vIL-6 mice display characteristics of plasma-cell type MCD, including splenomegaly, lymphadenopathy, lymph node vascular proliferation and plasmacytosis, and hypergammaglobulinemia. (A) Splenomegaly in vIL-6tg2 mice. Top panel: Photograph of a representative wild-type and vIL-6tg2 mouse spleen. Bottom panel: Average ratio of spleen to body weight determined from 15-week-old wild-type (n = 7) and vIL-6tg2 (n = 10) mice. (B) Lymphadenopathy in vIL-6tg2 mice. Top panel: Photographs of PLNs from 3 independent wild-type and vIL-6tg2 mice. Bottom panel: Averaged weights of inguinal lymph nodes from 15-week-old wild-type (n = 7) and vIL-6tg2 (n = 10) mice (based on the sum of the weight of both nodes per mouse). (C) H&E-stained lymph node of a representative vIL-6tg2 mouse demonstrating interfollicular vascular proliferation (20-fold magnification). Blood vessels are marked by arrows. (D) Giemsa staining from the same vIL-6tg2 lymph node revealing plasmacytosis (20-fold magnification). A cluster of mature plasma cells (encircled) is filling the sinusoids. (E) Hypergammaglobulinemia in vIL-6tg2 mice. Average relative serum IgG levels are shown from 15-week-old wild-type (n = 7) and vIL-6tg2 (n = 10) mice, as measured by ELISA. Error bars represent SD. *P ≤ .01. **P ≤ .001.
