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PubMed1988

Characterization of basophil-like cells derived from nonhuman primate bone marrow.

In order to determine whether mast cells or basophils could be derived from nonhuman primate bone marrow, cells from bone marrow aspirates were cultured in the presence of concanavalin A-stimulated nonhuman primate spleen cell supernatants (CAS). Culture conditions were identical to those used for culturing mucosal-like mast cells from mouse bone marrow. In this situation, basophil-like cells (BLC) could be identified in liquid cultures and averaged 14-19 microM in size, were round or oval in appearance, had lobulated nuclei, and contained less than 100 metachromatically staining granules per cell. By electron microscopy, granules had dense oval or semilunar cores with surrounding fibrous whorls. BLC were peroxidase positive, chloroacetate esterase negative, stained positively with acid toluidine blue, and contained 0.1-0.3 pg histamine per cell. BLC expressed IgE receptors and were Leu 5b and Leu 16 negative. IgE-sensitized BLC released histamine after stimulation with antihuman IgE or the calcium ionophore A23187. [35S]-labeled proteoglycans were degraded with chondroitinase ABC but not with heparinase, indicating the absence of heparin in BLC. Thus, culture conditions that include the use of CAS and lead to the growth of mast cells from rodent bone marrow result in the growth of BLC from nonhuman primate bone marrow. These observations suggest that fundamental differences exist in the type of histamine containing cells that arise from rodent and primate bone marrow when such bone marrow cells are cultured under identical conditions.

Animals↗
PubMed2005

BAFF-R, the major B cell-activating factor receptor, is expressed on most mature B cells and B-cell lymphoproliferative disorders.

B cell-activating factor receptor (BAFF-R) is one of three known receptors for BAFF, a critical regulator of B- and T-cell function. In mice, BAFF-R is required for B-cell maturation and survival, and in mice and humans, the overproduction of BAFF is associated with autoimmune disease. We sought to determine the normal pattern of BAFF-R expression at specific stages of B- and T-cell development and whether this pattern of expression corresponds with related B- and T-cell neoplasms. Most circulating human B cells and a small subset of T cells are BAFF-R-positive. In reactive lymphoid tissues, BAFF-R is expressed by B cells colonizing the mantle zones, by a subset of cells within germinal centers, and rare cells in the interfollicular T-cell zone. BAFF-R is also expressed by B cells colonizing the splenic marginal zone. Seventy-seven (78%) of 116 cases of B-cell lymphoproliferative disorders were BAFF-R-positive by immunohistochemical and/or flow cytometric immunophenotypic analysis, including most cases of mantle cell lymphoma, follicular lymphoma, marginal zone lymphoma, chronic lymphocytic leukemia, hairy cell leukemia, and diffuse large B-cell lymphoma. In contrast, cases of precursor B lymphoblastic lymphoma, Burkitt lymphoma, and nodular lymphocyte-predominant Hodgkin lymphoma exhibit weak to negative staining for BAFF-R. All cases of classical Hodgkin lymphoma and T-cell lymphomas were BAFF-R-negative, including all cases of anaplastic large cell lymphoma, adult T-cell leukemia/lymphoma, angioimmunoblastic T-cell lymphoma, and peripheral T-cell lymphoma, unspecified. These findings highlight BAFF-R as a marker of both normal and neoplastic B cells and raise the possibility that BAFF-R expression is necessary for the survival of a subset of neoplastic B lymphocytes analogous to its known role in promoting normal B-cell maturation and survival.

B-Lymphocytes↗
PubMed1984

Ultrastructure of Klebsiella O3 lipopolysaccharide isolated from culture supernatant: structure of various uniform salt forms.

