An immuno polymerase chain reaction screen for the detection of CJC-1295 and other growth-hormone-releasing hormone analogs in equine plasma.

This research introduces a novel method for detecting CJC-1295, a performance-enhancing drug, in horse plasma via immuno-polymerase chain reaction (I-PCR).

Background of the Research

• CJC-1295 is a peptide-based drug that triggers the release of growth hormone (GH) from the pituitary gland.
• What sets CJC-1295 apart from similar performance-enhancing peptides is its reactive maleimidopropionic acid group. This group allows the peptide to chemically bond to free thiols on the surface of plasma proteins.
• Upon bonding with plasma proteins, CJC-1295 remains in the bloodstream much longer than its non-conjugated counterparts, which are quickly expelled from the body.
• Traditional top-down mass-spectrometry-based peptide screening protocols have been unsuccessful in detecting CJC-1295 because, once it bonds with plasma proteins, the peptide becomes a large protein with an indeterminate molecular weight.

Purpose and methods of the Research

• This study aimed to create a method to detect CJC-1295 in horse plasma due to its potential misuse in horse racing.
• The researchers developed an immuno-polymerase chain reaction (I-PCR) assay using a set of monoclonal antibodies raised against the CJC-1295 peptide.
• The I-PCR assay was capable of detecting CJC-1295-protein conjugate at levels as low as 0.8 pg/mL in horse plasma.

Outcomes and Future Application

• However, the occurrence of naturally occurring equine GHRH required a detection threshold for CJC-1295 in horse plasma to be set at 50 pg/mL.
• The utility of the I-PCR assay in monitoring the unauthorized use of CJC-1295 was validated using equine blood samples from race horses in which it had been administered.
• Future use of this assay could prove critical in preventing the illegal use of performance-enhancing drugs like CJC-1295 in professional horse racing.