1. Investigación

PRGF®-Endoret® se caracteriza por una concentración moderada de PLT y la ausencia de glóbulos rojos y leucocitos. El objetivo de este trabajo es estandarizar un protocolo de obtención de PRP para el gato y estudiar cómo la presencia de enfermedades virales como la leucemia (FeLV) y la inmunodeficiencia felina (VIF) podrían influir en su calidad y composición. Se incluyeron en el estudio 30 gatos sanos y se recogieron 3 tubos de 9 ml de sangre y se centrifugaron siguiendo diferentes protocolos: 255 g, 260 gy 265 g durante 10 minutos. Los resultados demostraron que el proceso de centrifugación a 265 g durante 10 minutos logró una concentración óptima de PLT, sin presencia de leucocitos. Respecto al VPM, fue significativamente mayor en la sangre basal que en las fracciones PRP y PPP. Las concentraciones de PDGF-BB y TGF-ß1 fueron estadísticamente mayores en la fracción PRP que en la fracción PPP. Posteriormente, se aplicó el protocolo estandarizado a 11 gatos positivos para FeLV y 16 gatos positivos para FIV. La concentración de PLT en gatos FeLV no alcanzó el mínimo requerido por la tecnología PRGF®-Endoret®, sin embargo, los valores se acercaron a los de gatos sanos. Por otro lado, el protocolo estandarizado no fue reproducible en gatos FIV.

Platelet functionality plays a crucial role in marine mammals. Alterations in platelet function can result from stress, pathologies, or exposure to xenobiotics, among others. The early detection of platelet function abnormalities is essential in these species to prevent advanced pathology and mitigate potential risks. Our main objective was to establish a range of physiological values of platelet function in bottlenose dolphins (Tursiops truncatus), beluga whales (Delphinapterus leucas), sea lions (Otaria flavescens) and walruses (Odobenus rosmarus). Intraplatelet Ca2+ mobilization using adenosine diphosphate (ADP) as a platelet agonist was used as a platelet function biomarker, adapting the methodology previously described by us in dolphins (Felipo-Benavent et al., 2022) to the rest of the species. The assay was also adapted to a seal (Phoca vitulina). Numerical indicators of intraplatelet Ca2+ mobilization kinetics were established, and statistical analyses were performed to compare the effects of species, sex, age, aquarium and species. Significant differences were observed between species, being the platelets of the sea lions the more reactive to the agonist. This work demonstrates the usefulness of this assay in the diagnosis or monitoring of animals with hemostatic diseases, showing two clinical cases in which intraplatelet calcium mobilization values were altered in marine mammals suffering haemorrhages. This assay may also serve as a means to monitor environmental changes and their potential impact on the health of marine mammal populations.

Autologous platelet-rich plasma (PRP) contains growth factors (GFs) that modulate the expression of inflammatory cells; thus, these products could be considered a good strategy to favor tissue regeneration in feline immunodeficiency (FIV) positive cats. However, there is no scientific documentation on obtaining PRP in FIV-positive cats. Authors hypothesized that PRP can be obtained in FIV cats following the PRGF®-Endoret® methodology. The objectives of this study were to compare the platelet, erythrocyte, and leukocyte concentration between whole blood (WB) and the PRP; and determine the concentration of platelet-derived growth factor BB (PDGF-BB) and transforming growth factor β1 (TGF-β1) in FIV-positive cats. Sixteen adults FIV-positive asymptomatic cats were included in the study. WB samples were drawn and the PRP was obtained by centrifugation at 265g for 10 min. Erythrocyte and leukocyte, platelets, and mean platelet volume (MPV) were determined both in WB and in PRP. PDGF-BB and TGF-β1 concentrations were additionally determined in PRP. Platelet concentration increased 1.1 times in PRP fraction compared to WB, but no significant differences were reported. MPV was statistically higher in WB than in PRP (p = 0.001). Erythrocytes and leukocytes counts were decreased by 99% and 92%, respectively in the PRP fraction (p < 0.001). Regarding TGF-ß1, a higher concentration was shown in the PRP (p < 0.02). Although the product obtained could not be classified as PRP according to the PRGF®-Endoret® methodology, based on the drastic reduction of RBC and WBC, the PLT concentrate is of high purity.