Fig. 4.

Determination of IgG subclasses of antibodies against α-enolase in sera from patients with primary and secondary MN. One microgram of purified α-enolase was run on SDS–PAGE gels, and transferred to each strip. The strips were incubated with sera from patients with primary MN (a–e), patients with secondary MN (f–h), and a healthy individual (i). Thereafter, they were incubated with alkaline phosphatase-conjugated anti-human IgG1 (lane 1), IgG2 (lane 2), IgG3 (lane 3), and IgG4 (lane 4). One of the strips (j) was stained with coomassie brilliant R-250. The arrowhead indicates the purified 47-kD protein band of α-enolase. Immunoreactive protein bands with lower molecular mass on panels (a) and (b) are regarded as fragments of α-enolase.