Chordoma: an immunohistologic study

Fourteen chordomas, five myxoid chondrosarcomas, and 15 chondroid tumors (four mesenchymal and 11 conventional chondrosarcomas) were stained for cytokeratin, S-100 protein, carcinoembryonic antigen (CEA), and vimentin. The epithelial markers stained 93 per cent of the chordomas, whereas none of the tumors of other types showed any staining. Sixty-four per cent of the chordomas, 20 per cent of the myxoid chondrosarcomas, and 87 per cent of the other chondroid tumors were positive for S-100 protein. All of the tumors were positive for vimentin. Three of the 14 chordomas were positive for CEA. The present study confirms the utility of these markers in the differential diagnosis of chordoma and tumors with similar histologic characteristics.     

Retinal ependymoma: an immunohistologic and ultrastructural study

Glial tumors of the retina are rare. Most are syndrome associated and include pilocytic astrocytoma in neurofibromatosis type 1 and subependymal giant cell astrocytoma in tuberous sclerosis complex. Acquired, more conventional, diffuse astrocytomas are less frequent. Ependymoma is exquisitely rare. Herein, we report the clinicopathologic features of the second case of retinal ependymoma. The tumor was sporadic in occurrence and unilateral, low grade, and of cellular type. Its chronic course and large size prompted an initial pathologic diagnosis of "massive retinal gliosis." The literature regarding retinal glial neoplasia including ependymoma as well as the so-called massive retinal gliosis is discussed.     

Allergic fungal sinusitis: an immunohistologic analysis

BACKGROUND: Allergic fungal sinusitis is a noninvasive form of fungal sinusitis that has recently been delineated as a distinct clinicopathologic entity. It is increasingly recognized as a cause of chronic sinusitis, with the primary causative agents being members of the Dematiaceae fungus family. Although its immunopathogenesis has not been elucidated, the eosinophil is a prominent inflammatory cell on histologic examination. OBJECTIVE: We sought to characterize the involvement of eosinophils in sinus tissue and accompanying mucin from patients with allergic fungal sinusitis. As a comparison, neutrophil and mast cell involvement was also evaluated in the same group of patients. METHODS: Tissue specimens from 8 patients with allergic fungal sinusitis, along with 8 nasal polyp specimens from patients without allergic fungal sinusitis, were stained by using indirect immunofluorescence for eosinophil granule major basic protein (MBP). Neutrophil elastase and mast cell tryptase staining was also performed on the same allergic fungal sinusitis and nasal polyp tissues. RESULTS: MBP was diffusely localized within the mucin, showing intense staining at the periphery and variable staining of degenerated cell clusters throughout. Extracellular MBP in the mucin was strikingly greater than intact eosinophil staining. Diffuse extracellular neutrophil elastase was also present in the mucin. Mucinous areas showed no tryptase localization. Adjacent nonmucinous areas of respiratory mucosa showed predominantly cellular staining with eosinophil MBP, neutrophil elastase, and mast cell tryptase. MBP staining of nasal polyps showed a predominantly cellular pattern with focal areas of extracellular deposition. CONCLUSIONS: Given the known toxicities of eosinophil granule MBP and neutrophil elastase, their extracellular presence supports the contribution of these proteins in the pathogenesis of allergic fungal sinusitis and further indicates that eosinophil and neutrophil activation occurs in the disease.     

Expression of the PIP/GCDFP-15 gene and survival in breast cancer

Expression of the PIP/GCDFP-15 gene was determined by measuring PIP/GCDFP-15-mRNA in breast carcinomas of 91 patients. The patients were followed-up for an average of 47 months after initial diagnosis and treatment of the disease. There were no deaths in the group of 14 patients with tumours of high PIP/GCDFP-15-mRNA levels, while 16 of 77 patients of the group with low PIP/GCDFP-15-mRNA tumour levels died. A similar advantage for high PIP/GCDFP-mRNA expression was observed with regard to disease free survival.     

Refinement of immunohistologic parameters for Her2/neu scoring validation by FISH and CISH.

