We generated a murine monoclonal antibody (B28p) detecting an antigenic determinant shared by the immunoglobulin superfamily receptor translocation-associated 1 (IRTA1) receptor (the immunogen used to raise B28p) and an unrelated 28-kDa protein that was subsequently subjected to extensive characterization. The expression of the 28-kDa protein in normal lymphohematopoietic tissues was restricted to B cells and plasma cells and clearly differed from that expected for IRTA1 (selectively expressed by mucosa-associated lymphoid tissue [MALT] marginal zone B cells). Two-dimensional polyacrylamide gel electrophoresis (2D-PAGE)/mass-spectrometry analysis identified the 28-kDa protein as human tumor protein D52 (TPD52), whose expression had been previously described only in normal and neoplastic epithelia. Specific B28p reactivity with TPD52 was confirmed by immunostaining/immunoblotting of TPD52-transfected cells. TPD52 expression pattern in normal and neoplastic B cells was unique. In fact, unlike other B-cell molecules (paired box 5 [PAX5], CD19, CD79a, CD20, CD22), which are down-regulated during differentiation from B cells to plasma cells, TPD52 expression reached its maximum levels at the plasma cell stage. In the Thiel myeloma cell line, TPD52 bound to annexin VI in a Ca2+-dependent manner, suggesting that these molecules may act in concert to regulate secretory processes in plasma cells, similarly to what was observed in pancreatic acinar cells. Finally, the anti-TPD52 monoclonal antibody served as a valuable tool for the diagnosis of B-cell malignancies.
|Titolo:||Tumor protein D52 (TPD52): A novel B-cell/plasma-cell molecule with unique expression pattern and Ca2+-dependent association with annexin VI|
|Parole Chiave:||Reed-sternberg cells; plasma-cells; lymphoblastic lymphoma; monoclonal-antibodies; breast-carcinoma; acinar-cells; copy number; gene family; identification; hodgkin|
|Settore Scientifico Disciplinare:||Settore MED/15 - Malattie del Sangue|
|Data di pubblicazione:||2005|
|Digital Object Identifier (DOI):||10.1182/blood-2004-07-2630|
|Appare nelle tipologie:||01 - Articolo su periodico|