Practical value of genotypic analysis for diagnosing lymphoproliferative disorders.

The value of DNA hybridisation (using immunoglobulin and T cell receptor gene probes) was assessed during the diagnosis of problematical lymphoid tissue biopsy specimens. In 14 of 18 specimens (78%), which contained a malignant lymphoproliferation of uncertain aetiology, this technique permitted the demonstration of a monoclonal proliferation of B cells (nine cases) or T cells (five cases). In five further lymph node biopsy specimens, in which the differential diagnosis lay between a reactive or malignant process, a clonal proliferation was shown in three cases.

Keratin immunohistochemistry in normal human liver. Cytokeratin pattern of hepatocytes, bile ducts and acinar gradient.

A panel of 2 polyclonal and 7 monoclonal antibodies directed against cytokeratins was tested on cryostat and paraffin sections of 14 normal human liver biopsies using an immunoperoxidase procedure. The staining characteristics of hepatocytes and bile ducts are reported. On cryostat sections, monoclonal antibodies directed against individual cytokeratins no.

Immunohistochemical study of epidermal Langerhans cells and dermal dendritic cells in benign and malignant skin lesions characterized by a dermal lymphoid infiltrate consisting either of B-cells or T-cells.

Skin biopsies from 43 patients with a rather dense dermal lymphoid infiltrate of either inflammatory or neoplastic nature have been investigated. We studied the number, distribution and immunophenotype of epidermal Langerhans cells and dermal dendritic cells. As previously reported, differences in epidermal Langerhans cell and dermal dendritic cell numbers between skin biopsies with a B-cell infiltrate and skin biopsies with a T-cell infiltrate were found, dendritic cells being more numerous in the latter.

In situ characterisation of the (peri)portal inflammatory infiltrate in acute hepatitis A.

The portal and acinar zone 1 (periportal) inflammatory infiltrate in acute hepatitis A (HA) strongly resembles piecemeal necrosis (PMN) in chronic hepatitis B (HB). The latter infiltrate has been characterized in detail previously, and a predominance of suppressor/cytotoxic T cells has been demonstrated. For comparison we analyzed the infiltrate in acute HA in three liver biopsies, applying a broad panel of monospecific and monoclonal antibodies.

Mantle zone lymphoma. Immuno- and enzymehistochemical studies on the cell of origin.

Using in-situ immuno- and enzymehistochemical techniques, the phenotype of the neoplastic cells in seven cases of mantle zone lymphoma (MZL) was compared to that in seven cases of nodular poorly-differentiated lymphocytic lymphoma (NPDLL). The neoplastic nodules in MZL consisted of medium-sized lymphoid cells with slightly irregular nuclei and finely dispersed chromatin, expressing monoclonal surface IgM or IgM plus IgD, and displaying membranous alkaline phosphatase (ALP) activity. These cells proliferated around follicular centers that demonstrated a polyclonal pattern of reactivity for both types of light chains and a distorted meshwork of dendritic reticulum cells.

The marginal zone in the human reactive lymph node.

The presence and localization of the marginal zone (MZ) in the human lymph node is controversial. The authors analyzed the distribution of sIgM+sIgD- MZ lymphocytes (MZL) expressing alkaline phosphatase (ALP) activity in a series of reactive lymph nodes and spleens with the use of immuno- and enzymehistochemistry, and a combination of both technics. MZL were found scattered in lymphocytic coronas composed of densely packed, small, round lymphocytes.

The histological characterization of ALIP in the myelodysplastic syndromes.

Bone marrow biopsies of patients with a myelodysplastic syndrome (MDS) may, in the absence of an increased number of blasts in the bone marrow smears, contain small clusters of immature precursors. The presence of these cell nests, previously described as "abnormal localized immature precursors" or ALIP, bears a strong prognostic value predisposing patients to early death with an increased risk to develop myeloid leukaemia. In order to describe and delineate this histological characteristic more precisely, we compared bone biopsies of patients with MDS, used in these previous studies, with bone marrow biopsies performed for staging procedures in patients with Hodgkin's disease, non-Hodgkin's lymphoma and carcinoma.

