Retinol Binding Protein 4 (RBP4) ELISA Kit

  • Created on the 28 March, 2017.


Retinol binding protein 4 (RBP4) is a member of the lipocalin family and is a 21kDa secreted protein which has important roles in transporting retinol (vitamin A) to tissues. It has the ability to deliver retinol from the liver stores to the peripheral tissues and in plasma, the RBP-retinol complex can interact with transthyretin resulting in preventing its loss via kidney glomeruli. Any deficiency of vitamin A can lead to blocking the secretion of the binding protein post-translationally and this can cause a defective delivery and supply to the epidermal cells.

Elevated levels of serum RBP4 have been correlated with type 2 diabetes and insulin resistance in several clinical studies. It has also been recently been described as an adipokine that can contribute to insulin resistance in the AG4KO mouse model, it is secreted by adipocytes and has a vital role in providing a signal to other cells under conditions where there is reduced levels of plasma glucose. Clinical studies have recently found a correlation between elevated serum RBP4 level and subclinical inflammation, whereas other studies have revealed that RBP4 has the ability to induce inflammation in macrophages. The standard used in this ELISA assay is recombinant protein, with E19-L201 amino acid sequence with a molecular weight of 22 kDa.


Human RBP-4 ELISA kit is designed for measuring in vitro quantitative levels of retinol binding protein 4 (RBP4) in human serum, urine, plasma and cell culture supernatants. This assay has a minimum detection limit of < 10.0 pg/ml.


The minimum detection sensitivity level of retinol binding protein 4 using this human RBP-4 ELISA kit was 10.0 pg/ml. The dynamic assay range for this kit is 312.0 – 20,000 pg/ml.


  1. Is retinol binding protein 4 a link between adiposity and cancer? Horm Mol Biol Clin Investig. (2015) 23 (2): 39-46. Review. Noy N., et al.
  2. Serum retinol-binding protein: a link between obesity, insulin resistance, and type 2 diabetes. Nutr Rev. (2007) 65 (5): 251-6. Review. Wolf G.
  3. Vitamin A and Diabesity: New Insight for Drug Discovery. Mini Rev Med Chem. (2016) 16 (9): 738-42. Review. Cione E., et al.
  4. RBP4: a controversial adipokine. Eur J Endocrinol. (2011) 165 (5): 703-11. Review. Kotnik P., et al.
  5. Retinol-binding protein-4 in experimental and clinical metabolic disease. Expert Rev Mol Diagn. (2008) 8 (3): 289-99. Review. von Eynatten M. and Humpert P.M.


  • Full Name: Retinol Binding Protein 4 (RBP4) ELISA Kit
  • Reactivity: Human
  • Sample Type: Cell Culture Supernatant, Serum, Plasma, Urine
  • Sensitivity: < 10.0 pg/ml



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