Strong Cytoplasmic Reactivity Research Articles

Pneumoperitoneum Modifies Serum and Tissue CCL2-CCL5 Expression in Mice.

Background and Objectives:Laparoscopy is the preferred method when operating in the abdomen. In this study, we evaluated systemic and morphological peritoneal cytokine modifications (RANTES/CCL5 and MCP-1/CCL2) due to CO2 pneumoperitoneum in rats.Methods:Twenty-five prepubertal Sprague-Dawley rats were randomized into three groups. Pneumoperitoneum lasting 30 minutes, was induced with a flow of 0.5 L/min, in two groups (S1 and S2, n = 20), at a P/CO2 of 6 and 10 mm Hg, respectively. In the control group (C, n = 5), only anesthesia was carried out. All animals were sacrificed after 24 hours. The serum of the rats was collected for ELISA, and the levels of the cytokines RANTES and MCP-1 were investigated. An immunohistochemical analysis of RANTES and MCP-1 was performed on samples of the peritoneum, and the morphological evaluation was conducted with a blinded evaluation by two independent, experienced pathologists by using a grading system (0, 1+, 2+, 3+: no, faint, moderate, and strong reactivity, respectively).Results:RANTES mean levels were significantly different in the S1, S2, and C groups (70.3 ± 2.26, 58.23 ± 4.32, 29.66 ± 4.03, respectively, P = .0001). The levels of MCP-1 were 32.1 ± 1.63 in the S1 group, 27.0 ± 9.26 in the S2 group, and 16.4 ± 9.55 in the C group (P = .159). Normal control peritoneum showed little reactivity, whereas a moderate to strong cytoplasmic reaction to anti-CCL5/CCL2 antibodies was observed in mesothelial and inflammatory cells in the S1 and S2 groups.Conclusion:CO2 pneumoperitoneum evokes an inflammatory response by modifying plasma RANTES levels and peritoneal CCL5/CCL2 expression.

Histopathological and immunohistochemical study of extra skeletal chondrosarcoma in lion (Panthera leo)

A hard greyish white coloured growth was detected in the lower region of the abdomen near the sternum in a 23-year-old male lion (Panthera leo) and was examined histopathologically and immunohistochemically. After routine processing, tissues were subjected to hematoxylin and eosin stain and to the marker, VEGF. The mass was composed of numerous pleomorphic chondrocytes within the basophilic matrix. The mean AgNOR value obtained was 4.49. The expression of VEGF in the cytoplasm of the neoplastic cells was noticed. Based on the histopathological features and the strong cytoplasmic reactivity of VEGF, the present case was diagnosed as extra skeletal chondrosarcoma.

Increased Tumorigenesis In Ribosomal Proteins L5 and S24 Heterozygous Mice

Diamond-Blackfan anemia (DBA) is a congenital red blood cell aplasia inherited in an autosomal dominant pattern caused by mutations in ribosomal protein (RP) genes and in an X-linked recessive pattern by GATA1 mutations. Heterozygous mutations and large deletions in 11 RP genes, RPS19, RPS24, RPS17, RPL5, RPL11, RPL35A, RPS7, RPS10, RPS26, RPL26, and RPL15, are present in ∼65% of DBA patients. DBA is associated with congenital abnormalities in ∼50% of patients and with increased risk of malignancy. To investigate the molecular pathogenesis of RPL5 and RPS24 gene mutations, we generated two murine lines of heterozygous mice, Rpl5 and Rps24, by knocking-out exons 1-8 in the Rpl5 gene and exons 2-3 in the Rps24 gene in C57BL/6 mice. Knock-out of both alleles of Rpl5 and Rps24 genes are embryonic lethal. In contrast, heterozygous mice exhibited normal hematological phenotype, as well as normal Rpl5 and Rps24 RNA and protein levels in their tissues, suggesting that the presence of one allele was sufficient to support the normal function of ribosomal proteins L5 and S24 in mice. To evaluate the risk of cancer development in Rpl5 +/- and Rps24 +/- mice, we monitored these mice and wild type mice until late age. Out of 21 Rpl5 +/- mice (between the ages of 14 and 26 months), two mice developed tumors at 22 months of age and two mice were euthanized due to severe dermatitis at the same age. Similarly, we have been monitoring 23 Rps24 +/- mice between 15 and 26 months of age. One of these mice developed a tumor at 17 months of age, five mice were euthanized due to severe dermatitis between the ages of 17 and 19 months, and two mice were euthanized due to injuries at ages 15 and 29 months. We also monitored 20 control wild-type mice ranging from 13 to 26 months of age. To this date, no tumors have been detected in wild-type mice, although nine of these mice developed severe dermatitis and were euthanized. Histological and immunohistochemical studies were performed to determine the nature of tumors in Rpl5 +/- and Rps24 +/- mice. Comparison of tumor tissues with normal skin from wild-type or Rpl5 +/- and Rps24 +/- with no detected tumors showed that all tissues had normal epidermis and underlying dermis, but connective tissues from tumor sections consisted of a densely cellular neoplasms composed of predominantly atypical spindle shaped cells arranged in intersecting fascicles. The tumor cells had strong cytoplasmic reactivity for vimentin and negative staining for S100, CD45, and pan-keratin, consistent with a high-grade spindle cell sarcoma. Recent studies conducted by the DBA Registry of North America revealed that out of 608 DBA patients, 18 with median age of 41 years developed various types of cancer including sarcomas, colon cancer, and acute myeloid leukemia. The relative risk of cancer in DBA was increased 5.4 fold compared to general population (Vlachos, et al., 2012). Our studies also suggest the correlation between ribosomal protein gene mutations and cancer. However, further studies are required to better understand the underlying molecular mechanism. Disclosures:No relevant conflicts of interest to declare.

