Fig. 1

Detection of serum adiponectin isoforms with monoclonal antibodies (mAbs) against recombinant human adiponectin. a Western blot to screen mAbs detecting different adiponectin isoforms. Human serum was loaded into each lane of the gel and resolved by polyacrylamide gel electrophoresis (PAGE) and then transferred to a membrane. Each lane of the membrane was then separately cut and incubated with each mAb from hybridoma culture supernatant. After the secondary antibody was probed, the cut membrane was combined to form one sheet and developed with ECL solution. Eleven different mAbs from culture supernatant were tested to investigate their recognition patterns of adiponectin isoforms in serum. The mAb KH7–33, in lane 3, was selected as a representative recognizing only the middle molecular weight (MMW) isoform of adiponectin. The mAb KH7–41, in lane 4, was selected as a representative recognizing both the MMW and low molecular weight (LMW) isoforms of adiponectin. The mAb KH4–8, in lane 8, was selected as a representative mAb recognizing both the MMW and HMW isoforms of adiponectin. b Comparison of the mAb recognition patterns of adiponectin isoforms in human, mouse, and rat sera by Western blot. Human, mouse, and rat sera were separated by sodium dodecyl sulfate–PAGE. All three mAbs (KH7–33, KH7–41, and KH4–8) recognized the rat and mouse adiponectin MMW isoform. Lane 1, KH7–41; lane 2, KH7–33; lane 3, KH4–8; lane 4, commercial antibody against human adiponectin (Boster Immunoleader cat. no. PB9001) or mouse/rat adiponectin (Boster Immunoleader cat. no. PB9011). Mouse and rat serum were obtained via heart puncture of male BALB/c mice and Sprague Dawley rats (8 weeks old), respectively. Human serum was obtained from a male volunteer (55 years old)