Figure 2: A panel of photomicrographs of the second (allograft) renal biopsy. (a) Enlarged glomerulus with accentuated lobulation, thickening of the glomerular capillary walls (thin arrow) along with mesangial expansion and increase in mesangial and endocapillary cellularity (block arrow) (H and E ×40). (b) Another glomerulus showing capillary wall thickening, focal reduplication (thin arrow), and mesangial matrix expansion (block arrow) (periodic-acid Schiff ×40). (c) Immunofluorescence for IgG antisera showing intense granular mesangial and capillary wall staining. (d) Immunofluorescence for kappa antisera showing intense granular mesangial and capillary wall staining. (e) Immunofluorescence for lambda antisera showing no staining. (f) Immunofluorescence for IgG1, IgG2, IgG3, and IgG4 antisera showing positivity only for IgG3.