Diagnostic value of a novel fully automated immunochemistry assay for detection of ALK rearrangement in primary lung adenocarcinoma

BackgroundTo evaluate the diagnostic value of a novel fully automated immunohistochemistry (IHC) assay for detection of anaplastic lymphoma kinase (ALK) fusion in a large number of ALK-positive lung adenocarcinoma (ADC) patients. Patients and methodsWe tested 196 lung ADCs for ALK rearrangement by two IHC assays (Ventana pre-diluted ALK D5F3 antibody with the Optiview DAB IHC detection kit and Optiview Amplification kit, D5F3 by Cell Signaling Technology (CST) with Ultraview DAB detection kit by Ventana), fluorescence in situ hybridization (FISH) and real-time reverse transcription–PCR (RT–PCR). CST ALK IHC was scored using the scoring scheme of 0, no staining; 1+, faint; 2+, moderate; and 3+, strong cytoplasmic reactivity in ≥10% of tumor cells. As for Ventana IHC, a binary scoring system (positive or negative for ALK status) was adopted for evaluating the staining results. ResultsAmong 196 cases tested, 63 (32%), 65 (33%), 70 (36%), and 69 (35%) cases were ALK positive by FISH, Ventana IHC, CST IHC, and RT–PCR, respectively. The sensitivity and specificity of Ventana IHC were 100% and 98%, respectively. Two Ventana IHC-positive cases, which were also CST IHC score of 3+, showed FISH negative, but their ALK rearrangement was confirmed by RT–PCR and direct sequencing. The sensitivity and specificity of CST IHC with staining intensity score of 1+ or more were 100% and 95%, respectively. Five (25%, of 20) patients with CST IHC score of 1+ were both FISH and RT–PCR negative. The sensitivity and specificity of RT–PCR for detection of ALK fusion were 98% and 95%, respectively. The total accordance rate between ALK RT–PCR and Ventana IHC was 97%. ConclusionsThe novel fully automated IHC assay is a reliable screening tool in routine pathologic laboratories for identification of patients with ALK rearrangement for targeted therapy in lung ADC.

30 Year-Old Male with Headaches

30 Year-Old Male with Headaches

Ontogeny and disease responses of Langerhans-like cells in lymphoid tissues of salmonid fish

