Adiponectin is an adipokine exclusively expressed in adipose tissues with potent anti-diabetic, anti-atherogenic and anti-inflammatory functions.
In humans, decreased serum adiponectin levels are associated with increased body mass index (BMI), decreased insulin sensitivity, less favourable plasma lipid profiles, increased inflammation and increased risk for the development of type 2 diabetes, hypertension and coronary heart diseases

This assay is a quantitative sandwich ELISA using monoclonal antibodies against human adiponectin. The immunoplate is pre-coated with a monoclonal antibody specific for human adiponectin. Standards and samples are pipetted into the wells and any human adiponectin present is bound by the immobilized antibody. After washing away any unbound substances, a horseradish peroxidase (HRP)-linked monoclonal antibody specific for human adiponectin is added to the wells. After a final wash step, an HRP substrate solution is added and colour develops in proportion to the amount of human adiponectin bound initially.  The assay is stopped and the optical density of the wells determined using a microplate reader. Since the increases in absorbance are directly proportional to the amount of captured human adiponectin, the unknown sample concentration can be interpolated from a reference curve included in each assay.

A. Typical representation of standard curve

The following standard curve is provided for demonstration only. A standard curve should be generated for each set of sample assay. 

Adiponectin (ng/mL)	Absorbance (450 nm)	Blanked Absorbance
0	0.068	0
1.56	0.112	0.044
3.12	0.156	0.088
6.25	0.248	0.18
12.5	0.418	0.35
25	0.724	0.656
50	1.384	1.316
100	2.469	2.401

 

B. Sensitivity

The lowest level of human adiponectin that can be detected by this assay is 1.56 ng/mL.

 

C. Specificity

The antibody pair used in this assay is specific to human adiponectin and does not cross-react with mouse and rat adiponectin, and other cytokine or hormone molecules including human resistin, TNFa, ANGPTL4, insulin, leptin and IL6.

 

D. Precision

The assay variations of this ELISA kits were studied on four human serum samples with varying concentrations of endogenous adiponectin. The mean within variation was calculated from results of five duplicate determinations in each assay of the indicated samples. The mean between variations of each sample was calculated from results of four separate assays with duplicate samples in each assay.

 

E. Recovery

Varying amounts of human adiponectin were added to three human serum samples and the Adiponectin content was determined in three separate assays. The % of recovery = observed adiponectin concentrations/expected adiponectin concentrations x 100%.

	Average recovery	Range (%)
1	99.3	97-104
2	99.8	98-103
3	101.1	99-105
4	100.2	98-104