Sarcoma arising from interdigitating reticulum cells: report of a case, studied with light and electron microscopy, and enzyme- and immunohistochemistry.

The morphological, enzyme- and immunohistochemical features of a sarcoma arising from interdigitating reticulum cells (IDRC) are presented. These cells are normal constituents of the T-dependent region of lymphoid organs, and their function is largely unresolved. The immunohistochemical findings in the present case indicate that neoplastic IDRC are morphologically and phenotypically similar to normal IDRC in lymphoid organs.

Expression of HLA-DR and T6 antigens on keratinocytes and dendritic cells. A comparative immunohistochemical study.

The number, morphology, and distribution of cells with dendritic processes in the epidermis and dermis, as well as the expression of HLA-DR and T6 antigen on keratinocytes in 66 skin biopsy specimens have been studied. In the epidermis, OKT6+ cells with slender dendritic processes predominated in the upper layers and outnumbered OKIa1+ cells with dendritic processes, which were only fragmentarily stained and present throughout all layers. In the dermis, OKIa1+ cells with dendritic processes outnumbered OKT6+ cells with dendritic processes.

Merkel cell tumor of the skin: an immunohistochemical study.

Skin biopsy specimens from 12 elderly patients with Merkel cell tumors were investigated. Conventional light microscopy and immunohistochemical techniques were used. All of the tumors had similar morphologic features.

New sites of human S-100 immunoreactivity detected with monoclonal antibodies.

In a previous paper from this laboratory, the production of monoclonal antibodies recognizing antigenic determinants common to the alpha and beta chains of bovine brain S-100 protein was reported. In the present study, the immunohistochemical labeling patterns of these monoclonal antibodies against a wide range of normal and pathologic human tissues are described, and these results are compared with those obtained using polyclonal anti-S-100 antiserum. Although many of the reactions of the monoclonal antibodies were very similar to those of the polyclonal antiserum (and the previously reported sites of S-100 immunoreactivity) several additional cell types (e.

Immunoelectron microscopic investigation of HLA-DR-positive dendritic cells at the dermo-epidermal junction in skin disorders associated with the deposition of immune complexes.

HLA-DR-positive dendritic cells present at the dermo-epidermal junction in skin disorders associated with the deposition of immunoglobulins and/or complement factors in the skin biopsy are investigated ultrastructurally. They demonstrate long, slender cytoplasmic processes, an indented nucleus, and strikingly dilated cisternae of the endoplasmic reticulum. HLA-DR antigen is present on the plasma membrane and within some of the dilated cisternae.

The cellular composition of granulomas in mesenteric lymph nodes from patients with Crohn's disease.

The immunohistochemical findings in granulomatous lymphadenitis in patients with Crohn's disease are presented and compared with conventional light microscopic findings. The cellular composition of the granulomas in mesenteric lymph nodes was examined with a broad panel of monoclonal and polyclonal antibodies directed to B-cells, T-cells, monocytes/macrophages, dendritic reticulum cells, HLA-DR antigens and the transferrin receptor. The centre of the granulomas contains OKIa+, OKM1+, OKT9+, DRC-, To5- epithelioid cells and giant cells and OKT3+ lymphocytes.

The composite nodule. A structural and functional unit of the reactive human lymph node.

The relationship between T nodules and adjacent B-lymphoid follicles was investigated in 37 reactive lymph nodes by light microscopy and combined enzyme immunohistochemistry. In 16 cases (43%), T nodules and adjacent B-lymphoid follicles were unified in an ovoid, distinct nodular structure termed a "composite nodule." The composite nodule comprises two separate domains.

Ultrastructural immunocytochemical demonstration of HLA class I antigens in human pathological liver tissue.