Various uniform salt forms of Klebsiella O3 lipopolysaccharide (KO3 LPS) isolated from culture supernatant were prepared as follows. Basic materials present in KO3 LPS were rigorously removed by electrodialysis and the electrodialyzed KO3 LPS was neutralized with NaOH, KOH, NH4OH, Ca(OH)2, tris(hydroxymethyl)aminomethane, or triethylamine. The ultrastructure of the uniform salt forms of KO3 LPS was examined using preparations stained with uranyl acetate. The sodium, potassium, ammonium, and trisaminomethane salt forms were structurally very similar to the natural form of KO3 LPS which consisted of a mixture of flat ribbon-like structures (average width of 16 nm and average thickness of 7 nm) and spheres with various diameters, both covered with fine hairy structures. When KO3 LPS was converted to the triethylamine salt form, the ribbon-like structures were disrupted into very small granules (7-9 nm X 9-15 nm). The calcium salt form consisted of particles and rods of various sizes and ribbon-like structures which were markedly extended (maximum width of 50 nm) and presented irregular shapes. When converted to the calcium salt form, the ribbon-like structures were extended and eventually divided into particles and rods. For reasons still unknown, the sodium salt of KO3 LPS was mostly stained positively with uranyl acetate in contrast to the natural form and the other uniform salt forms which were always negatively stained. In the positively stained preparation of the sodium salt form, it was clearly shown that the ribbon-like structures consisted of a bilayer.

Klebsiella↗
PubMed1993

Epstein-Barr virus in lingual epithelium of liver transplant patients.

Thirty-three liver transplant patients and 20 controls were examined for the presence of EBV in epithelium of the lateral border of the tongue by negative staining electron microscopy. Five of the specimens (15%) showed particles typical of the herpes virus family, while all controls were negative for EBV. In 3 of the 5 patients moderate oral hairy leukoplakia was observed clinically. Our results indicate that EBV may be expressed at the lateral border of the tongue of liver transplant patients, who in some cases show oral hairy leukoplakia clinically.

Adult↗
PubMed1983

Coaggregation of human oral Cytophaga species and Actinomyces israelii.

A total of 19 strains of oral Cytophaga sp. obtained from subgingival plaque deposits were tested for their ability to coaggregate with strains of Actinomyces israelii, A. viscosus, A. naeslundii, Streptococcus sanguis, S. mutans, S. salivarius, and S. mitis. Coaggregation was observed only with A. israelii. Based on their coaggregation patterns with eight A. israelii strains, the Cytophaga strains were distributed among three distinct groups: those that coaggregated with A. israelii PK16 but not with A. israelii W1011 (ATCC 29322), those that coaggregated with A. israelii ATCC 29322 but not with A. israelii PK16, and those that coaggregated with none of the eight A. israelii strains. In each of the coaggregations, prior heat treatment (85 degrees C, 30 min) of the Cytophaga cells prevented coaggregation, whereas identical treatment of the A. israelii cells had no effect. The ability of A. israelii PK16 to form adherent plaque on a tooth surface previously coated with Cytophaga plaque was tested with one of the coaggregating Cytophaga strains. White patches of A. israelii plaque were found covering both the amber-colored Cytophaga plaque on the cementum surface as well as the enamel surface to which Cytophaga strains do not adhere. Electron micrographs of thin-sectioned mixed-plaque material revealed both cell types in close proximity. In addition, electron micrographs of negatively stained coaggregated cells showed interbacterial adherence between surface fimbrae on A. israelii and outer membrane blebs on the gram-negative Cytophaga sp. The kinetics of binding of A. israelii to spheroidal hydroxyapatite and to root powder were indicative of a high-affinity binding system with comparatively large numbers of available binding sites on both substrata. These results indicate the highly specific nature of Cytophaga sp.--A. israelii recognition. The contribution of such recognition toward the mechanisms that are responsible for the indigenous nature of these oral bacteria is discussed.

Actinomyces↗
PubMed1996

Regulation of HIV-1 infection in astrocytes: expression of Nef, TNF-alpha and IL-6 is enhanced in coculture of astrocytes with macrophages.

