Search PubMed⌕ Search

Biomedical subjects

A Gloghini

Publications and source records attributed to A Gloghini.

176 records · Page 10Linked to original sources

Dipeptidylaminopeptidase IV activity in T lymphocyte subsets in B cell non-Hodgkin's lymphomas.

The total T cell population and T cell subsets in ten lymph nodes with reactive lymphoid hyperplasia (RLH) and 23 specimens (21 lymph nodes, one stomach, and one small bowel) involved by histologically and immunohistologically diagnosed B cell non-Hodgkin's lymphomas (NHLs) were determined by reactivity with monoclonal antibodies Leu 4-CD3, Leu 3-CD4, and Leu 2-CD8 in cytospin preparations from cell suspensions. T cell populations were also investigated for the coexpression of dipeptidylaminopeptidase IV (DAP IV) activity, which was visualized simultaneously with cell surface immunostaining by a combined cytochemical and immunocytochemical method. The mean absolute percentage of Leu 4-CD3+ (total T) and Leu 3-CD4+ cell populations was significantly lower in B cell NHL cases than in RLH cases (35% v 54%, P less than .001; 29.5% v 44.4%, P less than .01). No difference in the mean absolute percentage of the Leu 2-CD8+ T cell subset was found between the RLH cases and the B cell NHL cases classified as other than category A as described by the Working Formulation (WF) of NHLs. The relative percentage of Leu 4-CD3+ and Leu 2-CD8+ cells coexpressing DAP IV reactivity was lower in B cell NHL cases than in RLH cases (27.3% v 39.5%, P less than .05; 13.5% v 24.4%, P less than .10). There was no difference in the proportion of Leu 3-CD4+ cells expressing DAP IV reactivity between the NHL and RLH groups (34.5% v 36.1%). Since the mean relative percentage of Leu 2-CD8+ cells expressing DAP IV reactivity in the B cell NHL group in the other than category A according to the WF was lower than that of the RLH group (12.5% v 24.4%), and whereas the mean absolute percentage of total Leu 2-CD8+ cells was similar in the two groups (16.6% and 16.6%), a possible defective role of this Leu 2-CD8+ DAP IV+ subset, at least in B cell NHLs in the other than category A according to the WF, may be hypothesized.

Antibodies, Monoclonal↗

Basement membrane components in lymphoid follicles: immunohistochemical demonstration and relationship to the follicular dendritic cell network.

We analyzed the distribution of two basement membrane components, laminin and type IV collagen, in human reactive and neoplastic lymphoid follicles by using immunoenzymatic and immunofluorescence methods on serial frozen sections from 11 reactive lymph nodes, three palatine tonsils, and 11 immunophenotypically defined B cell non-Hodgkin's lymphomas. The patterns of distribution of these two antigens were compared with that of follicular dendritic reticulum cells (DRCs) as visualized by anti-DRC-1 and anti-desmoplakin 1 and 2 antibodies. Immunostaining for laminin and type IV collagen produced overlapping results. Germinal centers contained some vascular and fiber-like linear staining, but the most striking feature was the presence of a large amount of punctate-granular staining. This staining was present throughout the entire area of most of the germinal centers, although often more densely in the central areas. The stronger punctate-granular staining for laminin, type IV collagen, and desmoplakin 1 and 2 corresponded to the more densely stained areas for DRC-1. Double immunofluorescence assay demonstrated that there was a close similarity between the punctate-granular staining pattern of laminin and the dendritic network of DRC-1-positive cells. In the nine B cell lymphomas of follicular center origin in which DRCs were present, although distributed in different patterns, immunostaining for laminin and type IV collagen could be observed only in those areas showing immunoreactivity for DRC-1. The results of this study suggest that the punctate-granular staining pattern for laminin and type IV collagen is specific for the follicle. This finding may be strictly related to the follicular microenvironment because the pattern of distribution displayed by laminin and type IV collagen seems to be spatially related to the staining pattern of DRCs, as visualized by the anti-DRC-1 and desmoplakins antibodies, both in reactive and neoplastic conditions.

Antibodies, Monoclonal↗

A combined cytochemical and immunocytochemical method for simultaneous visualization of cytoplasmic enzyme reactivity and cell surface antigens in cell suspensions.

