Immunoelectronmicroscopic Profile of Intracytoplasmic Immunoglobulins in B Non Hodgkin's Malignant Lymphomas: Comparison with the Normal Pattern of B Lymphoid Cells*

Summary An immunoelectronmicroscopic method using Fab fragment of anti human IgG (H + L) has been employed to study the localization of cytoplasmic immunoglobulins in the tumoral cells of 12 B non Hodgkin's malignant lymphomas (B-M.L.). A comparison with normal homologous B lymphoid cells was performed on 10 non tumoral reactive lymph nodes. Immunostaining was observed in PNC, RER and Golgi complex. The criterions of differentiation were discussed in the different B-M.L.. Because of a granular hyaloplasmic immunostaining in normal and tumoral centroblasts and immunoblasts, monospecific antibodies against gamma, mu, alpha heavy chains were used to rule out a non specific uptake. Presence of mu heavy chain was discussed as an argument for immunoglobulin free ribosomal synthesis.