'Restricted' human immunodeficiency virus type (HIV-1) infection of astrocytes is recognized in vivo in some pediatric and adult AIDS brains and in vitro in a small proportion of transfected primary fetal astrocytes. We investigated the extent of HIV-1JR-FL expression in fetal astrocytes and macrophages cultivated alone or together. Peak HIV-1 p24 antigen titres in supernatant fluids of macrophage cultures were increased with monocyte/macrophages from certain donors and were higher when macrophages were cocultivated with astrocytes. Structural HIV-1 gene (gp 41 and pol) products (protein and mRNA) were observed only in macrophages. Ten days after HIV-1JR-FL infection, astrocytes in a monoculture were stained negative or only weakly positive (1-2+) for Nef, whereas in a coculture up to 100% of astrocytes displayed Nef staining (up to 4+) in the cytoplasm. The streptavidine-biotine-peroxidase technique with certain monoclonal antibodies to Nef (Ovod et al, 1992) was specific for infected astrocytes. The intensity of Nef staining was higher in astrocytes cultivated with monocyte/macrophages from certain donors. In the coculture, tumor necrosis factor-alpha (TNF-alpha) was expressed in the astrocyte cytoplasm earlier after coinfection with HIV-1 and cytomegalovirus (CMV) compared to infection with HIV-1 alone. Interleukin-6 (IL-6) was secreted spontaneously and transiently in uninfected cocultures, but in a prolonged fashion following HIV-1 and HIV-1/CMV infections. The interactions between HIV-1- and CMV-infected macrophages and astrocytes lead to upregulation of TNF-alpha and IL-6 and enhancement of productive HIV-1 infection of macrophages and of 'restricted' HIV-1 infection of astrocytes with implications for the pathogenesis of AIDS dementia.

Astrocytes↗
PubMed2005

[Acute lymphoblastic leukemia with t(4;11)(q21;q23) after iodine-131 treatment for thyroid cancer].

A 49-year-old Japanese woman was diagnosed on March 1996 as having thyroid cancer with lung metastasis. Following a total thyroidectomy, she was treated with a total dose of 350 mCi iodine-131 (131I) for metastatic thyroid cancer. Four years later she returned to our hospital under the chief complaint of subcutaneous bleeding. Hematological examinations revealed marked leukocytosis associated with anemia and thrombocytopenia. A bone marrow aspiration showed a hypercellular marrow consisting of 90% blasts negatively stained by myeloperoxidase. Immunophenotyping of the blasts indicated they were CD19, 34, HLA-DR positive but CD3, 10, 13 negative. She was given the diagnosis of pro-B acute lymphoblastic leukemia (pro-B ALL). Cytogenetic analysis showed a chromosomal aberration t(4; 11)(q21; q23) and MLL-AF4 chimeric gene mRNA was detected by RT-PCR analysis. She had never been exposed to any kind of chemoradiotherapy other than 131I therapy and her leukemia showed a t(4; 11) chromosomal aberration and no expression of CD10 on the blasts, which are the characteristics frequently found in therapy-related pro-B ALL patients, suggesting a relationship between the development of pro-B ALL with t(4; 11) and 131I therapy. Although leukemia has been recognized as a late uncommon complication after 131I therapy for thyroid cancer, to the best of our knowledge this is the first patient who developed ALL with t(4 ;11) after 131I therapy among patients with thyroid cancer.

Brachytherapy↗
PubMed1986

Immunohistochemical localization of S100 protein in skin tumors.

We applied a peroxidase-antiperoxidase technique for S100 protein to 73 tumors of skin and skin adnexa. These included 15 eccrine tumors, 11 apocrine tumors, 18 tumors with differentiation toward hair, two sebaceous adenomas, one mixed tumor of the scalp, ten dermatofibromas, ten basal cell carcinomas, five squamous cell carcinomas, and one clear cell acanthoma. Consistent results were obtained. Occasional cells in eccrine tumors showed strong positive staining, as did the Langerhans' cells in the squamous cell carcinomas and the clear cell acanthoma. The cells of the apocrine tumors showed moderate to weak staining, and the tumors with differentiation toward hair, the sebaceous adenomas, and the mixed tumor of the scalp showed uniform negative staining, as did basal cell carcinomas and dermatofibromas.

Humans↗
PubMed1984

Extramammary Paget's disease. Arising in knee region in association with sweat gland carcinoma.

We report a case of extramammary Paget's disease (EMPD) arising in the knee region in association with an underlying sweat gland carcinoma. Inguinal lymph node metastases were present initially. Paget's cells, intradermal tumor cells, and metastatic tumor cells showed similar reactions to a variety of histochemical stains and positive results with immunohistochemical staining using carcinoembryonic antigen (CEA). Control sections in cases of Bowen's disease and superficial, spreading malignant melanoma showed a negative staining reaction with CEA, providing further evidence that this technique is useful in distinguishing Paget's disease (PD) from histologically similar conditions. We provide a summary of previous cases of EMPD arising in unusual locations and a brief consideration of possible mechanisms of the origin of PD.

