Immunoreactivity of neoplastic and non-neoplastic monocytoid B lymphocytes for DBA.44 and other antibodies

AIMS--To evaluate the immunoreactivities of neoplastic and non-neoplastic monocytoid B cells (MBC) and compare them with hairy cell leukemia (HCL) and mantle cell lymphoma (MCL). METHODS--An immunohistochemical study of paraffin wax embedded sections was done on surgically resected specimens of spleens with MBC clusters from patients with gastric cancer (14 cases), tonsils (five cases), and lymph node (two cases) showing lymphoid follicular hyperplasia (LFH), submandibular lymph nodes containing MBC in Sj?gren's syndrome (one case). Extranodal organs affected by MCL (three cases) and monocytoid B cell lymphoma (MBCL) (seven cases), and spleens from HCL (four cases) were also studied. These specimens were fixed in 10% formalin and routinely processed for paraffin wax embedding. Fresh spleen specimens from patients with liver cirrhosis (one case) and gastric cancer (seven cases) were snap frozen. RESULTS--Mantle zone lymphocytes were DBA.44, CD74 positive and showed a weaker reaction for CDw75 than marginal zone lymphocytes and MBC, which were almost DBA negative. In neoplastic diseases tumour cells in MCL were DBA.44, CD74, and CDw75 positive. MBCL showed a positive reaction for CD74 and CDw75, but positivity for DBA.44 was observed in only one of seven cases. The HCL specimens, all positive for DBA.44, showed a weaker reaction for CD74 and a stronger reaction for CDw75 than either MCL and MBCL specimens. CONCLUSION--These results show that mantle zone lymphocytes and MCL more closely matched HCL for reactivity to DBA.44 than MBC and MBCL. Reactivities for DBA.44 and CDw75 were greater in MBCL compared with its non-neoplastic counterpart, MBC.     

BCL-2 immunohistochemical evaluation in B-cell chronic lymphocytic leukemia and hairy cell leukemia before treatment with fludarabine and 2-chloro-deoxy-adenosine

Bcl-2 overexpression has been shown to be associated with several malignancies, including B-cell chronic lymphocytic leukemia (CLL) and non-Hodgkin's lymphomas (NHL), mainly low-grade and follicular in type. It has as yet not been described in hairy cell leukemia (HCL). In 30 patients with CLL and 14 with HCL who were consecutively selected for treatment with purine analogues (Fludarabine in CLL and 2-chloro-deoxy-adenosine in HCL), we evaluated bcl-2 oncoprotein expression in leukemic cells on marrow sections that were taken before treatment and stained immunohistochemically with a monoclonal antibody (Dakopatts 124 clone), by the avidin-biotin-peroxidase method. All samples were found to be bcl-2 positive, with a staining intensity that was moderate to strong in CLL and weak to moderate in HCL. 83% of CLL and 100% of HCL patients were responsive to purine analogues. These findings show that bcl-2 is overexpressed in almost all cases CLL and HCL and that bcl-2 overexpression does not predict a poor response to purine analogues, which are believed to induce apoptosis.     

Phenoloxidase-dependent cytotoxic mechanism in ascidian (Styela plicata) hemocytes active against erythrocytes and K562 tumor cells

The distinction between mantle cell lymphoma (MCL) and other low-grade B-cell neoplasms is important because MCL has a more aggressive clinical course. In bone marrow biopsy specimens, this distinction can be especially difficult. We examined 70 bone marrow biopsy specimens involved by various B-cell lymphoid neoplasms to assess the utility of cyclin D1 immunostaining in distinguishing MCL from other B-cell lymphoproliferative disorders. We used a cocktail of two monoclonal anti-cyclin D1 antibodies and a heat- and sonication-induced epitope retrieval procedure. The neoplasms assessed included MCL (32 cases), small lymphocytic lymphoma/chronic lymphocytic leukemia (18 cases), follicular lymphoma (11 cases), hairy cell leukemia (5 cases), splenic marginal zone lymphoma (2 cases), and small lymphocytic lymphoma with plasmacytoid differentiation (2 cases). The diagnosis of MCL in bone marrow was confirmed by review of the original diagnostic biopsy specimens along with additional data, such as immunophenotypic or molecular studies. Most MCL (23/32; 72%) cases expressed cyclin D1 protein. In contrast, one case of small lymphocytic lymphoma/chronic lymphocytic leukemia (1/18; 6%) and one case of hairy cell leukemia (1/5; 20%) expressed cyclin D1 protein. These findings demonstrate that immunostaining for cyclin D1 protein expression is useful in distinguishing MCL from other B-cell lymphoid neoplasms in the bone marrow.     