Major histocompatibility complex products Class I (HLA Class I) antigens are not expressed on the surface of normal human hepatocytes but become so in pathological conditions. The purpose of this study was to specify the ultrastructural topography of HLA Class I antigens expression. Nine human liver specimens, known from light microscopic investigation to display membranous positivity for HLA Class I antigens, were processed for immunoelectronmicroscopy using monoclonal anti-HLA Class I in an indirect immunoperoxidase procedure.

Cellular composition of suppurative granulomas: an immunohistochemical study of suppurative granulomatous lymphadenitis.

The immunohistochemical findings from an investigation of suppurative granulomatous lymphadenitis (SGL) are presented. With a broad panel of monoclonal and polyclonal antibodies directed against B cells, T cells, monocytes/macrophages, HLA-DR antigens, and the transferrin receptor, early, nonsuppurative granulomas were found to consist of OKM1+ OKIa1+ OKT9+ epithelioid histiocytes and multinucleated giant cells, admixed with variable numbers of OKT4+ Leu-3a+ helper/inducer T cells. These nonsuppurative lesions were surrounded by distinctive cuffs of BA1+ B1+ sIgM+ sIgD+ OKIa1+ lymphocytes.

A recommended procedure for ultrastructural immunohistochemistry on small human tissue samples.

Various fixation and staining procedures for the demonstration of surface and cytoplasmic antigens have been described. An immunostaining procedure was sought that would allow the demonstration of these antigens, especially in small human tissue samples at the ultrastructural level. A modification and adaptation of the technique of Eldred, Zucker, Karten, and Yazula (J Histochem Cytochem 31:285, 1983) was applied on several varieties of human tissue, including liver, skin, and lymphoid tissue, using monoclonal and polyclonal antibodies in an indirect peroxidase procedure.

A case of histiocytosis X-central type. Histological, immunohistochemical and electronmicroscopical analysis.

We report a case of Histiocytosis X (HX) associated with a high bone marrow and peripheral blood monocytosis in a 70 yr-old man. The histiocytic clusters in the skin showed the characteristics of epidermal Langerhans cells (LC): positivity for OKT6, OKIa1, ATP-ase and presence of Birbeck granules. Histiocytes in all other locations showed positivity for OKM1, OKIa1, acid P-ase and absence of Birbeck granules.

Nodular alteration of the paracortical area. An in situ immunohistochemical analysis of primary, secondary, and tertiary T-nodules.

With the use of in situ immunohistochemical techniques on freshly frozen and paraffin-embedded material from 63 reactive lymph nodes, the cellular composition of T-nodules observed in 30 cases with nodular alteration of the paracortical area was analyzed. T-nodules were composed of S-100 beta + interdigitating reticulum cells (IDRCs), variable numbers of OKT6+ dendritic cells (DCs), high endothelial venules, and a very high T helper/T suppressor ratio because of an enrichment of OKT4+, Leu3a+ helper/inducer T cells in these nodules. According to their localization in the paracortical area, and the arrangement of IDRCs and high endothelial venules, T-nodules could be divided into "primary" and "secondary" T nodules.

Reproducibility and prognostic value of different non-Hodgkin's lymphoma classifications: study based on the clinicopathologic relations found in the EORTC trial (20751).

In the EORTC trial 20751, six pathologists belonging to five different centers classified tumoral lymph nodes from 406 untreated patients with non-Hodgkin's lymphoma (NHL) into three different NHL classifications. NHL were most easily and reliably subdivided according to the growth pattern (the rate of consensus being 93%). Classification according to growth pattern proved to be of prognostic significance.

Prognostic factors in the myelodysplastic syndromes: importance of initial data on peripheral blood counts, bone marrow cytology, trephine biopsy and chromosomal analysis.

An analysis of clinical, haematological, histological and cytogenetic data was performed in 85 consecutive patients with myelodysplastic syndromes (MDS). The criteria for diagnosis of refractory anaemia (RA), acquired idiopathic sideroblastic anaemia (AISA) and chronic myelomonocytic leukaemia (CMML) were clearly defined, since the inclusion criteria provided by the FAB co-operative group are imprecise. None of these patients has received chemotherapy during the follow-up period.