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M Sil

Publications and source records attributed to M Sil.

5 recordsLinked to original sources

A monoclonal antibody to a cytoskeletal protein selectively recognizing malignant neuroectodermal tumors.

Fusion of myeloma (P3X63-Ag 8.653) cells with spleen cells from BALB/c mice immunized with human neuroblastoma (SK-N-SH) cells yielded a hybridoma clone, referred to as 3XB7, with a unique pattern of reactivity to malignant neuroectodermal tumors except gliomas of low-grade malignancy. Indirect immunofluorescence staining under different conditions and Western blot analysis indicate that the 3XB7 MAb recognizes an intracellular cytoskeletal protein of M(r) 52K. Immunohistochemical studies with cryostat and paraffin-embedded sections from tumor biopsies revealed that the 3XB7 MAb specifically recognizes malignant neuroectodermal tumors and reacts negatively with other epithelial and mesenchymal tumors, e.g., carcinomas, lymphomas, and sarcomas as well as with normal adult and fetal brain tissues. Negative reaction was also observed with other small round cell tumors of childhood. Thus the 3XB7 antigen can be used for diagnosis of all stages of neuroblastomas, and its specific expression in gliomas with high-grade malignancy (grades III and IV) confer on it additional prognostic value.

Adult↗

An ELISA method for quantitation of tubulin using poly-1-lysine coated microtiter plates.

A new, sensitive and convenient ELISA method has been developed for quantitation of tubulin using poly-1-lysine (PLL) coated multiwell microtiter plates. Binding of tubulin to untreated plastic surface of microtiter plates was extremely poor. Coating of wells with PLL enhanced the binding and facilitated quantitation by ELISA. Binding of tubulin was followed by stepwise additions of rabbit anti-tubulin IgG, HRP-conjugated goat anti-rabbit IgG and colour reagent. The method has been successfully applied to quantitate the tubulin content of extracts from rat brain and liver as evident from the excellent correlation of the results with those obtained from 3H-colchicine binding assay. The detection limit is as low as 5 ng, which is relatively better than that of the previous RIA methods. The ELISA method does not involve the use of any radioactive compound and all reagents required for this assay are commercially available.

Animals↗

Comparative analysis of the membrane proteins and their specificities in neurons, protoplasmic astrocytes, and oligodendrocytes from rat brain.

Plasma membranes from neuronal perikarya (N), protoplasmic astrocytes (A) and oligodendrocytes (O) of rat brains were analysed with respect to their protein and glycoprotein contents and specificities. SDS-polyacrylamide gel electrophoresis revealed a total number of 23, 17, and 17 major proteins in N, A, and O respectively. Periodate-Schiff's staining showed that approximately 40-60% of these proteins were glycoproteins. The reactivity of these glycoproteins to Con A and WGA was also studied. Selective iodination of whole cells followed by electrophoresis and autoradiography indicated that of the major proteins, only 25% of neuronal and 60% of astroglial and oligodendroglial membrane proteins were exposed outside the cell surface. The overall results suggest that membrane proteins of each of the three cell types studied here have characteristically different internal and external markers differing in size, glycoprotein content, and reactivity of the glycoproteins to lectins.

Animals↗