Adenocarcinoma↗
PubMed1997

Indirect immunoperoxidase staining of Crithidia luciliae for detecting anti-dsDNA: comparison with other serodiagnostic tests.

The indirect immunoperoxidase (IIP) method was modified and improved for detecting anti-dsDNA. Using fetal calf serum to block the non-specific antibodies and staining with chromatic substrate solution at pH 6.2, the performance time is substantially decreased and the patterns of positive and negative staining are easily distinguished. IIP was compared with indirect hemagglutination (IHA), latex agglutination (LA) and the standard method indirect immunofluorescent technique (IFT). The sensitivities and specificities of the three methods were studied in 507 sera from various sources. Using IFT as the gold standard, sensitivities of IIP, IHA, LA were 98.18%, 88.18% and 50.91% respectively, and the corresponding specificities were 99.5%, 98.24% and 100%. There was a good correlation between titers of IFT and IIP (Spearman correlation coefficient = 0.77, p < 0.001) with no significant difference between the titer of both tests (Wilcoxon Matched-Pairs Signed-Rank test, p = 0.143). These results indicate that the modified IIP method is both highly sensitive and specific and only needs a light microscope to perform it.

Animals↗
PubMed1998

Perineurioma with ossification: a case report with immunohistochemical and ultrastructural studies.

We present the case of a peripheral nerve sheath tumor arising from the sciatic nerve in the thigh of a 42-year-old woman. Histologically, the tumor was composed of fascicles of spindle cells with extremely attenuated cytoplasmic processes. Regions of the tumor were heavily mineralized and fibrotic. The tumor was epithelial membrane antigen-positive and S100-negative. Staining for Leu-7 was positive in a patchy distribution. Type IV collagen was present between cells, and CD34 was negative in the tumor cells. Ultrastructural features included elongate cellular processes surrounded by discontinuous basal lamina and collagen. The features of the tumor therefore meet criteria for perineurioma. This rare tumor is found most often in the extremities in middle-aged woman. To our knowledge, the presence of bone formation in a perineurioma has not been described previously. The differential diagnosis includes other peripheral nerve sheath tumors, low-grade fibrous tumors, and synovial (monophasic) tumors. Evidence provided by electron microscopy and immunohistochemistry supports the diagnosis and classification of this unusual nerve sheath tumor as perineurioma with ossification. These findings expand our knowledge and criteria for classifying peripheral nerve sheath tumors.

Adult↗
PubMed1990

Prognostic correlation of HLA-DR expression in large cell lymphoma as determined by LN3 antibody staining. An Eastern Cooperative Oncology Group (ECOG) study.

Several previous studies employing surface-marker techniques suggest that HLA-DR antigen expression may correlate with prognosis in diffuse large cell lymphoma. Control studies in the authors' laboratory indicated that LN3 positivity in paraffin-embedded tissue correlates well with HLA-DR antigen expression. Accordingly they examined 212 cases of diffuse large cell lymphoma from one of Eastern Cooperative Oncology Group's (ECOG) high-grade malignant lymphoma treatment protocols. All patients studied had careful clinical follow-up of between 5 and 11 1/2 years from diagnosis and initiation of therapy. There was no correlation of strongly positive, positive, weakly positive, equivocal, or negative staining with survival. Cases that were LN3 negative had a median survival of 18.8 months versus a median survival of 39.4 months for all LN3-positive cases. However this difference was not statistically significant when using a log-rank test. The authors were unable to confirm that HLA-DR antigen expression, as defined by LN3, is prognostically valuable in diffuse large cell lymphoma in a multi-institutional study.

Antibodies, Monoclonal↗
PubMed1984

Differences in the morphology of isometric particles of some plant viruses stained with uranyl acetate as an aid to their identification.