The ontogeny and disease responses of Langerhans-like cells within lymphoid tissues of Atlantic salmon, Salmo salar, and rainbow trout, Oncorhynchus mykiss, were investigated. These cells were studied in situ with the use of two markers: the ultrastructural presence of Birbeck-like granules and immunohistochemistry with an antibody against human langerin/CD207 that cross-reacts with salmonid tissues. The appearance of Birbeck-like granules was observed in rainbow trout at 2 weeks post-hatch (PH) in the thymus and anterior kidney prior to the development of the spleen. Spleen first appeared at 3 weeks PH in both Atlantic salmon and rainbow trout, and Birbeck-like granules were observed within cells of the newly developed spleens. The cross-reactivity of langerin as seen by immunohistochemistry was not clearly observed in kidney and spleen until 9 weeks PH, when a strong cytoplasmic reaction was observed. To study langerin-positive cells in spleen and kidney during disease, microsporidial gill disease (MGD) in rainbow trout was used as a known disease model inducing a strong cell-mediated adaptive immune response. Langerin-positive cells in healthy fish were seen predominantly in the spleen, and only low numbers were present in the anterior kidney. During MGD, langerin-positive cell numbers were elevated in the anterior kidney and were significantly higher during 5, 6, and 10 weeks post-exposure (PE) compared with healthy control tissue. During MGD, the distribution of langerin-positive cells in the spleen and anterior kidney shifted from having significantly higher numbers of cells in the spleen than in the kidney in controls and at 1 and 4 weeks PE to having a similar distribution of the cells in the two organs at 2, 3, 5, and 6 weeks PE. By 10 weeks PE, significantly higher numbers of langerin-positive cells occurred in the anterior kidney compared with the spleen.

Corneal invasion by hemangiosarcoma in a horse

A 15-year-old gray Arabian gelding presented for evaluation of a lateral limbal mass extending across approximately 30% of the cornea. Grossly, the raised mass appeared nonpigmented, smooth, and irregular in shape, with an area of central necrosis and serosanguinous discharge. The mass was removed via lamellar keratectomy and histopathologic evaluation revealed features characteristic of hemangiosarcoma (HSA), including irregular vascular channels lined by a plump spindle cell population. Immunohistochemistry results showed that the neoplastic cells lining the vascular channels present diffuse and strong cytoplasmic reaction with von Willebrand Factor and the perivascular spindle cells exhibit moderate cytoplasmic reaction for smooth muscle actin. A lack of cytokeratin staining definitively excluded a diagnosis of atypical squamous cell carcinoma. Smooth muscle actin staining of the perivascular cells adjacent to the neoplastic endothelial cells is not a feature commonly described in HSA and has not been reported in previous cases of equine HSA. The horse remained in good health 21 months postkeratectomy and has exceeded the survival time of previously documented equine ocular HSA cases where more extreme surgical excision was performed.

Diagnostic use of nuclear Β-catenin expression for the assessment of endometrial stromal tumors

Alterations in Β-catenin degradation cause it to accumulate to immunohistochemically detectable levels in the nuclei of tumor cells. Although it has been shown that nuclear Β-catenin immunostaining is useful for the diagnosis of some mesenchymal tumors, there is little known about Β-catenin expression in endometrial stromal tumors. In this study, nuclear Β-catenin immunoreactivity was evaluated in normal endometrium and endometrial mesenchymal tumors and then compared with that of CD10. The endometrial mesenchymal tumors evaluated included endometrial stromal nodules (n=2), low-grade endometrial stromal sarcomas (n=12), undifferentiated endometrial sarcomas (n=8) and uterine cellular leiomyomata (n=9). In addition, direct DNA sequencing of Β-catenin exon 3 was conducted in 15 endometrial stromal tumors. Normal endometrial stromal cells showed strong cytoplasmic reactivity for CD10 but no detectable reactivity for Β-catenin. Nuclear Β-catenin immunoreactivity was detected in 11 low-grade endometrial stromal sarcomas (92%) and 6 undifferentiated endometrial sarcomas (75%). Ten low-grade endometrial stromal sarcomas (83%) and six undifferentiated endometrial sarcomas (75%) were positive for CD10. Eight low-grade endometrial stromal sarcomas (67%) exhibited diffuse, strong nuclear immunoreactivity with Β-catenin, whereas only four cases (33%) expressed diffuse, strong immunoreactivity with CD10. All nine cases of uterine cellular leiomyomata were completely negative for both CD10 and Β-catenin. Β-catenin mutations were rare in endometrial stromal tumors. Taken together, these results indicate that nuclear Β-catenin immunostaining can serve as a sensitive immunohistochemical marker for the diagnosis of endometrial stromal tumors and is useful for differentiating low-grade endometrial stromal sarcomas from uterine cellular leiomyomata.