1. Li H, Dong K, Fang Q, Hou X, Zhou M, Bao Y, Xiang K, Xu A, Jia W. High serum level of fibroblast growth factor 21 is an independent predictor of non-alcoholic fatty liver disease: a 3-year prospective study in China. Journal of hepatology. 2013 Mar 1;58(3):557-63.
2. Li X, Tse HF, Yiu KH, Zhang C, Jin LJ. Periodontal therapy decreases serum levels of adipocyte fatty acid‐binding protein in systemically healthy subjects: a pilot clinical trial. Journal of periodontal research. 2013 Jun;48(3):308-14.
3. Heilbronn LK, Campbell LV, Xu A, Samocha-Bonet D. Metabolically protective cytokines adiponectin and fibroblast growth factor-21 are increased by acute overfeeding in healthy humans. PloS one. 2013 Oct 18;8(10):e78864.
4. Wu G, Li H, Fang Q, Jiang S, Zhang L, Zhang J, Hou X, Lu J, Bao Y, Xu A, Jia W. Elevated circulating lipocalin-2 levels independently predict incident cardiovascular events in men in a population-based cohort. Arteriosclerosis, thrombosis, and vascular biology. 2014 Nov;34(11):2457-64.
5. Chen DL, Liess C, Poljak A, Xu A, Zhang J, Thoma C, Trenell M, Milner B, Jenkins AB, Chisholm DJ, Samocha-Bonet D. Phenotypic characterization of insulin-resistant and insulin-sensitive obesity. The Journal of Clinical Endocrinology & Metabolism. 2015 Nov 1;100(11):4082-91.
6. Elie AG, Jensen PS, Nissen KD, Geraets IM, Xu A, Song E, Hansen ML, Irmukhamedov A, Rasmussen LM, Wang Y, De Mey JG. Adipokine imbalance in the pericardial cavity of cardiac and vascular disease patients. PloS one. 2016 May 3;11(5):e0154693.
7. Chen DL, Brown R, Liess C, Poljak A, Xu A, Zhang J, Trenell M, Jenkins A, Chisholm D, Samocha-Bonet D, Macefield VG. Muscle sympathetic nerve activity is associated with liver insulin sensitivity in obese non-diabetic men. Frontiers in physiology. 2017 Feb 28;8:101.
8. Chan JS, Li A, Ng SM, Ho RT, Xu A, Yao TJ, Wang XM, So KF, Chan CL. Adiponectin potentially contributes to the antidepressive effects of Baduanjin Qigong exercise in women with chronic fatigue syndrome-like illness. Cell transplantation. 2017 Mar;26(3):493-501.
9. Yang K, Deng HB, Man AW, Song E, Zhang J, Luo C, Cheung BM, Yuen KY, Jensen PS, Irmukhamedov A, Elie AG. Measuring non‐polyaminated lipocalin‐2 for cardiometabolic risk assessment. ESC heart failure. 2017 Nov;4(4):563-75.
10. Li H, Wu G, Fang Q, Zhang M, Hui X, Sheng B, Wu L, Bao Y, Li P, Xu A, Jia W. Fibroblast growth factor 21 increases insulin sensitivity through specific expansion of subcutaneous fat. Nature communications. 2018 Jan 18;9(1):1-6.
11. Wong YK, Cheung CY, Tang CS, Au KW, Hai JS, Lee CH, Lau KK, Cheung BM, Sham PC, Xu A, Lam KS. Age-biomarkers-clinical risk factors for prediction of cardiovascular events in patients with coronary artery disease. Arteriosclerosis, thrombosis, and vascular biology. 2018 Oct;38(10):2519-27.
12. Elie AG, Bloksgaard M, Sun WY, Yang K, Man AW, Xu A, Irmukhamedov A, Riber LP, Wang Y, De Mey JG. Local enrichment of fatty acid-binding protein 4 in the pericardial cavity of cardiovascular disease patients. PloS one. 2018 Nov 5;13(11):e0206802.
13. Xiao Y, Xiao X, Xu A, Chen X, Tang W, Zhou Z. Circulating adipocyte fatty acid-binding protein levels predict the development of subclinical atherosclerosis in type 2 diabetes. Journal of Diabetes and its Complications. 2018 Dec 1;32(12):1100-4.
14. Tang A, Coster AC, Tonks KT, Heilbronn LK, Pocock N, Purtell L, Govendir M, Blythe J, Zhang J, Xu A, Chisholm DJ. Longitudinal changes in insulin resistance in normal weight, overweight and obese individuals. Journal of clinical medicine. 2019 May;8(5):623.
15. Mak LY, Lee CH, Cheung KS, Wong DK, Liu F, Hui RW, Fung J, Xu A, Lam KS, Yuen MF, Seto WK. Association of adipokines with hepatic steatosis and fibrosis in chronic hepatitis B patients on long‐term nucleoside analogue. Liver International. 2019 Jul;39(7):1217-25.
16. Harari A, Coster AC, Jenkins A, Xu A, Greenfield JR, Harats D, Shaish A, Samocha-Bonet D. Obesity and insulin resistance are inversely associated with serum and adipose tissue carotenoid concentrations in adults. The Journal of nutrition. 2020 Jan 1;150(1):38-46.
17. Liu Y, Wang Y, Ni Y, Cheung CK, Lam KS, Wang Y, Xia Z, Ye D, Guo J, Tse MA, Panagiotou G. Gut microbiome fermentation determines the efficacy of exercise for diabetes prevention. Cell metabolism. 2020 Jan 7;31(1):77-91.
18. Lee CH, Lui DT, Cheung CY, Fong CH, Yuen MM, Chow WS, Woo YC, Xu A, Lam KS. Higher Circulating Adiponectin Concentrations Predict Incident Cancer in Type 2 Diabetes–The Adiponectin Paradox. The Journal of Clinical Endocrinology & Metabolism. 2020 Apr;105(4):e1387-96.
19. Lui MM, Mak JC, Chong PW, Lam DC, Ip MS. Circulating adipocyte fatty acid–binding protein is reduced by continuous positive airway pressure treatment for obstructive sleep apnea—a randomized controlled study. Sleep and Breathing. 2020 Sep;24(3):817-24.
20. Botta A, Forest A, Daneault C, Pantopoulos K, Tantiworawit A, Phrommintikul A, Chattipakorn S, Chattipakorn N, Des Rosiers C, Sweeney G. Identification of Circulating Endocan-1 and Ether Phospholipids as Biomarkers for Complications in Thalassemia Patients. Metabolites. 2021 Feb;11(2):70.
21. Bishay RH, Tonks KT, George J, Samocha-Bonet D, Meyerowitz-Katz G, Chisholm DJ, James DE, Greenfield JR. Plasma bile acids more closely align with insulin resistance, visceral and hepatic adiposity than total adiposity. The Journal of Clinical Endocrinology & Metabolism. 2021 Mar;106(3):e1131-9.