Hairy cell leukemia: a histo-cytochemical and ultra-structural study

We studied five patients with hairy cell leukemia (HCL) diagnosed within the last ten years at the Department of Hematology of Universidade Federal de S?o Paulo-Escola Paulista de Medicina. Our purpose was to analyze the value of transmission electron microscopy (TEM) by comparing this method with the conventional ones. At diagnosis, patients presented weight loss, spleen enlargement and hairy cells (HC) in peripheral blood and bone marrow slides. HC was characterized by morphology and tartrate test resistance in the acid phosphatase reaction (TRAP). At the evaluation time, the amount of HC ranged from 1% to 85% of WBC count. All patients, except two, had phenotype B. In these last two, TRAP as well as phenotype B could not be documented due to low HC numbers in their exams. Cytoplasmatic projections and the absence of lamellar ribosomic complex were the most frequent ultrastructural findings, even in those patients with the lowest HC numbers. Based on these features, TEM is an efficient method for searching for HC at HCL diagnosis and during the course of the disease.     

Peripheral antihyperalgesic effect of morphine to heat, but not mechanical, stimulation in healthy volunteers after ultraviolet-B irradiation

We tested a total of 174 paraffin-embedded hematolymphoid neoplasias to determine whether CD10 can be specifically and sensitivity detected on paraffin sections using monoclonal antibody 56C6 after epitope retrieval. For 32 cases, results of CD10 detection by immunohistochemistry were compared with flow cytometric data. In only 1 case of follicle center lymphoma, divergent staining results were found with the detection of CD10 by flow cytometry but not by immunohistochemistry. Altogether, 22 of 28 follicle center lymphomas, 2 of 6 hairy cell leukemias, 14 of 34 diffuse large B-cell lymphomas, 3 of 3 Burkitt lymphomas, 4 of 5 precursor B-lineage acute lymphoblastic leukemias, and 2 of 4 T-lymphoblastic lymphomas were CD10+. Decalcification of bone marrow biopsy specimens did not diminish the staining intensity. All other cases, including 10 acute myeloid leukemias and a range of low-grade B-cell lymphomas, were CD10-. CD10 is reliably detectable with antibody 56C6 on paraffin sections using epitope retrieval. The antibody is especially useful for the subclassification of acute leukemias and low-grade B-cell lymphomas.     

Improved detection of CD5 epitope in formalin-fixed paraffin-embedded sections of benign and neoplastic lymphoid tissues by using biotinylated tyramine enhancement after antigen retrieval

To evaluate the effectiveness of the immunohistochemical staining of B- and T-cell lymphomas with Leu-1 (clone L17F12 CD5 antibody, Becton Dickinson, San Jose, Calif) in formalin-fixed paraffin-embedded sections, we stained 12 specimens reflecting cases of chronic lymphocytic leukemia/small lymphocytic lymphoma, 7 of mantle cell lymphoma, 13 of T-cell lymphomas, and 9 of various B-cell neoplasms that do not ordinarily express CD5, using a streptavidin-horseradish peroxidase method with biotinylated tyramine enhancement after antigen retrieval. We were able to detect CD5 reactivity of neoplastic cells in 9 (75%) of 12 cases of chronic lymphocytic leukemia, 6 (86%) of 7 cases of mantle cell lymphoma, and 13 (100%) of 13 of the T-cell lymphomas. B-cell neoplasms (9/9) not typically associated with CD5 expression showed no reactivity of tumor cells. We conclude that the Leu-1 (CD5) antibody, routinely used for cryopreserved tissues, is also effective in formalin-fixed paraffin-embedded sections using an antigen retrieval and streptavidin-horseradish peroxidase method with biotinylated tyramine.     

