Figure 1.

Histology of TSLP transgenic mice and human cryoglobulinemic MPGN. Glomeruli from human cryoglobulinemic MPGN (A and C) and from TSLP transgenic mice (B and D) show a range of morphologic features, including intraluminal as well as mesangial cryoglobulin deposits (arrows, A and B), mesangial expansion and increased cellularity (A through D), and splitting of basement membranes (* in A, B, and C). In both humans and mice, the deposition of cryoglobulins can be histologically inapparent, and in these cases, the association of the MPGN with cryoglobulinemia is determined only by serologic evidence of cryoglobulins. Influx of monocytes, common but not invariably so in both humans and mice, is prominent in the capillaries and probably also in mesangial regions in these examples of human and murine MPGN (C and D, respectively) and confirmed by monocyte-specific immunohistochemical labeling.