Characterization of Monoclonal Antibodies to turbot (Scophthalmus maximus L.)

Monoclonal antibodies (mAbs) can be used in several applications, v.g in the aquaculture field. In attempt to study the immune system of the turbot fish, we wanted to develop mAbsdirected against turbot’s lymphocytes, mainly T cells. BALB/c mice were immunized with turbot thymic cells and mouse splenocytes were fused with mouse myeloma cells to genera-te hybridomas. The screening of secretory hybridomas was first performed by ELISA. Then, specificity of different monoclonal antibodies was determined by using immunohistoche-mical and immunofluorescence methods and, on the basis on their reactivity with cells from lymphoid tissues of turbot, three antibodies called RoA3, RoA4 and RoD4 were selected.RoA3 positively reacted with the membrane components of cells resembling to thymocytes, RoA4 stained cells with extended cytoplasmic processes, compatible with reticular cells.In the case of RoD4 mAb, it stains large cells mainly in the medullar zone of the thymus, compatible with macrophages and reticular cells. Flow cytometry studies showed its specifici-ty for thymic cells (no reaction with spleen or pronephros cells), further confirmed by western blot, indicating that RoD4 mAb recognizes a specific protein of 130-135 kD only onthymic tissue