The conventional method of scoring Her2/neu immunostaining is recognized to result in a high false-positive rate among 2+ cases when compared with results obtained with fluorescence in situ hybridization (FISH); however, costs and convenience dictates that immunohistochemistry remains the screening test for Her2/neu status in patients with breast cancer. We describe refined criteria for scoring of Her2/neu on the basis of anatomic localization rather than the subjective assessment of intensity. The presence of a circumferential tram track pattern that results from the staining of apposing cell membranes in >25% of the tumor cells was necessary for a 3+ score (Her2/neu overexpressed) and the presence of the tram track pattern in <25% was scored 2+ (equivocal); granular and fragmented membrane staining was scored 1+ (negative). The tram track pattern of Her2/neu overexpression showed 100% concordance with gene amplification. FISH and CISH testing in selected cases from the other categories validated the revised scoring method. These criteria reduced the numbers of equivocal staining cases that required FISH testing.     

PIP/GCDFP-15 gene expression and apocrine differentiation in carcinomas of the breast

The frequency and the significance of apocrine differentiation in carcinomas of the breast are uncertain, because of the lack of reliable and reproducible criteria for morphological diagnosis. The 15 kDa glycoprotein of cystic breast disease (GCDFP-15) is regarded as a specific functional marker of apocrine cells. Expression of the prolactin-inducible protein (PIP)/GCDFP-15 gene was investigated by Northern blot analysis and in situ hybridization in breast cancer cell lines and in an unselected series (33 cases) of primary carcinomas of the breast. On the same cases, histological assessment of apocrine differentiation and immunocytochemical detection of GCDFP-15 were also performed and correlated with follow-up data. The presence of PIP/GCDFP-15 mRNA was a feature of a relatively high number of cases, but was incompletely correlated with histological and immunocytochemical evidences of apocrine differentiation. Expression of the PIP/GCDFP-15 gene was significantly associated with relapse-free survival, and may represent a novel variable of functional and prognostic relevance.Work supported by grants from Associazione Italiana per la Ricerca ca sul Cancro (AIRC) (Milan, Italy), Consiglio Nazionale Ricerche (CNR, grant N. 93.02125.PF39), Ministero dell' Universita' e della Ricerca Scientifica e Tecnologica (MURST), Rome, Italy.     

Screening for atrial fibrillation: sensitivity and specificity of a new methodology

There is no comprehensive screening programme for atrial fibrillation (AF) in either the UK or the US. This paper describes a simple new technology that could contribute to such a universal screening programme. The work analyses the utility of a new instrument that uses plethysmographic analysis of finger-tip pulse in the detection of AF. Comparative analysis of the instrument with the ‘gold-standard’ diagnostic method was undertaken in 594 patients. With the instrument set to detect all cases of AF (100% sensitivity), a specificity of 91.9% (8.1% false positives) was obtained. The authors conclude that the instrument described provides an accurate and reliable screening tool for AF, filling a gap in the current process of early detection in the community.     

Murine monoclonal anti-avidin antibodies enhance the sensitivity of avidin-biotin immunoassays and immunohistologic staining

To improve the sensitivity of conventional immunoassay methods using avidin-biotin-enzyme complex reagents, we have developed several murine monoclonal antibodies to the egg white avidin glycoprotein. These anti-avidin antibodies enhance the sensitivity of avidin-biotin immunoassays by selectively enlarging the avidin-biotin-enzyme complex through bridging avidin to a second layer of avidin-biotin-enzyme complex, thereby increasing the signal from substrate conversion. Six hybridomas producing murine monoclonal antibodies which bind avidin-biotin-enzyme complexes were isolated and cloned. Two of these anti-avidin antibodies, WC19.10 and WC19.7, have been shown to produce a four-fold enhancement of signal obtained in avidin-biotin-enzyme ELISAs and qualitative enhancement of immunohistologic staining procedures.     