Subcutaneous Neoplasms of the Ventral Abdomen with Features of Adrenocortical Tumors in Two Ferrets

A ventral abdominal subcutaneous mass was removed from each of 2 young adult spayed female ferrets. In both cases, the neoplasms were composed of islands of polygonal cells separated by interlacing streams of spindloid cells reminiscent of ferret adrenocortical tumors with smooth muscle proliferation. Immunohistochemically, the polygonal cells demonstrated strong cytoplasmic reactivity for inhibin and weak cytoplasmic reactivity for pancytokeratin and S-100 protein. Spindloid cells demonstrated strong cytoplasmic reactivity for alpha smooth muscle actin, muscle-specific actin, desmin, and glial fibrillary acidic [corrected] protein. Ultrastructurally, the polygonal cells contained numerous intracytoplasmic clear vacuoles, mitochondria, scant rough endoplasmic reticulum, and few intermediate filaments. In one tumor, vesicular tubular mitochondria were found in polygonal cells. The spindloid cells contained numerous aggregates of parallel intermediate filaments. The histologic, immunohistochemical, and ultrastructural findings are suggestive of adrenocortical tumors with smooth muscle proliferation, but cannot be differentiated from an ovarian gonadal stromal tumor. Neither ferret had a clinically detected primary adrenal gland tumor or clinical signs of adrenal-associated endocrinopathy.

Antibodies targeting p63 react specifically in the cytoplasm of breast epithelial cells exhibiting secretory differentiation

The nuclear detection of p63 in myoepithelial cells of the breast has been useful in identifying possibly invasive carcinomas. While examining myoepithelial cells for p63 a very strong cytoplasmic reaction product was noted in secretory cells. The aim was to determine whether this reaction is specific for p63 and indicative of all breast secretory cells. Thirty breast specimens were tested immunohistochemically for p63 protein. These included seven with benign secretory changes, 10 secretory carcinomas (nine invasive), one microglandular adenosis, three lobular neoplasias, four invasive ductal carcinomas, three clear cell carcinomas, one squamous cell carcinoma and one mucinous carcinoma. Only cells exhibiting secretory changes or secretory carcinoma were cytoplasmically reactive for p63. The positive reaction was also present as an intraluminal secretory product. This reaction was not seen in cells undergoing apocrine differentiation or in other cells containing secretory vacuoles. Cells with secretory changes contain p63 protein or an antigenic equivalent. The detection of p63 protein continues to have considerable value for the identification of myoepithelial cells and thus the determination of invasion, but will also have value in the determination of secretory carcinomas of the breast and in understanding their development.

Hypoxia-inducible factor (HIF1A and HIF2A), angiogenesis, and chemoradiotherapy outcome of squamous cell head-and-neck cancer

Purpose : Hypoxia-inducible factors HIF1α and HIF2α (HIFαs) regulate the expression of a variety of genes encoding proteins related to angiogenesis and to anaerobic metabolism of cells exposed to hypoxic stress. Their putative role as markers of clinically relevant hypoxia and, therefore, as predictors of response to chemoradiotherapy is herein examined. Patients and Methods : Using immunohistochemistry, we assessed the expression of HIFαs in normal head-neck mucosa and in 75 cancer specimens from patients with locally advanced squamous cell head-and-neck cancer (SCHNC), treated with concurrent carboplatin chemoradiotherapy. Results : Head-and-neck mucosa from normal individuals did not show any HIF1α or HIF2α reactivity. SCHNC showed a varying expression of HIFαs ranging through negative reactivity, to weak or focally strong cytoplasmic reactivity, or to strong diffuse cytoplasmic/nuclear reactivity. Fifty-two percent and 33% of cancer samples showed the latter expression pattern for HIF1α and HIF2α, respectively, and were considered to bear “high” HIF reactivity. Bone/cartilage involvement was more frequent in tumors with high HIF1α expression ( p = 0.05). HIF1α and HIF2α overexpression were significantly associated with high microvessel density ( p = 0.002 and 0.02, respectively) and with VEGF expression ( p = 0.01 and 0.005, respectively). HIF1α was related to high thymidine phosphorylase expression ( p = 0.03), whereas VEGF/KDR-activated tumor vasculature was significantly more frequent in HIF2α-overexpressing tumors ( p = 0.02). High HIF1α and HIF2α were associated with incomplete response to chemoradiation ( p = 0.007 and p = 0.02, respectively). In univariate analysis, high HIF1α and HIF2α expression were significantly associated with poor local relapse-free survival ( p = 0.003 and 0.003, respectively) and with poor overall survival ( p = 0.05 and 0.001, respectively). In multivariate models, HIF2α expression was an independent prognostic factor. In biopsies performed after the delivery of 20 Gy of radiotherapy, upregulation of HIFαs was noted in some cases. Conclusions : It is concluded that the overexpression of HIFαs in SCHNC is related to locally aggressive behavior, to intensification of angiogenesis, and to an important resistance to carboplatin chemoradiotherapy.