Purified preparations of viruses with small polyhedral particles representing ten distinct taxonomic groups were examined by electron microscopy after negative staining with uranyl acetate. Comparisons of the relative size, shape and surface appearance of the particles established that some of them could be distinguished at the group level. However, the particles of viruses belonging to the bromovirus group could not be distinguished from those of the cucumovirus group, the nepovirus group from those of the comovirus group, and the tombusvirus group from those of the dianthovirus group. Furthermore, the particles of viruses of the sobemovirus, lutoevirus and tobacco necrosis virus groups were indistinguishable. The usefulness of the observed differences in the particle morphologies to virus identification is discussed.

Microscopy, Electron↗
PubMed2005

Immunohistochemistry in diagnostic surgical pathology of the prostate.

Immunohistochemistry (IHC) can play an important role in diagnostic surgical pathology of the prostate. Basal cell markers, such as the 34betaE12 antibody and antibodies directed against cytokeratin 5 and 6 or p63, are very useful for demonstration of basal cells as their presence argues against a diagnosis of invasive prostatic carcinoma (PC). However, several benign mimickers of PC, including atrophy, atypical adenomatous hyperplasia (AAH), nephrogenic adenoma, and mesonephric hyperplasia, can stain negatively with these markers, and thus, a negative basal cell marker immunostain alone does not exclude a diagnosis of benignancy. Although there are examples in the literature of high grade PC that stain focally with some of the basal cell markers, these cases are usually readily diagnosed based on H&E appearances and are unlikely to be confused with these benign mimickers. Alpha-methylacyl-coenzyme-A racemase (AMACR) is a sensitive marker of PC (except for a few uncommon variants: atrophic, foamy gland, and pseudohyperplastic variants), and its detection by immunohistochemical staining in atypical prostatic lesions can be very useful in confirming an impression of adenocarcinoma. AMACR expression can also be identified in high grade prostatic intraepithelial neoplasia (PIN), prostatic atrophy, AAH, and benign prostatic glands, and accordingly, a diagnosis of PC should not be based solely on a positive AMACR immunostain, especially when the luminal staining is weak and/or noncircumferential. The use of AMACR/basal cell antibody cocktails has been found to greatly facilitate the distinction between PC and its benign mimickers, especially when only limited tissue is available for staining. Prostate specific antigen (PSA) and prostate specific acid phosphatase (PSAP) are both quite sensitive and fairly specific markers of PC (there are a few nonprostatic tumors that can express one or both), and are both very helpful in establishing or confirming the diagnosis of PC when the differential diagnosis includes other tumors that can involve the prostate such as urinary bladder urothelial carcinoma. 34betaE12, p63, thrombomodulin, and uroplakin III are additional urothelial associated markers useful in this differential diagnosis. CDX2 and villin are useful markers to diagnostically separate colonic adenocarcinoma from PC. AMACR positivity and negative basal cell marker reactions are useful to confirm the presence of residual PC after hormonal or radiation therapy. Pan-cytokeratin, PSA, and PSAP can also highlight subtle infiltrates of PC with hormonal or radiation therapy effect. PSA and PSAP immunohistochemical stains are valuable in confirming metastatic carcinoma as being of prostatic origin and should always be utilized in the diagnostic evaluation of metastatic adenocarcinoma of unknown primary origin in males.

Biomarkers, Tumor↗
PubMed1992

Clinical evaluation of radioimmunoimaging with 131I-C0C183B2 monoclonal antibody against ovarian carcinoma by intraperitoneal injection.

Forty-eight cases subjected to radioimmunoimaging (RII) by intraperitoneal injection with 131I-C0C183B2 monoclonal antibody (MAb) prepared in our laboratory were studied. Thirteen of 14 cases of proved primary ovarian carcinoma were positive. In 11 follow-up cases of ovarian carcinoma after initial surgery and chemotherapy, 5 recurrences were positive and 6 cases without recurrence were negative; all were confirmed histopathologically after a second operation. One false negative was ovarian mucinous adenocarcinoma, which also negatively stained with C0C183B2 by the peroxidase anti-peroxidase method. Twenty of 23 cases of nonepithelial or metastatic carcinoma of the ovary, benign tumors, and benign diseases were negative. The sensitivity and specificity were 94.7 and 89.7%, respectively. If patients had complications with ascites, the MAb which positively stained with the cancer cells in the ascites was chosen for RII. For follow-up cases PAP staining with the tumor tissue from the initial surgery and the MAb should be done before RII. These are the principal factors that increase the positive rate and accuracy of RII. The intraperitoneal route seems to be a valuable method for clinical staging and tumor localization as well as for follow-up use.

