INTRODUCTION: Adiponectin (also called ACRP30, GBP28 and apM1) is a hormone exclusively expressed from adipose tissue 1. Many studies demonstrate that adiponectin has direct anti-diabetic, anti-atherogenic and anti-inflammatory functions. Adiponectin can increase insulin sensitivity of skeletal muscle 2, attenuate hepatic lipogenesis 3 and gluconeogenesis 4, regulate NO production in endothelial cells 5, inhibit proliefeartion of smooth muscle cells 6 and prevent lipid accumulation of macrophage cells 7. In the circulation, adiponectin is present as three different oligomeric complexes, including the high molecular weight (HMW), the middle molecular weight (MMW, also called hexamer) and low molecular weigh (MMW, also called trimer) forms 8. Different oligomeric complex of adiponectin activates different signaling pathways and exerts distinct functions. Trimeric form of adiponectin was expressed in HEK293 cells stably transfected with pchAd-Fvector encoding FLAG epitope-tagged human adiponectin. Recombinant adiponectin (Trimeric form) was purified using anti-FLAG M2 affinity gel (Sigma-Aldrich) and was eluted with FLAG peptide. FLAG peptides were removed by an extensive wash with an excessive volume of saline. Highly sensitive matrix-assisted laser desorption/ionization time of flight (MALDI-TOF) mass-spectrometric analysis confirmed that FLAG peptide was not detectable in the protein solution.

SPECIFICITY: The cystenine 39 was replaced with alanine (C39A) 9. hAd-C39A can only form trimer, but not hexamer or HMW form.

SOURCE: HEK293 (Human embryonic kidney cell line)

PURITY: Greater than 95%

FORMULATION: Sterile filtered and lyophilized from 0.5 mg/ml in 0.05 M phosphate buffer, 0.05 M NaCl, pH 7.2.

SOLUBILITY:Add 0.2 ml of deionized water and let the lyophilized pellet dissolve completely.

STABILITY: The lyophilized protein remains stable until the expiry date when stored at -20°C.

ACTIVITY: ED50= 3-8.5 μg/mL, as determined by its ability to inhibit proliferation of HASMCs induced by HB EGF.