Diagnostic use of muscle markers in the cytologic evaluation of serous fluids.

Differentiating reactive mesothelial cells from malignant mesotheliomas and from adenocarcinomas can be diagnostically challenging when based solely on the morphologic examination of serous fluids. The diagnosis even after the use of standard immunohistochemical stains may at times be inconclusive because of the variable reactivity of mesothelial cells for these markers. Pathologists and cytologists underutilize reactivity for desmin, a feature of mesothelial cells apparently not shared by adenocarcinomas. The purpose of this study was to evaluate the extent to which mesothelial cells express muscle differentiation and to assess the diagnostic utility of muscle markers in distinguishing reactive mesothelial cells from malignant mesotheliomas and adenocarcinomas. Archival paraffin-embedded cell blocks of serous fluids from 24 cases of reactive mesothelial cells, 14 cases of malignant mesothelioma, and 56 cases (14 cases from each) of metastatic adenocarcinoma from the lung, breast, ovary, and gastrointestinal tract were retrieved. Five cases of omentum with unremarkable mesothelial cells were also included in the study. All cases were stained for desmin, actin, myoglobin, and myogenin and evaluated independently by two observers. Strong cytoplasmic reactivity for desmin was noted in 22 of 24 cases (92%) of reactive mesothelial cells. The reactive mesothelial cells did not express actin, myoglobin, or myogenin. All cases of malignant mesothelioma and metastatic adenocarcinoma were negative for the four muscle markers. The mesothelial lining and scattered subserosal cells in the omental sections were positive for desmin. Because desmin was expressed only in benign mesothelial cells, it may serve as a reliable marker in distinguishing reactive mesothelial cells from mesothelioma or from adenocarcinoma. Awareness of this staining pattern is also important to avoid pitfalls when evaluating body fluid specimens from patients with a history of tumors expressing muscle differentiation.

Earthworm leukocytes react with different mammalian antigen-specific monoclonal antibodies

We identified conserved molecules (enzymes, peptides, cytokines) that might play a role in invertebrate innate immunity. We found these molecules by immunoserological and immunohistochemical methods in association with coelomocytes, leukocytes located in the coelomic cavity of the earthworm Eisenia foetida. We detected the enzyme Cu-Zn-superoxide-dismutase (SOD), cytokines (tumor necrosis factor-alpha, TNFalpha; transforming growth factor-alpha, TGFalpha; and alpha peptide hormone, thyreotrope stimulating hormone, TSH) in earthworm coelomocytes with monoclonal antibodies developed originally against human and/or mouse antigens. Three coelomocyte subpopulations were identified according to their form, size and granularity by microscopic and flow cytometric analysis. These cell populations showed different reactivity with antibodies against mammalian cell surface (CD) markers and different intracellular antigens. Two coelomocyte types showed cell surface positivity with anti-Thy-1 (CD90), CD24 and TNF-alpha antibodies. Strong cytoplasmic reaction was shown with anti-TNF-alpha and anti-SOD mAbs and a weaker but unambiguous reaction with thyroid stimulating hormone (TSH) in two cell populations. The third population was negative for all of the monoclonal antibodies. Our flow cytometric results were confirmed by confocal microscopy both on the cell surfaces and intracellularly.

Angiogenesis and apoptosis-related protein (p53, bcl-2, and bax) expression versus response of gastric adenocarcinomas to paclitaxel and carboplatin chemotherapy.