Immunocytochemical methods were used in combination with enzyme cytochemistry to visualize simultaneously cytoplasmic enzyme reactivity (for dipeptidyl[amino]peptidase [DAP IV], acid phosphatase [AcP], chloroacetyl esterase [CAE]) and cell surface antigens (Leu-3a, Leu-4, Leu-14, Leu-M1, OKT4, OKT8, OKB7) in cytospin preparations from cell suspensions of human reactive lymphoid tissues (four lymph nodes and three tonsils). Different fixative solutions were tested. Enzyme and immunocytochemical reactions were carried out in different orders of sequence to establish which was the better direction for the combination of the two methods. The following immunocytochemical methods were tested: three stages, avidin-biotin complex, peroxidase-antiperoxidase, alkaline phosphatase-antialkaline phosphatase (APAAP) (using both peroxidase and alkaline phosphatase as labeling enzyme). Acetone or buffered formalin acetone gave the best results both for cytochemical and immunologic reactions. DAP IV and AcP reactivities could be visualized only when cytochemical reactions were performed before immunocytochemistry. CAE reactivity could be demonstrated either before or after immunocytochemistry. Cell surface antigens could be demonstrated with most immunocytochemical methods: however, the APAAP method was preferred for its sensitivity and effectiveness when combined with enzyme cytochemistry. By this approach, cells expressing only immunologic markers and cells expressing only cytochemical markers could easily be distinguished from those coexpressing both markers, because cytochemistry and immunocytochemistry could be combined without affecting the reactivity of each marker, and the reaction products did not hamper the interpretation of preparations.

Antigens, Surface↗

Monocytoid B-cell lymphoma with bone marrow and peripheral blood involvement at presentation.

A case of malignant lymphoma showing in a lymph node the characteristic morphologic features of the so-called monocytoid B-cell lymphoma (MBCL) is described. This case differs from the reported cases in the literature because atypical cells were observed in the bone marrow biopsy and marrow and peripheral blood smears that were obtained from the patient, a 61-year-old man, during the staging procedures. Lymphocyte surface marker studies on peripheral blood by flow cytometry and DNA analysis revealed a monoclonal population of lambda-positive lymphocytes. The immunophenotype of MBCL cells was studied both in paraffin-embedded lymph node sections by immunoperoxidase method and in peripheral blood by flow cytometric analysis; the cells expressed the SIg with lambda light chain restriction and the HLA-DR antigen; they also had positive results for B-cell-associated antigens, including LN1, LN2, CD 20, CD 22, CD 19, CD 9 but not CD 21, CD 24, and CD 10, T-cell-associated antigens and monocytic markers. In addition, they had negative results for CD 25, CD 38, PCA-1. This report emphasizes that in MBCL, peripheral and marrow involvement may occur at presentation analogous to other low-grade B-cell lymphomas. The immunophenotypic characteristics of MBCL cells, though not pathognomonic, are considered to be helpful in differentiating them from circulating cells of other B-cell lymphomas.

Antigens, Differentiation, B-Lymphocyte↗

Expression of Leu-8 surface antigen in B-cell lymphomas. Correlation with other B-cell markers.

Using in situ immunohistological analysis, expression of Leu-8 and its correlation with other B-cell markers were investigated in 21 selected lymphomas of different categories, each one expressing its own typical immunophenotype. These categories included eight follicular centroblastic/centrocytic (CB/CC) lymphomas, eight intermediately differentiated lymphocytic lymphomas (ILL)/mantle zone lymphomas (MZL), and five lymphocytic lymphomas (LL) associated with chronic lymphocytic leukaemia (CLL). Four reactive lymph nodes and three tonsils were also studied using double immunolabelling procedures. Cell suspensions were also performed in three CB/CC and four ILL/MZL cases. Leu-8 was consistently expressed in ILL/MZL and LL but it was absent in most (7/8) CB/CC lymphomas. In reactive tissues, the Leu-8-positive B cells were strictly confined to the mantle zones. A close association emerged between Leu-1 (CD5) and Leu-8, both being present in ILL/MZL and LL but absent in CB/CC. A consistent lack of association was found between Leu-8 or CD5 antigens and common acute lymphoblastic leukaemia antigen (CD10) and BA-2 (CD9) antigen, whereas Leu-8 and CD5 were strictly associated with surface IgD. Reactivity with Leu-8 provides a means of distinguishing between CB/CC and ILL/MZL. Furthermore, shared immunoreactivity for Leu-8 in ILL/MZL and LL may represent a potential clue to the still uncertain cellular derivation of LL/B-CLL.

Antigens, Differentiation, T-Lymphocyte↗

Heterogeneous in situ immunophenotyping of follicular dendritic reticulum cells in malignant lymphomas of B-cell origin.