Adult↗
PubMed2004

Correlation between responsiveness of neoadjuvant chemotherapy and apoptosis-associated proteins for cervical adenocarcinoma.

OBJECTIVE: Adenocarcinoma of the uterine cervix appears to be increasing in prevalence and it has been suggested that these tumors tend to be less sensitive to radiation therapy and to chemotherapy than squamous carcinomas. In the present study, 29 patients with locally advanced cervical adenocarcinoma (bulky IB-IVB) were treated with neoadjuvant chemotherapy (NAC) using cisplatin, aclacinomycin-A and mitomycin-C, followed by radical surgery or irradiation. METHODS: To predict the prognosis and response to the chemotherapy, the expression of apoptosis associated-proteins, p53, p21WAF1/CIP1, Bcl-2 and activated caspase-3 was evaluated for tumor samples by immunohistochemistry. RESULTS: Of the analyzed clinicopathological factors, the overexpression of p53 was frequently observed in endocervical-type adenocarcinoma, nonresponders to chemotherapy and the grade 0 histologic effect of the chemotherapy. Positive staining of Bcl-2 was frequently observed in the early stage and had a better prognosis than for patients with the negative staining; however, there was no correlation between responders and nonresponders to chemotherapy. The expression of p21WAF1/CIP1 and caspase-3 was not correlated to the clinicopathological factors. CONCLUSION: In this study, the overexpression of p53 was found to be a factor to predict the chemoresistance and positive expression of Bcl-2 indicated as a better prognostic value. For p21WAF1/CIP1 and caspase-3, further analysis is necessary.

Aclarubicin↗
PubMedDate not supplied

Enzymatic modification of self-assembled peptide structures with tissue transglutaminase.

A de novo peptide that self-assembles into fibrillar structures and serves as a substrate for the cross-linking enzyme tissue transglutaminase was developed (Ac-QQKFQFQFEQQ-Am). Congo red staining, circular dichroism, and FTIR spectroscopy showed that this 11-amino acid peptide produced predominantly beta-sheet structures. TEM with negative staining and quick-freeze deep etch (QFDE) TEM showed that the peptide structures were composed of a highly entangled fibrillar network. These beta-sheet fibrillar nanostructures were then covalently coupled to pendant amine-containing biomolecules via tissue transglutaminase. MALDI-TOF mass spectrometry and HPLC were utilized to monitor the extent of the transglutaminase modification of the peptide, showing that as many as five glutamines in the peptide were reactive via transglutaminase for covalent conjugation. This strategy, based on the post-assembly modification of a self-assembling peptide, has potential applications for tailoring supramolecular structures for drug delivery, tissue engineering, or other biomedical applications.

Amino Acid Sequence↗
PubMed2002

Exaggerated signet-ring cell change in stromal nodule of prostate: a pseudoneoplastic proliferation.

A stromal nodule of the prostate was incidentally identified in a simple prostatectomy specimen from a 66-year-old man with benign prostatic hyperplasia. Microscopically, the nodule consisted of short spindly cells with bland nuclear features. Many of the cells in the nodule, however, contained a large, clear cytoplasmic vacuole that displaced and indented the nucleus, generating signet-ring cell morphology. Immunohistochemically, these cells were strongly positive for vimentin and weakly positive for desmin, suggesting a myofibroblastic nature. Further immunostains demonstrated the cells to be negative for cytokeratins and prostate-specific antigen, excluding the possibility of signet-ring cell carcinoma. The cytoplasmic vacuoles also stained negative for mucin production. Electron microscopy revealed no intracytoplasmic lumina. Notably, thermal effect or other signs of cellular injury, frequently associated with signet-ring cell change seen in prostate specimens obtained by transurethral resection and needle biopsy, were not appreciated in this stromal nodule. This case demonstrates that signet-ring cell change may occur in benign, hyperplastic, prostatic stromal cells in the absence of cellular damage.

Aged↗