Occult B cell malignancies can be detected by three-color flow cytometry in patients with cytopenias

Patients with unexplained cytopenias often present a diagnostic dilemma with minimal morphologic or cytogenetic changes to identify the underlying disease process. We have used multidimensional flow cytometry in a study of patients with cytopenias and found that this technology established, changed, or refined the diagnosis in 17/121 patients. Using the flow cytometric technique of CD45 and right angle light scatter (SSC) gating with two additional markers in a three-color analysis, eight of 121 patients were found to have hairy cell leukemia (HCL), in the absence of definitive morphologic findings of HCL. Two additional patients were found to have non-Hodgkin's lymphoma (NHL). Myeloid abnormalities, myelodysplasia (MDS) or acute leukemia was detected in seven of 56 patients with unexplained pancytopenia. Six of 65 patients identified with cytopenias resulting from lymphoid neoplasms had been referred for bone marrow transplantation (BMT) with a presumptive diagnosis of MDS, with subsequent deferral of BMT upon correct diagnosis. The screening technique is incorporated into an extensive immunophenotyping scheme to identify hematopoietic abnormalities using multidimensional flow cytometry (MDF). HCL cells (detected as low as 1.3%) reside in the same position as normal monocytes in the CD45 and SSC plots but could be distinguished from monocytes based on the expression of HLA-DR without CD11b, and expression of CD19. Further phenotyping of the abnormal population confirmed immunoglobulin light chain restriction, CD11c, and CD25 expression. Non-Hodgkin's lymphoma was detected as aberrant mature lymphocytes expressing B lymphoid markers, CD5 and light chain restriction. Myeloid abnormalities were identified in the myeloblast or maturing myeloid cell fractions. The flow cytometric scheme described can be used in primary diagnosis. The technique is definitive, sensitive, and stresses the importance of distinguishing lymphoid from myeloid etiology of cytopenias.     

Relationship between symptoms of jumper''s knee and the ultrasound characteristics of the patellar tendon among high level male volleyball players

In this study we investigated the applicability of 99mTc-labeled CD19 monoclonal antibody (mAb) for tumor imaging in patients with B cell non-Hodgkin's lymphoma. A 1-mg sample of murine CD19 mAb was labeled with approximately 550 MBq [99mTc]pertechnetate. The labeled mAb was administered i.v. to seven patients, four without and three with pretreatment with 10 mg unlabeled CD19 mAb. The number of circulating B cells was decreased by 44 +/- 5% 1 h after injection of the radiolabeled mAb. Peripheral B cells were coated with CD19, resulting in partial modulation of CD19, most pronounced in the three pretreated patients. Whole-body images were obtained with a gamma camera and compared with results obtained by conventional imaging techniques. Initially, blood-pool activity dominated, whereas 24 h after injection the radioactivity was mainly located in the spleen, kidneys and liver. In two patients, a lesion in the spleen appeared as an unlabeled spot. In one patient, a lesion in the femur, which was detected by computed tomography (CT) and gallium-67 scans, was also seen on the CD19 scan from 1 h after administration of the radioimmunoconjugate onwards. Good imaging of bone marrow infiltration was observed in one of three patients. Lymph node involvement was not observed in any of the patients in whom affected lymph nodes were detected by CT or gallium-67 scan. In conclusion, in the present study radioimmunodetection with 99mTc-labeled CD19 mAb was found to be inferior to CT and gallium-67 scanning in the diagnosis of patients with B cell non-Hodgkin's lymphoma.     

Leukemic phase of mantle cell lymphoma presenting as anemia: diagnosis by combining flow cytometry and cytomorphology

