IGFBP-3 Mouse/ Rat ELISA

Research topic

Animal studies, Growth hormone and factor-related products

Features

• Quantitative determination of mouse/rat IGFBP-3 without sample pretreatment
• Inter-Assay variation of 8.4% and Intra-Assay variation of 4.6%
• Analytical sensitivity of 0.018 ng/ml (18 pg/ml; 1,8 pg/well)

Storage/Shipping

The microtiter plate wells and all undiluted reagents are stable until the expiry date if stored in the dark at 2–8°C. Store the unused seal strips and microtiter wells together with the desiccant at 2° to 8°C. The Substrate Solution (S), stabilised H2O2-Tetramethylben­cidine, is photosensitive – store and incubate in the dark. Reconstituted Components (Standards A – G and Control Sera) should be stored at –20°C (or below). Freezing extends the expiry at least 2 months. Avoid repeated freeze-thaw cycles. In case you plan to perform multiple independent determinations over a longer period with one kit, you should aliquot the components prior to freezing into suitable smaller volumes. This is strongly recommended.

Summary

Growth Hormone, Insulin-like Growth Factors and their binding proteins build up an endocrine system regulating not only longitudinal growth in humans but also influencing a broad variety of other physiological and pathophysiological processes like energy metabolism or tumor growth. Most effects of Growth Hormone (GH) are exerted by Insulin-like Growth Factors (IGF) mainly produced by the liver but also locally by specific tissues. The effects of IGF are also regulated. Specific binding proteins (IGFBP 1–7) regulate bioavailability of IGF. After proteolytic cleavage of the binding proteins IGF is set free and able to bind to its receptor. The autophosphorylation of this thyrosine kinase receptor activates intra cellular signalling cascades. Some of these IGFBPs not only regulate the availability of IGF but also exert IGF-independent effects on cell physiology. IGFBP-3 is the most abundant IGFBP in circulation and therefore of special relevance in regulation of IGF effects. This is reflected by the indicative value of serum IGFBP-3 concentration in diagnostics of growth disturbances. IGFBP-3 has also been shown to be able to induce apoptosis, promote tumor growth and inhibit cellular migration and metastasis dependent on tissue and tumor stage.

Assay format

Sandwich ELISA, Biotin-labelled antibody

Calibration Curve

Calibration range

0.078 to 5 ng/ml

Limit of detection

0.018 ng/ml

References to summary

• Silha JV, Murphy LJ: Insulin-like growth factor binding proteins in development.Adv Exp Med Biol. 2005;567:55–89
• Yakar S, Sun H, Zhao H, Pennisi P, Toyoshima Y, Setser J, Stannard B, Scavo L, Leroith D: Metabolic effects of IGF-I deficiency: lessons from mouse models.Pediatr Endocrinol Rev. 2005 Sep;3(1):11–19
• Silha JV, Murphy LJ: Insights from insulin-like growth factor binding protein transgenic mice.Endocrino­logy. 2002 Oct;143(10):37­11–4.
• Firth SM, Baxter RC: Cellular actions of the insulin-like growth factor binding proteins.Endocr Rev. 2002 Dec;23(6):824–854
• Schneider MR, Lahm H, Wu M, Hoeflich A, Wolf E: Transgenic mouse models for studying the functions of insulin-like growth factor-binding proteins.FASEB J. 2000 Apr;14(5):629–40