Pleural mesothelioma in a nine-month-old dog

This paper reports on an unusual case of pleural epitheloid mesothelioma in a nine-month-old male, mixed breed dog. The dog was presented in-extremis and, on post mortem examination, multiple, exophytic, frequently pedunculated, yellowish-red, soft to firm masses ranging from 3 mm to 6 cm in diameter were diffusely distributed over, and attached to, the pericardial and parietal pleural surfaces. Microscopically, these masses consisted of round to partially polygonalshaped, anaplastic cells with minimal cytoplasm and hyperchromatic nuclei covering papillomatous projections or as part of more densely cellular masses. A supporting fibrovascular stroma and mitotic figures were also evident. Constituent tumour cells were labeled positively with antibodies against both vimentin and cytokeratin. In contrast, the same cells exhibited equivocal labeling with an antibody directed against calretinin antigen and did not label with antibodies against carcinoembryonic antigen (CEA) and milk fat globule-related antigen (MFGRA). Such tumours are rare in dogs, particularly in such a young animal

A Novel Redox Method for Rapid Production of Functional Bi-Specific Antibodies For Use in Early Pilot Studies

We demonstrate here a rapid alternative method for the production of functional bi-specific antibodies using the mild reducing agent 2-mercaptoethanesulfonic acid sodium salt (MESNA). Following reduction of a mixture of two monoclonal antibodies with MESNA to break inter heavy chain bonds, this solution is dialysed under oxidising conditions and antibodies are allowed to reform. During this reaction a mixture of antibodies is formed, including parental antibodies and bi-specific antibody. Bi-specific antibodies are purified over two sequential affinity columns. Following purification, bi-specificity of antibodies is determined in enzyme-linked immunosorbent assays and by flow cytometry. Using this redox method we have been successful in producing hybrid and same-species bi-specific antibodies in a time frame of 6–10 working days, making this production method a time saving alternative to the time-consuming traditional heterohybridoma technology for the production of bi-specific antibodies for use in early pilot studies. The use of both rat and mouse IgG antibodies forming a rat/mouse bi-specific antibody as well as producing a pure mouse bi-specific antibody and a pure rat bi-specific antibody demonstrates the flexibility of this production method

The expression of intermediate filaments and mam-6 antigen in relation to the degree of morphologic differentiation of carcinoma of the head and neck: diagnostic implications

In this study, the immunoreactivity of several cytokeratin antibodies; 115 D8, a monoclonal antibody against MAM-6, an epithelial membrane antigen; and two vimentin antibodies, is examined in relation to the degree of morphologic differentiation in carcinomas of the head and neck. The results indicate that a relationship exists between the degree of morphologic differentiation and the expression of cytokeratin, MAM-6, and vimentin, as detected by polyclonal antikeratin, 115 D8 and anti-vimentin. Expression of cytokeratin and MAM-6 is reversely related to vimentin. Polyclonal anti-keratin; CAM 5.2, a monoclonal antibody against cytokeratin 8, 18 and 19; and 115 D8, used in combination, were still able to identify the epithelial nature of undifferentiated/spindle cells. Since these immunohistochemical markers precede light microscopic detectable signs of epithelial differentiation, they can be used for the identification of the epithelial nature of undifferentiated/spindle tumors of the head and nec

Diagnostic application of panels of antibodies in mucosal melanomas of the head and neck

This article describes the use of panels of antibodies in the histopathologic diagnosis of ten malignant melanomas arising in the mucosa of the head and neck. The immunohistochemistry analysis was performed in a step-by-step manner. In the first step a panel of antibodies discriminating between carcinoma, malignant lymphoma, and melanoma was used. Staining with antivimentin and the melanoma-associated antigen, moAb NKI/C-3, was found to occur in all cases. The NKI/C-3 stained nine of 10 specimens from the first biopsy. Anti-S-100 protein, anti-HMW-MAA, and NKI-beteb was used as a panel in the second step. These stained ten of ten, five of six, and seven of seven cases, respectively. The diagnosis for melanin was confirmed by extensive sampling and a diligent search for melanin and (pre)melanosomes in different biopsy and surgical specimens. These results indicate that a step-wise application of immunohistochemistry is a very useful tool in the diagnosis of mucosal melanoma of the head and nec