We report a case of mantle cell lymphoma in leukemic phase, which was diagnosed by a bone marrow biopsy performed as part of a workup for chronic anemia in a patient without lymphadenopathy. The patient, a 79-year-old man with diabetes mellitus, hypertension, chronic renal failure, congestive heart failure, and atherosclerosis, presented with claudication. On admission, he also had an 8-month history of anemia, during which time he experienced a 18-kg weight loss. On presentation, the patient had normal vital signs, anemia, leukocytosis (as well as an absolute lymphocytosis), and splenomegaly; as mentioned, lymphadenopathy was absent. A bone marrow biopsy showed an increase in small to intermediate-sized, slightly irregular lymphocytes in interstitial nodules. Flow cytometric immunophenotyping of the bone marrow identified a monoclonal population of cells, representing 25% of cells within the bone marrow, with expression of CD19, CD20, immunoglobulin M/D, lambda light chain, HLA-DR, and CD5; reactions for CD10 and CD23 were absent. Based on morphologic and immunophenotypic analysis of the bone marrow, as well as morphologic review of the peripheral blood smear, a diagnosis of mantle cell lymphoma involving the bone marrow and in leukemic phase was made. Subsequent polymerase chain reaction analysis of DNA from peripheral blood identified a population of cells with the bcl-1 rearrangement. This case is unique in that the diagnosis of mantle cell lymphoma was made without lymph node or spleen analysis and the patient, although exhibiting bone marrow and peripheral blood involvement by mantle cell lymphoma at presentation, did not have lymphadenopathy.     

Detection of Epstein-Barr virus in transformations of low-grade B-cell lymphomas after fludarabine treatment

Fludarabine is a highly effective chemotherapeutic agent for chronic lymphocytic leukemia/small lymphocytic lymphoma and is also active in other B-cell lymphoproliferative disorders. Although highly efficacious in destroying the malignant B-cells, fludarabine also causes T-cell lymphopenia and immunosuppression. We present five patients given fludarabine for low-grade B-cell lymphoproliferative disorders who showed transformation of the primary neoplasm to a higher grade tumor. Immunohistologic antibody studies were performed on paraffin-embedded tissue sections of the initial tissue (when available) and on the follow-up biopsy specimens for CD20, CD3, CD45RO, CD43, CD30, CD15, and latent membrane protein (LMP-1) for Epstein-Barr virus (EBV). The initial diagnoses in these five patients included chronic lymphocytic leukemia/small lymphocytic lymphoma (three cases), follicle center lymphoma (one case), and Waldenstrom's macroglobulinemia (one case). All of the follow-up biopsy specimens showed scattered Hodgkin's-like cells, and two of the five also showed foci of large-cell transformation. The Hodgkin's-like cells showed CD30 immunoreactivity in four of the five cases and CD15 immunoreactivity in three of the five. Strong immunoreactivity of the large, atypical, Hodgkin's-like cells for LMP-1 of EBV was noted in four cases; in the remaining case, this finding was equivocal. In situ hybridization for EBV-encoded RNA was positive in four of the five cases. Molecular studies by polymerase chain reaction (PCR) showed the presence of EBV in three of the five cases. PCR for detection of immunoglobulin heavy chain demonstrated identical monoclonal rearrangements in the original lymphoma and transformation in one case with available material. The CD4 lymphocyte count in each patient was less than 550/microL, indicating cellular dysfunction. Transformation of low-grade non-Hodgkin's lymphomas after fludarabine therapy might be associated with EBV and severe immunosuppression.     

Neoplastic human tissue mast cells express the adhesion molecule CD44/HCAM

Expression of the homing-associated cell adhesion molecule/HCAM (CD44) in normal/reactive and neoplastic human tissue mast cells (TMC) was determined immunohistochemically using the antibody DAKO-DF1485, which detects all isoforms of CD44. Studies were performed on 30 routinely processed specimens. Twenty of these, from bone marrow, skin, spleen, liver, lymph node and jejunal mucosa, contained infiltrates of TMC. These represented various types of generalized mastocytosis/systemic mast cell disease, including benign systemic mastocytosis. Ten specimens consisted of tissue with a marked reactive increase in TMC; most of these were lymph nodes with chronic nonspecific lymphadenitis and benign or malignant solid tumours. In all 30 specimens TMC exhibited an annular pattern of immunostaining, which was usually very strong. Both normal/reactive and neoplastic TMC exhibited consistent immunoreactivity with the antibody DAKO-DF1485, and this antibody may be of diagnostic value in the detection of atypical TMC associated with malignant mastocytosis. TMC and their neoplastic derivatives belong to a large family of mesenchymal and epithelial cells containing the principal surface receptor for hyaluronan.     