Bulbectomy and sensitivity to estrogen: Anatomical and functional specificity

In order to clarify the influence of the olfactory system on female sexual behavior, ovariectomized rats were given sham operations (SHAM), total bilateral olfactory bulbectomy (TBULBX), partial bulbectomy (PBULBX), anterior olfactory nucleus lesions (AON) or accessory olfactory bulb lesions (AOB), and tested for lordosis behavior. Only TBULBX resulted in increased sensitivity to estradiol benzoate (EB) in that lordosis quotients (LQ) were increased and rejection behavior decreased following administration of 2, 4 or 8 μg EB/kg/day for 3 days. Only TBULBX group rats were anosmic on 2 postoperative tests. TBULBX group rats showed very mild hyperresponsiveness on an emotionality test. Effects of TBULBX on LQ are not due to general sensory hyperresponsiveness or EB-induced hyperresponsiveness since no differences in the quality of lordosis occurred, and no differences occurred in latency to paw-lift on hot plate tests with or without EB. Heightened EB sensitivity in the TBULBX group is not due to adrenal steroids since following adrenalectomy and 8 μg EB/kg treatment, TBULBX group LQ scores were still elevated relative to those of SHAM controls. The LQ scores of PBULBX group rats were intermediate to those of SHAM and TBULBX group rats. Bulbectomy-induced alterations in sensitivity to EB as measured by the LQ do not appear to be due to alterations in “arousal” mechanisms in general. While deficits in olfactory perception might exacerbate the effect, it is unlikely that anosmia per se is sufficient to induce major alterations in the degree of sexual receptivity following EB. The magnitude of behavioral effects of bulbectomy on EB sensitivity may be related, to some extent, to the amount of bulb tissue removed. It is possible that bulbectomy may enhance behavioral sensitivity to EB by disrupting biochemical responses to EB in limbic system structures which normally exert an inhibitory influence over sexual receptivity.     

The Pediatric Early Elementary Examination: sensitivity and specificity.

Evaluated the sensitivity and specificity of the Pediatric Early Elementary Examination (PEEX), a test designed to identify children at risk for learning problems. Using a sample of 299 seven- to nine-year-old "disadvantaged" children, the number of "areas of concern" identified by the PEEX and a school record indicating whether a child was receiving special educational services were used to compute test sensitivity and specificity. For two areas of concern, the sensitivity was 76.9% and specificity was 59.9%. The findings indicate that the PEEX correctly identified only 64.3% of children receiving special educational services. The test has a high rate of false positives while still failing to identify 6-7.5% of the children receiving special education services. Other issues relating to the utility of the PEEX are discussed.     

Understanding specificity and sensitivity of T-cell recognition

The response of T cells to antigen shows an amazing degree of both sensitivity and specificity, with a cell responding to 1-10 peptide-MHC complexes and being sensitive to single amino acid substitutions. Kinetic proofreading or feedback pathways achieve specificity at the level of the receptor, whereas serial engagement of receptors by ligand molecules enhances sensitivity. Crosstalk between receptors, integration of signals and/or tuning of responses is important at the level of the cell. Induction of anergic or regulatory cells by suboptimal stimuli prevents cell activation by multiple encounters with weak ligands. Thus, for optimal sensitivity and specificity, it is necessary to have mechanisms that operate at the level of the receptor, the cell and finally, the population of responding cells.     

The lymphocyte transformation test for the diagnosis of drug allergy: sensitivity and specificity

Background The diagnosis of a drag allergy is mainly based upon a very detailed history and the clinical findings. In addition, several in vitro or in vivo tests can be performed to demonstrate a sensitization to a certain drug. One of the in vitro tests is the lymphocyte transformation test (LTT), which can reveal a sensitization of T-cells by an enhanced proliferative response of peripheral blood mononuclear cells to a certain drag. Objective To evaluate the sensitivity and specificity of the LTT, 923 case histories of patients with suspected drag allergy in whom a LTT was performed were retrospectively analysed. Methods Based on the history and provocation tests, the probability (P) of a drag allergy was estimated to be >0.9, 0.5–0.9, 0.1–0.5 or <0.1, and was put in relation to a positive or negative LTT. Results Seventy-eight of 100 patients with a very likely drag allergy (P<0.9) had a positive LTT, which indicates a sensitivity of 78%. If allergies to betalactam-antibiotics were analysed separately, the sensitivity was 74.4%. Fifteen of 102 patients where a classical drag allergy could be excluded (P<0.1), had nevertheless a positive LTT (specificity thus 85%). The majority of these cases were classified as so-called pseudoallergic reaction to NSAIDs. Patients with a clear history and clinical findings for a cotrimoxazole-related allergy, all had a positive LTT (6/6), and in patients who reacted to drags containing proteins, sensitization could be demonstrated as well (i.e. hen's egg lysozyme, 7/7). In 632 of the 923 cases, skin tests were also performed (scratch and/or epicutaneous), for which we found a lower sensitivity than for the LTT (64%), while the specificity was the same (85%). Conclusion Although our data are somewhat biased by the high number of penicillin allergies and cannot be generalized to drag allergies caused by other compounds, we conclude that the LTT is a useful diagnostic test in drag allergies, able to support the diagnosis of a drag allergy and to pinpoint the relevant drag.     

