Adiponectin(ADPN) is a protein hormone that is express and secreted by adipose tissue. It's abundant in the blood circulation, About 0.01% of total human plasma protein. It plays an important role in regulating insulin sensitivity and glucose metabolism.

Human adiponectin monomer is composed of 244 amino acids, including four regions: N-terminal signal peptide, non-homologous region, collagen repeat sequence and globular carboxyl-terminal. Collagen repeat sequence has great correlation with the evolution of species.Adiponectin occurs in the blood in many subtypes, Monomer adiponectin (28kDa) is first polymerized into biologically active trimer (65 kDa) in adipocytes, and then on this basis into hexamer (150 kDa) and high molecular weight asymmetric bouquet like adiponectin (18-36 monomers, >280 kDa) and secreted into the circulating blood.The plasma adiponectin properties of normal subjects were stable, and several subtypes of adiponectin did not convert to each other.

Adiponectin is a novel predictor of early risk for type 2 diabetes.Adiponectin is a risk predictor of diabetes, unlike blood glucose and glycosylated hemoglobin,Adiponectin can be used to screen out people at high risk of diabetes with normal blood glucose but abnormal physiological metabolism. Adiponectin can dynamically reflect the level of insulin resistance of the body and is closely related to the metabolic health of individuals.

Anti-Human Adiponectin Monoclonal Antibodies

Calibration Curve

A.  Latex Enhanced Turbidimetric Immunoassay(LETIA)

The humanADPN protein reacts with the anti-humanADPN antibody coated onto latex microspheres, resulting in agglutination and increase in turbidity. The changes in absorbance are then measured using a spectrometer to quantitatively measure theADPN concentration in the samples. As shown in Figure 1, there is a significant linear correlation between the ADPN concentration and delta absorbance.

Fig.1 The calibration curve forADPN in immunoturbidimetric assay

B. Chemiluminescent Immunoassay(CLIA)

The best two-site MAB combinations have been selected for the quantitative detection ofADPN with double monoclonal antibody sandwich method,CSB-DA120AmN③ as capture antibodies and CSB-DA120AmN④ labeled with horse reddish peroxidase(HRP) as detection antibodies. The calibration curve betweenADPN concentration and relative light units is fitting by four-parameter logistic 2 model.(R =0.995)

Fig.2 The calibration curve forADPN chemiluminescent immunoassay

C. Lateral flow immunoassay (LFIA)

A set ofADPN calibrators with the concentration of 0-40 ug/mL was detected on CUSAg LFIA platform using two anti-ADPN monoclonal antibodies. The capture antibody was stripped on the nitrocellulose membrane, and the detection antibody was conjugated to fluorescent microspheres; The best selected MAb combination for the development of semi-quantitative humanADPNimmunoassays is (capture-detection):

CSB-DA120AmN③ - CSB-DA120AmN④

Fig.3 Semi-quantitative detection of ADPN protein in colloidal gold immunochromatogragph ic assay

Clinical Comparison

A. Latex Enhanced Turbidimetric Immunoassay(LETIA)

Anti-ADPN monoc lonal antibodies were evaluated by immunoturbidimetric assay in medium-scale clinical trials with random blood samples from donates (n=32). Fig.4 shows the comparison of ADPN concentrations determined via the self-made antibodies and high-quality kits. Results reveal good agreement between CUSAg immunoassays and comparison assays, Correlation up to 0.96,sensitivity0.2ug/ml; linearity range1.1-40 mg/L, Degree of precisionCV＜10%.

Fig.4 Comparisons of CUSAgADPN immunoassays and high-quality kits

B. Chemiluminescent Immunoassay(CLIA)

Samples（n=39） from donors containing the healthy and patients with type 2 diabetes were respectively detected using the CLIAADPN assays. CLIAADPN assays can distinguish healthy donors from patients. What’s more, the results show good correlation between CLIA ADPN assays and comparison kits. Correlation up to 0.92,Blank check out limit 50ng/ml; linearity range0.9-40 mg/L,Degree of precisionCV＜10%，recovery：average105.56%.

Fig.5 The comparisons between CLIA ADPN  and high-quality kits

C. Lateral flow immunoassay (LFIA)

39 samples from apparently healthy donors and patients with  type 2 diabetes were detected with the CUSAg LFIAADPN assay. As shown in Fig.6, the detection signals of T line were proportional to the concentration of theADPN in the sample tested by commercial kit. Correlation up to0.92,Blank check out limit 0.017ug/ml; linearity range1.5-40 mg/L,Degree of precisionCV＜15%.

Fig.6 Quantitative detection of the concentration of theADPN in the blood samples and high-quality kits

ADPN protein

A certain amount of excellent ADPN protein (Catalog Number CSBDP120B) is also offered, it could be used as calibrator in immunoassay