Expression of CD44 (HCAM) in small lymphocytic and mantle cell lymphoma

Small lymphocytic lymphoma (SLL) and mantle cell lymphoma (MCL) are small B-cell lymphomas that share many morphological and immunophenotypic features, both expressing the T-cell antigen CD5. Because of this, there is speculation that these two lymphomas may have a common origin, both arising from the mantle zone of the lymph node. CD44 (HCAM), a glycoprotein "homing receptor," has been reported as a marker of small B-cell lymphomas for determining behavior as well as the nodal cell of origin. Intensity of CD44 expression also has been correlated with dissemination of lymphoma. We studied 50 cases with classic features of SLL (30 cases) or MCL (20 cases). Immunophenotypic analysis was performed on paraffin sections. All cases of MCL and SLL were CD20 positive; CD5 was expressed in 19 of 25 (76%) SLL and 11 of 15 (73%) MCL. Cyclin D1 was expressed in 11 of 17 (76%) MCL and no cases of SLL. CD43 coexpression was seen in 27 of 29 (93%) SLL and 17 of 19 (89%) MCL. CD23 was positive in 25 of 28 (89%) SLL and 2 of 20 (10%) MCL. Bcl-2 was positive in 18 of 22 (82%) SLL and 15 of 16 (94%) MCL. CD44 was positive with moderate to strong intensity in 11 of 30 SLL and 15 of 20 MCL. Peripheral blood involvement did not correlate with CD44 immunoreactivity. MCL tended to have intense CD44 immunoreactivity, whereas SLL tended to show weaker CD44 intensity. This trend in the intensity of CD44 in MCL suggests that CD44 may be helpful in distinguishing SLL from MCL and possibly elucidating the origin of these CD5-positive B-cell neoplasms.     

Malignant histiocytosis-like B-cell lymphoma, a distinct pathologic variant of intravascular lymphomatosis: a report of five cases and review of the literature

Malignant histiocytosis (MH)-like B-cell lymphoma (BCL) is a neoplastic proliferation of large B cells clinically characterized by fever, hepatosplenomegaly, haemophagocytosis and abnormal laboratory data, without lymphadenopathy or skin lesions. Interestingly, most cases have been reported in Asian patients, and it is unclear whether MH-like BCL is biologically distinct from conventional large B-cell lymphomas. We report five Japanese patients with MH-like BCL. Biopsied specimens of bone marrow, liver and/or spleen showed infiltration of neoplastic B cells accompanied by haemophagocytosing histiocytes. Lymphoma cells were positive for CD19, CD20 and HLA-DR surface antigens, and negative for CD5 and CD10. In four cases elevated serum levels of interleukin (IL)-6 and the soluble IL-2 receptor isoform were noted, but not IL-1beta, IL-2 or tumour necrosis factor-alpha. Autopsies of two cases were pathologically diagnosed as intravascular lymphomatosis (IVL). Based on these observations, the current and nine previous cases reported as MH-like BCL in Japan were re-evaluated. They appear to form a peculiar variant of IVL, characterized by bone marrow involvement at presentation, haemophagocytic syndrome, and a rapidly aggressive clinical course, but rarely neurological complications or skin lesions. This variant may merit separate consideration because of the problems posed in the initial diagnosis and therapeutic approaches.     

Detection of proliferative cells by DNA polymerase a as a proliferation associated marker]

Proliferative cell fractions were measured by flow cytometry in 20 patients with acute leukemia, 4 with chronic myelocytic leukemia in blastic crisis and 7 with malignant lymphoma. The cells were fixed with 2% paraformaldehyde followed by staining with fluorescein isothiocyanate conjugated monoclonal antibody against DNA polymerase a. The DNA polymerase a-positive population was widely distributed in leukemia, from 20.4% to 84.7% in peripheral blood and from 6.5% to 92.5% in the bone marrow. A positive correlation was found between the values in peripheral blood and bone marrow. The values ranged from 66.4% to 88.1% in cells from cases of malignant lymphoma. Cryopreserved cells may be available for measurement of DNA polymerase a because the result obtained in both frozen and fresh cells were essentially the same.     