The gel test: sensitivity and specificity for unexpected antibodies to blood group antigens

The recently FDA-licensed anti-IgG gel test for pretransfusion antibody detection requires crossover validation before implementation. Six hundred coded samples sent for routine pretransfusion tests were used to compare GEL (ID-MTS, Ortho Diagnostic Systems Inc., Raritan, NJ) with L?w and Messeter's low-ionic-strength saline (LISS). There were 456 GEL-LISS-, 97 GEL+LISS+, 45 GEL-LISS+, and 2 GEL+LISS- tests. The 144 positive tests involved 157 antibodies; 67 of these (cold auto, anti-M, -Le, etc.) were considered harmless with respect to transfusion management. GEL-LISS+ tests included seven samples containing potentially significant antibodies (assumed from specificity): anti-K(4), -Jka, -Fyb, and -S. Two potentially significant antibodies (anti- C and -D) were GEL+LISS-. Sensitivity and specificity for potentially significant antibodies were 92% and 96% for GEL, and 98% and 90% for LISS, respectively. The seven GEL-LISS+ samples associated with potentially significant antibodies were from six patients. Five of these antibodies, all detected in immune-suppressed patients, reacted predominantly as agglutinins in LISS. None of these seven antibodies were detected reliably by polyethylene glycol and LISS-additive tube methods. In light of the immune status of the patients with GEL-LISS+ agglutinins with specificity normally considered potentially significant, and because other valid methods did not detect these antibodies, their clinical importance is questionable. Excluding these questionable antibodies, GEL has the same sensitivity and better specificity than LISS. GEL is a valid method for pretransfusion antibody detection.     

A micro solid-phase radioimmunoassay for detection of herpesvirus type-specific antibody: specificity and sensitivity

The specificity and sensitivity of a micro solid-phase radioimmunoassay (micro-SPRIA) that detects type-specific IgG antibody to herpes simplex virus types 1 and 2 (HSV1 and HSV2) were evaluated. Glycoproteins VP123 (molecular weight, 123,000) of HSV1 and VP119 (molecular weight, 119,000) of HSV2 were found to display the greatest degree of antigenic type-specificity of several HSV antigens tested with the micro-SPRIA technique. When testing a group of sera, negative for anti-HSV antibodies by microneutralization, in the micro-SPRIA, a range of negative reactivities was noted, suggesting that cut-points should be determined for each antigen preparation. The micro-SPRIA detected appropriate antibody activity in patients with recurrent infection and a marked agreement was noted in comparison to detection of anti-HSV antibodies measured with the microneutralization test. The type-specificity of the micro-SPRIA was substantiated by the independence of test results using VP119 and VP123 antigens for a random group of positive sera. The assay is rapid, specific, and sensitive and allows the testing of multiple serum samples with a standardized set of reagents.     

