Monoclonal antibodies recognizing CD5, CD10 and CD23 in formalin-fixed, paraffin-embedded tissue: production and assessment of their value in the diagnosis of small B-cell lymphoma

Aims: Assessment of the expression of antigens CD5, CD10 and CD23 can be of value in the differential diagnosis of small B-cell lymphoma. Correct subc lassification is important since optimal treatment regimes differ between t he subtypes. The aim of this study was to generate monoclonal antibodies re cognizing these antigens in paraffin-embedded tissue and to assess their ef ficacy using a panel of cases of small B-cell lymphoma of various subtypes. Methods and results: For each antibody synthetic recombinant protein and co nventional murine hybridoma technology was employed. Monoclonal antibodies effective in formalin-fixed, paraffin-embedded tissue were successfully gen erated, designated NCL-CD5-4C7, NCL-CD10-270 and NCL-CD23-1B12. respectivel y. A series of 58 cases of small B-cell lymphoma including examples of each subtype (lymphocytic, follicle centre cell, mantle cell, marginal zone and lymphoplasmacytoid) was assembled and immunostaining for the respective an tigens carried out using the monoclonal antibodies produced. Our results in dicate that the antibodies are specific for their respective antigens and g ive the predicted phenotypic profile in the small B-cell lymphoma subtypes. Conclusions: These novel monoclonal antibodies may be of value in routine d iagnostic practice.