Procalcitonin Detection in Veterinary Species: Investigation of Commercial ELISA Kits

Abstract

In human medicine, procalcitonin (PCT), the precursor of calcitonin, is used for the rapid identification of the origin and severity of sepsis. In veterinary medicine, PCT has been studied in horses, cattle, and dogs, but the use of PCT in diagnostic and/or prognostic settings is not possible because of the lack of validated assays to obtain reference ranges. The aim of the present study was the investigation of commercially available ELISA kits for the detection of canine and equine PCT in plasma samples. Validation of the ELISA kits was performed by using species-specific recombinant proteins spiked both in plasma and buffer samples; linearity, limit of detection (LOD), recovery, and intra-assay and inter-assay variability were calculated. Moreover, clinical samples obtained from sick and healthy animals were also analyzed with the tested kits. Canine PCT was measured with a recombinant canine and a canine PCT ELISA kit. Equine PCT was measured with an equine and a human ELISA PCT kit. Our data demonstrate that the canine recombinant PCT ELISA kit can be used to measure canine PCT in plasma samples, showing an intra-assay and inter-assay coefficient of variation less than 20% and a LOD of 11 pg/mL, whereas the present results do not support the use of the canine PCT ELISA kit. The human PCT ELISA kit is suitable to detect equine PCT with a LOD of 56 ng/mL, whereas the equine PCT ELISA kit did not detect recombinant equine PCT.

Improving clinical outcomes via responsible antimicrobial use in horses

“…PCT has also similarly been used in conjunction with other clinicopathologic results as an indicator of intestinal ischaemia to identify horses with a strangulating lesion, necessitating surgery (Kilcoyne et al 2020). Recently, a human PCT ELISA kit was found to be suitable to detect equine PCT with a limit of detection of 56 ng/mL (Battaglia et al 2020). In foals, however, PCT was not a useful biomarker in pneumonia associated with Rhodococcus equi (Barton et al 2016) and there was no significant difference in leukocyte PCT mRNA levels identified between septic and nonseptic foals (Pusterla et al 2006).…”

“…Recently, a human PCT ELISA kit was found to be suitable to detect equine PCT with a limit of detection of 56 ng/mL (Battaglia et al . 2020). In foals, however, PCT was not a useful biomarker in pneumonia associated with Rhodococcus equi (Barton et al .…”

Detection of canine and equine procalcitonin for sepsis diagnosis in veterinary clinic by the development of novel MIP-based SPR biosensors

“…This is of particular interest for ePCT, due to the current lack of specific anti-equine antibodies. In fact, available ELISA kits for ePCT (for research purposes only) are based on human anti-PCT antibodies [17,20] thanks to the homology between equine and human PCTs [39]. Nevertheless, the limit of detection obtained in these studies is higher than that reported by manufacturer's instructions of equine PCT kit and this could be related to the use of non-species specific i.e.…”

“…Conversely, in veterinary patients, only three commercial ELISA kits are available for dogs or horses, not fully validated, and suitable only for research purposes. In particular, only one ELISA-type immunoassay is reported in literature for equine PCT, based on human antibodies since there is no availability of specific antibodies [17][18][19][20][21].…”

Programmable Hybridization Assemble Nicked Displacement Amplification for Detecting Ricin Toxin

“…Currently, enzyme-linked immunosorbent assay is the most widely used method for the detection of ricin [9][10][11]. Corresponding commercial detection kits have also been developed, but the sensitivity and detection range are limited [12][13][14]. In order to improve the detection sensitivity, our laboratory also tried to amplify the detection signal with isothermal ampli cation, and the detection sensitivity was improved to a certain extent [15].…”