Expression of CD44 variant v6 in breast carcinoma and its relationship with other parameters of tumor biology

BACKGROUND: The variant v6 of CD44 has been associated with metastatic behaviour in neoplasms such as lymphoma, colon carcinoma and breast carcinoma. The expression of CD44v6 in breast carcinoma by flow cytometry and its relationship with other tumor markers is studied in this paper. MATERIAL AND METHODS: The expression of CD44v6 was studied in 46 fresh tissue specimens by flow cytometry using a monoclonal antibody which recognizes the variant v6. Ploidy and cell cycle were also studied by flow-cytometry using propidium iodide labelling. p 53, c-erbB-2 and estrogen receptor expression as well as cell proliferation by Ki-67 staining were performed by immunohistochemistry. RESULTS: Nineteen out of 46 tumors were CD44v6 positive, without correlation with other tumor markers. Levels of CD44v6 in 19 positive samples sligtly correlates with S-phase and hystological grade. CONCLUSIONS: In the present study there was not a correlation among the presence of the variant v6 of CD44 on tumor cells from breast carcinoma and the aggressivity of the tumor. The expression of CD44v6 by flow cytometry does not seem to be a good prognostic marker.     

Identity in molecular structure between "differentiation enhancing factor" of murine erythroleukemia cells and the 30 kD heparin-binding protein of developing rat brain

Bone marrow involvement by anaplastic large cell anaplastic large cell (ALC) lymphoma can be difficult to detect on routine morphologic examination alone. In a series of 42 patients with ALC lymphoma, the authors analyzed: (1) the usefulness of a limited panel of monoclonal antibodies directed against CD30 (Ber-H2, HRS4) and epithelial marrow involvement on routinely processed biopsy specimens; and (2) the prognostic significance of bone marrow involvement as detected on both morphologic and immunohistochemical grounds. On conventional examination, 17% of the patients were found to have bone marrow involvement at diagnosis. However, after immunohistochemical analysis, occult malignant cells were detected in 23% of the patients with negative bone marrow biopsy on routine histology. The low percentage of positive cases on routine morphologic examination compared to immunohistochemical examination was related to: (1) the scarcity of neoplastic cells which were scattered among hematopoietic cells; (2) the difficulty of distinguishing malignant cells from immature hematopoietic elements; and (3) the absence of alteration of the reticulin network. The authors observed a significant association between marrow infiltration and the presence of hematologic abnormalities (mostly anemia or cytopenias) at diagnosis, both in children and adult patients. More importantly, a significant lower survival was seen in patients with bone marrow involvement compared to those without bone marrow involvement. Immunohistochemistry with anti-CD30 and anti-EMA antibodies should be performed systematically in bone marrow biopsies from patients with ALC lymphoma to reliably identify the presence of bone marrow involvement that appears to carry a poor prognosis.     

Increased splanchnic blood flow after hypoglycaemia in diabetic and normal man: evidence against glucagon as a mediator

Analysis of non-Hodgkin lymphoma (NHL) involvement of bone marrow trephine biopsy specimens by morphologic features and immunohistochemistry is often difficult, and the criteria for involvement are ill defined. We compared the morphologic and immunohistochemical analysis of B-cell NHL involvement with immunoglobulin heavy chain gene (IgH) rearrangement analysis by polymerase chain reaction (PCR) amplification of the complementarity determining region 3 (CDR3) in bone marrow biopsy specimens from patients with mantle cell lymphoma (n = 53) or hairy cell leukemia (n = 71). By combing morphologic features and phenotype, 54 specimens were considered positive, 62 negative, and 8 inconclusive. PCR analysis showed clonal IgH rearrangements in 46 positive and 6 inconclusive specimens. No clonal IgH rearrangements were present in 61 negative specimens. The 1 false-positive and most false-negative PCR results were likely due to sampling error or DNA degradation of the fixed tissues. In most cases, bone marrow involvement by NHL can be identified by histologic and immunohistochemical examination. Furthermore, clonality of the B-cell population can be detected by amplification of the IgH CDR3 on DNA extracted from bone marrow trephine biopsy sections, which can be helpful in cases diagnosed as inconclusive.     

