Immunohistologic analysis of the renal distribution of type IV collagen chains in Alport syndrome

The analysis was carried out in (A-D) control, X-linked (E, F) male and (G, H) female Alport syndrome patients and (I-L) patients with autosomal recessive Alport syndrome, using antibodies to α1(IV) (A, E, I), α3(IV) (B, F, J), or α5(IV) (C, G, K, L) chains. Double labeling was made with anti-α2(IV) in red and anti-α5(IV) in green (D, H). In control kidney, the α1(IV) chain is present in the mesangial matrix, Bowman's capsule, and the extraglomerular basement membranes (A). The α3(IV) and α5(IV) chains are distributed within the GBM (B and C, respectively). The Bowman's capsule is strongly α5(IV)-positive (C). In X-linked Alport syndrome, no α3(IV) expression was detected in a male patient (id for α4-α5) (F), whereas the distribution is segmental in a female patient (G). In autosomal recessive Alport syndrome, no α3(IV)-α5(IV) labeling is detected in the GBM (J), whereas α5(IV) is expressed in Bowman's capsule (K) and the basement membranes of the collecting ducts (L). In both types of Alport syndrome, α1(IV) is diffusely expressed in the GBM (E, I).