In general, the ultrastructure of normal lymphocytes and plasma cells reflects their functional state. Similarly, in pathologic conditions, ultrastructural abnormalities may reflect specific functional derangements of the cells. The identification of some structural abnormalities may be clinically useful, even though their origin and biochemical composition is still obscure.
Zucker-Franklin D. Cellular Structure and Neoplastic in Normal and Function Lymphoid Cells. Arch Intern Med. 1975;135(1):55-60. doi:10.1001/archinte.1975.00330010057008