Validation of the IDS Octeia ELISA for the determination of insulin-like growth factor 1 in equine serum and tendon tissue extracts.

The research aims to validate the use of the IDS Octeia ELISA kit, initially developed for humans, to measure Insulin-like growth factor 1 (IGF-1), a critical tissue repair agent, in horses’ blood serum and tendon tissue. The study establishes the accuracy and reliability of the kit after a specific pretreatment procedure using glycyl-glycine.

Methods

• The research involves comparing the glycyl-glycine pretreatment protocol to the manufacturer’s recommended pretreatment procedure to see which one resulted in an accurate measurement of IGF-1 in equine serum and tendon tissue extracts.
• Intra-assay and inter-assay imprecision were evaluated through repeated measurements performed on equine serum pools. Intra-assay refers to the variability of outcomes within one test series, while inter-assay involves variability between different series.
• The researchers checked the inaccuracy of the assay by determining the linearity of diluted equine serum samples and tendon tissue extracts.
• The recovery of IGF-1, or the ability to measure it from serum and tissue extracts spiked with known amounts of IGF-1, was also evaluated. This determines the assay’s performance and efficiency.

Results

• The results showed that the IGF-1 released using the manufacturer’s pretreatment procedure was between 23% and 56% of the amount released using the glycyl-glycine pretreatment.
• The intra- and inter-assay imprecision ranged from 3.1% to 4.0%, and 7.3% to 13.9% respectively, which indicates high precision of the ELISA kit.
• The recovery rates from diluted serum samples were above 70% whether diluted with serum or PBS and reached 108% in tendon tissue extracts, demonstrating the accuracy and reliability of the ELISA kit in measurement of IGF-1.

Conclusions

• The study’s findings support the use of the IDS Octeia ELISA kit for measuring IGF-1 in equine serum and tendon tissue extracts when pretreated with glycyl-glycine. This makes it a useful and reliable tool for research in equine medicine and biochemistry.