The role of angiogenesis and apoptosis-related proteins in defining response to chemotherapy is poorly understood. We examined the microvessel density (MVD) and the expression of p53, bcl-2, and bax proteins in a series of 28 locally advanced gastric adenocarcinomas, treated with paclitaxel and carboplatin. A strong cytoplasmic reactivity in more than 10% of cancer cells was recorded in 25% of cases for p53 protein, and in 14% and 64% of cases for bcl-2 and bax proteins, respectively. Microvessel density was assigned in three categories: low (<35), medium (35-60), and high (>60). Tumors of medium MVD showed a significantly higher response rate compared with those of high or low MVD (p = 0.01 and 0.001, respectively), and prognosis was significantly better in this group of patients with medium MVD tumors (p < 0.02). Loss of bax protein expression was somewhat more frequent in tumors resistant to chemotherapy, but this difference was not of statistical significance. Nuclear p53 reactivity was associated with higher MVD (p = 0.02). The expression of p53 and bcl-2 did not influence the outcome of treatment. The present study suggests that although apoptosis-related proteins may have a role in defining response to taxanes, parameters related to tumors' vasculature, such as drug availability or angiogenic tissue regeneration, may be equally important.

Expression of the intermediate filament peripherin in extraskeletal myxoid chondrosarcoma.

The embryologic histogenesis of cartilage is not well characterized. While cranial cartilage is believed to be derived from pluripotential precursor cells of the neural crest, chondrocytes found elsewhere in the body are thought to be derived from mesoderm. As such, soft tissue tumors with cartilaginous differentiation may be related to neural crest or mesoderm. Peripherin is an intermediate filament encoded on chromosome 12, involved in growth and development of the peripheral nervous system. Peripherin is apparently expressed exclusively in cells derived from the neural crest and neural tube. A group of six soft tissue tumor types was selected because they are either of controversial differentiation or cytogenetically related to chromosome 12. A total of 41 cases was evaluated with antibodies against the intermediate filament peripherin. A panel of neural and neuroendocrine differentiation markers was used in selected cases. Three of five extraskeletal myxoid chondrosarcomas showed strong cytoplasmic reactivity with anti-peripherin. No peripherin expression was noted in any of eleven epithelioid sarcomas, eight liposarcomas, seven conventional chondrosarcomas, four neurothekeomas, three alveolar soft part sarcomas, or three clear cell sarcomas. The finding of peripherin expression in some extraskeletal myxoid chondrosarcomas may suggest the ability of some tumors to demonstrate both neural and chondroid differentiation.

Isoforms of the human PDZ-73 protein exhibit differential tissue expression

Patients with renal and colon cancer frequently develop IgG autoantibodies toward the NY-CO-38/PDZ-73 antigen, a protein of 652 amino acids (73 kDa) which contains three copies of the PDZ protein–protein interaction domain. The gene encoding PDZ-73 mapped to chromosome 11p15.4–p15.1. Additional tissue-specific isoforms were identified: PDZ-45, which lacks the third PDZ domain and the putative PEST protein degradation motif, is expressed in kidney, colon, small intestine, brain and testis; PDZ-54 and PDZ-59, which also lack the third PDZ domains, have unique carboxyl terminal amino acids and are expressed in brain, kidney, bladder, colon cancer and renal cancer; and a putative PDZ-37 isoform, containing only the third PDZ domain, that is expressed in the central nervous system. Immunohistochemical staining with anti-PDZ 73 monoclonal antibodies showed strong cytoplasmic reactivity in epithelial cells of the small intestine, colon and kidney tubules, with a prominent apical staining pattern in cells of the small intestine. The reactivity pattern of the antibodies with various tissues correlated with the mRNA expression pattern of the PDZ-45 isoform. The existence of multiple PDZ-73 isoforms with variations in tissue distribution, PDZ domains, protein degradation sequences and carboxyl terminal structure indicate that these isoforms have distinct tissue-specific functions.

Immunohistochemical Expression of E-Cadherin in Salivary Glands and Their Tumors.

E-cadherin is a calcium dependent cell adhesion molecule, important in cell to cell interactions in epithelial tissues. The present study examined E-cadherin expression in normal salivary glands, pleomorphic adenoma, Warthin's tumor, mucoepidermoid carcinoma, acinic cell carcinoma, adenoid cystic carcinoma and adenocarcinoma of salivary glands in paraffin sections using a monoclonal antibody (5H9). This study is firstly reported E-cadherin expression in the salivary gland and tumors.In normal submandibular and parotid gland, E-cadherin staining was confined to the cell membrane of acinar and ductal cells. In excretory ducts, high columnar cells showed the strongest reaction at the basal aspect and ductal basal cells were weakly positive or negative, the basement membrane zone lacked staining. No E-cadherin reaction was observed in modified myoepithelial cells and plasmacytoid cells. In pleomorphic adenoma and mucoepidermoid carcinoma, E-cadherin was positive at the lateral cell membrane or whole cell membrane of duct-like structure and epidermoid cells. Acinic cell carcinoma was negative for E-cadherin. In adenoid cystic carcinoma, the expression was only found in cribriform areas. In adenocarcinoma, the staining was seen in the cell membrane of duct like structures and occasional cells showed a strong cytoplasmic reaction. Positive E-cadherin staining in salivary gland tumors was higher in benign tumors than in malignant tumors.