The phenotype of follicular dendritic reticulum cells (DRC) was analyzed with monoclonal antibodies (DRC-1, OKB7, BA-2, Leu-M3, and antidesmoplakin 1 and 2) in 28 frozen biopsy specimens of both morphologically and phenotypically analyzed B-cell lymphomas and 21 normal or reactive controls. The former included 15 follicular center cell lymphomas (FCCL), four intermediately differentiated lymphocytic lymphomas (ILL), four mantle zone lymphomas (MZL), and five well-differentiated lymphocytic lymphomas (WDLL). In controls, DRC-1+ and OKB7+ DRC were localized in both follicular centers (FC) and mantle zones (MZ), but BA-2+ and Leu-M3+ DRC were confined to FC only. FCCL were usually accompanied by DRC-1+, OKB7+, and BA-2+ DRC, and either lost or maintained positively with Leu-M3 from case to case. By contrast, MZL consistently lacked BA-2+ and Leu-M3+ DRC, and was associated with DRC-1+ and OKB7+ DRC only. Desmoplakin-positive DRC occurred in variable proportions in both FCCL and MZL. As opposed to FCCL and MZL, all WDLL and all but one of the ILL (associated only with DRC-1+, OKB7+, and desmoplakin+ DRC) did not show any DRC as identifiable with the antibody panel used. Remarkably, the difference in the distribution of BA-2+ and Leu-M3+ DRC in the normal FC and MZ appears to be maintained in their neoplastic counterparts (FCCL and MZL) also. Such a difference represents an example of the possible interactions between lymphoma cells of different phenotype and their microenvironment, as portrayed by phenotypically heterogeneous DRC.

Antibodies, Monoclonal↗

The relevance of VDJ PCR protocols in detecting B-cell clonal expansion in lymphomas and other lymphoproliferative disorders.

AIMS AND BACKGROUND: The detection of immunoglobulin heavy chain variable (VH)-diversity (DH)-joining (JH) region gene rearrangement by polymerase chain reaction (VDJ PCR) has been recently proposed as a rapid approach to assess B-cell clonality in lymphoproliferative disorders. The aim of the present study was to determine the efficacy of VDJ PCR in a wide spectrum of lymphoproliferative disorders previously characterized by immunohistochemistry and Southern blot (SB). METHODS: 83 SB-rearranged B-cell non-Hodgkin's lymphomas (NHL) of different histotype, 22 cases of SB-unrearranged classical Hodgkin's disease (HD), 18 cases of HIV-related reactive lymphadenopathy, and 4 frankly pre-lymphomatous lesions (MESA) in the course of Sjögren's syndrome were investigated by 2 different VDJ PCR protocols (FR3, FR2). RESULTS: The detection rate in NHL was 64% and 71% using the protocols FR3 and FR2, respectively. However, the overall VDJ PCR efficacy increased to 81% by combining the results of both protocols. In addition, differences in the combined, as well as in the single FR3 or FR2 protocol efficacy, were noted in the different NHL subgroups. B-cell clonality was also detected in 4/22 (18%) SB-unrearranged classical HD cases and in 2/18 (11%) reactive lymphadenopathy cases, whereas it was demonstrated in all the MESA lesions, 2 of them being SB-negative. CONCLUSIONS: VDJ PCR represents a useful and rapid technique to detect B-cell clonality in NHL, although with some differences depending on the NHL histotype and the panel of primers employed. The technique may also be of value to investigate the possible progression of early B-cell clonal expansion into frankly B-cell malignancy and to contribute to the controversy about the clonal lineage origin of the putative HD malignant cells.

AIDS-Related Complex↗

Methods of simultaneous visualization of cytoplasmic enzyme reactivity and cell surface antigens (by cytochemistry combined with immunocytochemistry) in individual hematopoietic and lymphoid cells.

Enzyme cytochemistry alone, and more recently, immunocytohistochemistry have been satisfactorily used by hematologists and hematopathologists for the study, diagnosis and classification of human hematological and lymphoproliferative disorders. To enhance the potential of these techniques, the possibility of combining immunocytohistochemical techniques with enzyme cytohistochemistry with simultaneous visualization of both reaction products has been examined by some investigators. This approach has been applied to normal, reactive and neoplastic material using mainly cell suspensions and frozen sections, with the aim of improving cell identification in specimens containing different cell types, of determining the cytochemical profiles of well-defined lymphocyte subpopulations and of establishing the cell surface phenotypes of cells that are positive for certain enzymes. In this paper, published reports on this subject are reviewed and compared with the experience of our study group.

B-Lymphocytes↗

Can Reed-Sternberg cells of classic Hodgkin's disease be considered B-cells?

During the last twenty years, the issue of the nature of Reed-Sternberg (RS) cells of Hodgkin's disease (HD) has been addressed by multiple methodological approaches. In recent times, a major insight into HD has been obtained through molecular studies of isolated cells which have proven the clonal nature of HD. In parallel to molecular investigations some novel biologic markers specifically associated with the different stages of mature B-cells have helped to define the cellular origin of HD. This review deals with histological features of HD and summarizes recent results from molecular and immunohistochemical studies focusing on the origin and the stage of differentiation of RS cells.

B-Lymphocytes↗