Figure 5.

Morphological and immunophenotypic plasma cell engagement of Myd88^L252P tumors. Hematein eosin morphological aspect (A–J) and intracytoplasmic Ig labeling (K–O) of Cd19^Cre and Myd88^L252P spleens: one 16-31 week-old Cd19^Cre (A, F, K), one ≥ 32 week-old Cd19^Cre (B, G, L) and three Myd88^L252P (C, H, M) for Normal group, (D, I, N) for Hyper Ig group and E, J, O for Peak group) mice are shown. Panels (A–E) at low magnification, Myd88^L252P tumors often exhibited a nodular pattern (C–E). Panels (F–J): at high magnification, most Myd88^L252P tumors had small B-cell aspects with marked lymphoplasmacytic engagement (panels H–J). Panels (K–O) Myd88^L252P tumors with a lymphoplasmacytic aspect exhibited marked plasma cell differentiation as revealed by the presence of intracytoplasmic Ig in numerous cells (arrows) with various labeling intensities (M–O).