WEHI 164 subclone 13 assay for TNF: sensitivity, specificity, and reliability

Tumor necrosis factor alpha (TNF) is a peptide monokine involved in a number of immune reactions. To further understand the role of TNF in disease states it is critical to have an inexpensive, yet sensitive and specific assay. Additionally, the effects of prostaglandin E2 (PGE2), dexamethasone (dex), and cyclosporine A (CsA) on TNF gene expression have been studied, although little is known of the effects these compounds have on TNF containing samples. The aim of this study is to determine the sensitivity and specificity of a highly sensitive cell line to the actions of TNF, and to elucidate parameters which affect the stability of TNF in biological fluids. Dex and PGE2 at concentrations of 10(-5), 10(-7), and 10(-9) M, were shown not to effect the WEHI assay, and neither did CsA (10 ng/ml-1 ug/ml). The cells were not lysed by recombinant murine IL-1 alpha or beta, human recombinant IL-1 alpha or beta, human recombinant IL-2 or human recombinant IL-6 at concentrations ranging from 0.02 pg/ml to 1.0 ug/ml, or murine gamma-IFN from 100 pg/ml to 10 ng/ml. TNF containing samples with 1%-10% fetal calf serum maintained their cytolytic activity even after three freeze-thaw cycles. Serum samples did not lose any cytolytic activity with up to 11 cycles of freezing and thawing whereas, tissue culture media, containing TNF, lost significant activity with freeze-thawing. The WEHI assay has successfully detected cytolytic activity from lipopolysaccharide stimulated specimens from a number of different species. These data show the utility of this highly sensitive and specific assay. Furthermore, the WEHI assay showed a high degree of reproducibility in repeated assays.     

Immunoassays of amphetamines: immunogen structure vs antibody specificity.

Various immunoassays have been developed for the detection of amphetamines. These have varying degrees of cross-reactivity to other drug and food components. Information on the immunogen structures used, and the specificities of the antibodies obtained, have allowed formulation of a "structure-specificity" pattern delineated on the basis of immunochemistry and stereochemistry. The 'structure-specificity' relationship should be useful to future developments of these immunoassays. Specifically, immunoassays intended to detect either amphetamine or methamphetamine with minimal cross-reaction, should employ immunogens with amphetamine (or methamphetamine) derivatized via the para position of the phenyl ring. Such assays should show minimal cross-reaction with other secondary (or tertiary) amines but should strongly cross-react with phenyl ring substituted analogs. On the other hand, assays intended for detection of both amphetamine and methamphetamine should employ amphetamine (rather than methamphetamine) derivatized via its amino group as an immunogen. Such assays should show minimal cross-reaction with other tertiary amines and phenyl-substituted amphetamine/methamphetamine.     

Recurrent "syncytial variant" of Hodgkin's disease: an immunohistologic diagnosis

A case of recurrent Hodgkin's disease of the "sarcomatoid" or "syncytial variant" type was seen that occurred as an extension from the mediastinum to a previously uninvolved extranodal site (breast) and pericardium after treatment of classical nodular sclerosing Hodgkin's disease based in the lymph nodes. This histologic variant was composed of sheets of large, undifferentiated neoplastic cells with few, if any, diagnostic features of nodular sclerosing Hodgkin's disease. For this reason, the differential diagnosis of this variant was difficult and included non-Hodgkin's lymphoma (peripheral T-cell lymphoma), Ki-1-positive lymphoma, medullary carcinoma, metastatic carcinoma, melanoma, and granulocytic sarcoma. Immunologic analysis by immunoperoxidase technique showed a phenotype consistent with "syncytial variant" Hodgkin's disease: Leu-M1+, Ki-1+, IL-2+, HLA-DR+, T11-, pan B-, K-, lambda-, cytokeratin-, S-100-, muramidase-.     

Direct agglutination test for diagnosis of Toxoplasma infection: method for increasing sensitivity and specificity.

A method that increases the sensitivity and specificity of the direct agglutination (AG) test for diagnosis of Toxoplasma gondii infection is described. Qualitative results in the Sabin-Feldman dye test (DT) and AG test were in excellent agreement (98%). Differences in titers between these two tests often related to the length of time the individual was infected. The AG test titer was most often lower than the DT titer during acute (recent) infection; the AG test titer was most often higher than the DT titer in older or chronic infection. If the AG test antigen described here can be made available, the AG test would be ideal for use as a screening test and would provide a simple and inexpensive means for the surveillance of seronegative women during pregnancy and for detection of seroconversions.