EXPRESSION OF CARBOHYDRATE ANTIGENS, P80(NPM ALK), CYTOTOXIC CELL-ASSOCIATED ANTIGENS, AND EPSTEIN-BARR-VIRUS GENE-PRODUCTS IN ANAPLASTIC LARGE-CELL LYMPHOMAS/

The expression of carbohydrate antigens, including sialyl Lewis X (SLE X) and BNH9 antigen, the nucleophosmin (NPM)-anaplastic lymphoma kinas e (ALK) fusion protein (p80(NPM/ALK)), cytotoxic cell-associated antig ens, and Epstein-Barr virus (EBV) gene products in CD30+ anaplastic la rge cell lymphoma (ALCL) was investigated by immunohistochemistry and in situ hybridization (ISH) methods. The expression of SLEX and BNH9 a ntigen in ALCL was examined using CSLEX1 and BNH9, which specifically react with SLEX and oligosaccharides (H and Y haptens), respectively. SLEX was expressed in seven of 12 ALCL and BNH9 was positive for five of 12 ALCL. With respect to the relationship between SLEX and BNH9 exp ression in ALCL, some ALCL expressed both antigens, which suggests tha t they might have an increased or preserved activity of glycosyltransf erase that is responsible for the synthesis of the type I or type II c ore sequences, although other ALCL expressed either SLEX or BNH9. To d etect p80(NPM/ALK) in ALCL, the sections were immunostained with an an ti-p80 antibody, Three of 12 ALCL expressed the NPM/ALK-encoded p80 pr otein, All three ALCL positive for p80(NPM/ALK) expressed SLEX and two of them were stained with BNH9, which raised the possibility that p80 overexpression may be involved in the aberrant expression of type I o r type II chains with varying degrees of fucosylation or sialylation, While the expression of cytotoxic cell-associated antigens such as CD8 , CD56 and T cell intercellular antigen 1 (TIA-1) in ALCL was immunohi stochemically examined, none of the 12 ALCL expressed CD56 and only on e case expressed CD8, TIA-1 was expressed in seven of 12 ALCL, Four of five BNH9-positive cases expressed TIA-1, suggesting that BNH9-positi ve cases tended to have TIA-1, In situ hybridization studies using an EBV-encoded RNA-1 (EBER-1) probe were performed on 12 ALCL to detect E BV in the lymphoma cells, EBER-1 signals were detected in the small ly mphocytes but not in the lymphoma cells of two ALCL. However, latent m embrane protein 1 immunoreactivity was found in one case, These result s appear to indicate that there is no strong association between EBV a nd ALCL.