seen. The case is compared with those of the literature and the significance of the vacuoles is discussed.

Aged↗
PubMed1983

Prominent plasmacytic differentiation in the recurrence of a parotid immunocytoma. A morphologic and immunohistochemical study.

We report and discuss a case consisting of 2 lesions that developed at different times in the same parotid gland. Although the first lesion showed morphologic features similar to those of the benign lymphoepithelial lesion, a monotypic IgM/K pattern was also revealed by the immunoperoxidase method in its lymphoid infiltrates. Thus, on cytologic grounds, the first lesion was classified as lymphoplasmacytic immunocytoma (according to Kiel criteria). In the second lesion, which recurred 3 years later, the prominent feature was a marked predominance of plasma cells with the same monoclonal IgM/K as the preceding lymphoma. These findings suggests that a B-lymphomatous cell monoclone may undergo morphologic maturation along the lineage of its competence. Secondly, they indicate that every case of benign lymphoepithelial lesion of the salivary glands should undergo thorough immunologic evaluation to exclude the possibility of signs of precocious lymphomatous transformation.

Adult↗
PubMed1983

Immunohistochemical and enzyme histochemical contributions to the problem concerning the role of the thymus in the pathogenesis of myasthenia gravis.

Normal fetal and postnatal thymuses, as well as thymuses from patients with myasthenia gravis (MG), were investigated by immunohistochemical and enzyme histochemical techniques and their morphology reviewed. Intrathymic B-cells, detected by ATPase activity, were found to be markedly increased in number in MG thymuses. They were scattered in the medulla and accumulated around the junctional and medullary vessels and Hassall's corpuscles (HCs). Large epithelial cells, singly or within HCs, were found to be unevenly distributed in the medulla of all the thymuses examined. The striated muscle-like nature of some of these cells was revealed by the presence of myoglobin in their cytoplasm. In myasthenics these cells and small developing HCs characteristically surrounded lymph follicles and were in direct contact with the expanded cap of the follicle mantle, without interposition of reticulin fibres. The close association of immune reactive foci (lymphoid follicles, junctional and medullary vessels, and HCs) with structures involved in autoimmune responses in the thymus (muscle-like and true myoid cells, HCs) strongly suggests that the autoimmune reactions against AChR (acetylcholine receptor) and other muscular components, which constitute the basic defects in myasthenia gravis, may begin in the thymus.

Adenosine Triphosphatases↗