Diagnostic relevance of peripheral blood immunocytochemistry in hairy cell leukaemia.

AIMS--(1) To assess the diagnostic relevance of peripheral blood immunocytochemistry in hairy cell leukaemia (HCL); (2) to compare the immunostaining of bone marrow biopsy specimens with bone marrow and peripheral blood cytospins; (3) to evaluate the sensitivity of the different markers used; (4) to identify the ultrastructural localisation of DBA.44 in HCL variant. METHODS--Immunoenzymatic staining procedures, immunoperoxidase and immunoalkaline phosphatase, were used with a panel of monoclonal antibodies directed to HCL associated antigens. Ultrastructural immunostaining was performed using colloidal gold conjugated antibodies. RESULTS--HCL showed strong cytoplasmic reactivity for CD22, CD25, CD103, DBA.44, kappa, or lambda light chains. Peripheral blood diagnostic hairy cells were found in all the cases with absolute counts ranging from 0.11 x 10(9)/l up to 6.4 x 10(9)/l and values increasing with the size of the spleen. A median of 36.5% of leukaemic cells was found in bone marrow aspirates and 70% in bone marrow trephine specimens. The monoclonal antibodies CD22 and DBA.44 showed the highest and the lowest percentage of positive hairy cells, respectively; this difference was statistically significant (p = 0.0025). Ultrastructural immunolabelling with DBA.44 showed a cytoplasmic membrane localisation of the antigen in one case of HCL variant. CONCLUSIONS--(1) Immunocytochemistry is a useful technique which enhances the accuracy of diagnosis in HCL; (2) peripheral blood immunocytochemistry is recommended because it highlights hairy cells in all cases; (3) CD22 appears to be the most sensitive of the markers tested; (4) ultrastructural analysis is a useful tool in selected cases of HCL variant.

Immunocytochemical Demonstration of Proopiomelanocortin-derived Peptides in Pituitary Adenomas of the Pars Intermedia in Horses

Adenomas of the pars intermedia from 19 horses and normal pituitary glands from seven horses were evaluated histologically and immunocytochemically for adrenocorticotropic hormone (ACTH), alpha-melanocyte-stimulating hormone (alpha-MSH), beta-endorphin (beta-END), proopiomelanocortin (POMC), prolactin, neuron specific enolase, and glial fibrillary acidic protein (GFAP). The 26 horses ranged in age from 7 to 31 years. Histologically, all adenomas had a uniform pattern characterized by cords of large columnar cells forming palisades and pseudoacini separated by a delicate fibrovascular stroma. Immunostaining of adenomas derived from the pars intermedia was similar to that of non-neoplastic equine pars intermedia. An immunocytochemical evaluation revealed a diffuse, strong cytoplasmic reaction for POMC, a moderate to strong reaction for alpha-MSH and beta-END, a weak reaction for ACTH, and negative immunostaining for prolactin, GFAP, and neuron specific enolase in the adenomas. The unique clinicopathologic syndrome that develops in horses with pituitary adenomas appears to be the result of an over-production of POMC-derived peptides in addition to space-occupying effects resulting in dysfunction of the hypothalamus and neurohypophysis.

HBcAg identification in the placental cytotypes of symptom-free HBsAg-carrier mothers: A study with the immunoperoxidase method

In this study the presence of HBcAg in placental tissue of symptom-free HBsAg-carrier mothers has been determined by the immunoperoxidase technique. The presence of HBcAg in the major placental cytotypes was mostly limited to the trophoblastic lineage. Moreover the activated macrophages with their strong cytoplasmic reaction to the antigen phagocytosis play a remarkable role in the immune response. Because there are continuous channels that link the human amnion through the trophoblastic lineage, including the endovascular trophoblast with maternal decidual vessels, a functional exchange system may be considered valid. This would influence the transmission of infection.