Toward a final design for the Birmingham boron neutron capture therapy neutron beam

CD10 (CALLA) antigen is expressed in a wide variety of epithelial and nonepithelial tissues, but its most significant application is in the diagnosis and classification of certain types of malignant lymphoma and leukemia. CD10 is expressed in a high percentage of cases of acute lymphoblastic leukemia (ALL), follicular lymphoma, Burkitt's lymphoma, and some hematopoietic tumors. Although the antigen is not lineage specific, CD10 expression is widely used to define subgroups within B-ALL and is a useful tool for detecting the presence of leukemic blasts in the bloodstream. Currently available monoclonal antibodies to CD10 have been found to be effective only in fresh-frozen tissue and for techniques such as flow cytometry. We have used a recombinant protein corresponding to the whole of CD10 to generate a monoclonal antibody that is effective in paraffin-embedded tissue sections. We have used this antibody to assay for the presence of CD10 on a range of normal and pathological tissues. Strong staining was seen in lymphoid germinal centers, renal tubules, glomeruli, syncytiotrophoblast, hepatic parenchymal canaliculi, B-lineage ALL, follicle center cell lymphoma, and a proportion of cases of large-B-cell lymphoma. We believe that this antibody will be of value in the characterization of malignant lymphoma, in particular the differential diagnosis of small-B-cell lymphoma and subtyping of lymphoblastic leukemia, as well as the investigation of the significance of expression of CD10 in other normal and pathological tissues.     

Analysis of carbohydrate structures in basal laminar deposit in aging human maculae

PURPOSE: To analyze carbohydrate structures in basal laminar deposit (BLD), an extracellular material that accumulates between the retinal pigment epithelium (RPE) and Bruch's membrane. BLD has been shown to correlate positively with visual loss in age-related macular degeneration. METHODS: Thirteen postmortem human maculae with BLD were histochemically examined by light microscopy using the monoclonal antibody HNK-1 and seven lectins; canavalia ensiformis (ConA), soybean agglutinin (SBA), wheat germ agglutinin (WGA), dolichos bifloris (DBA), ulex europaeus (UEA-I), ricinius communis agglutinin I (RCA-I), and peanut agglutinin (PNA). Three maculae were stained with polyclonal antibodies against laminin and collagen type IV. RESULTS: BLD was exclusively stained by DBA and SBA, whereas Con A, WGA, UEA-I, RCA-I, and HNK-1 stained various other structures in the human macula as well. The main part of the BLD adjacent to Bruch's membrane stained with these lectins and the monoclonal antibody HNK-1, whereas only a small part of the BLD adjoining the RPE stained with antibodies against laminin and collagen type IV. Drusen stained neither with any lectin nor with any antibody. CONCLUSIONS: DBA and SBA, which bind specifically to an alpha-D-GalNAc moiety, are specific markers for the light-microscopic detection of BLD in human macular tissue. Furthermore, the authors conclude that BLD contains several carbohydrate structures other than the carbohydrate moieties on laminin and collagen type IV. If drusen contain carbohydrate structures, these must be different from those in BLD.     

Expression of CD44 standard and CD44 variant 6 in human lung cancer

We immunohistochemically examined the expression of CD44 standard (CD44 st) and CD44 variant 6 (CD44 v6) in 112 cases of primary lung cancer, and their relationship to the clinical milieu, including the clinical stage. In 46 cases of squamous cell carcinoma, expression of CD44 st was observed in 45.7% of the cases, and expression of CD44 v6 was observed in 60.9%. In 43 cases of adenocarcinoma, positive staining of CD44 st and CD44 v6 was seen in 2.3% and 4.7% of the cases, respectively. None of 21 small cell carcinomas was positive for CD44 st or CD44 v6. In squamous cell carcinomas, the expression of CD44 st and CD44 v6 was observed at a rate significantly higher than in other histologic type. Most specimens positive for CD44 st stained positively for CD44 v6. Therefore, it seems likely that the CD44 expression observed in squamous cell carcinoma of the lung was a variant CD44 containing the domain encoded by variant exon 6. The expression of CD44 v6 was not related to the clinical stage. Significant association between CD44 v6 and differentiation of squamous cell carcinoma was seen; 2/7 (28.6%) for poorly differentiated, 19/31 (61.3%) for moderately differentiated, and 7/8 (87.5%) for well differentiated squamous cell carcinomas (p = 0.02 by trend test). It was previously reported that CD44 st and CD44 v6 were expressed in both normal bronchial epithelium and squamous cell metaplasia. These results suggest that the expression of CD44 v6 in squamous cell carcinoma of the lung may reflect the immunohistochemical characteristics of the tissue from which such carcinoma emerge.