Objectives: The aim of this study was to isolate feline dental pulp stem cells (fDPSCs) and characterize their clonogenic and proliferative abilities, as well as their multipotency, immunophenotype and cytogenetic stability. Methods: Dental pulp was isolated by explant culture from two cats <1 year old at post mortem. Their clonogenicity was characterized using a colony-forming unit fibroblast assay, and their proliferative ability was quantified with a doubling time assay in passages 2, 4 and 6 (P₂, P₄ and P₆, respectively). Multipotency was characterized with an in vitro trilineage differentiation assay in P₂, and cells were immunophenotyped in P₄ by flow cytometry. Chromosomic stability was evaluated by cytogenetic analysis in P₂, P₄ and P₆. Results: The fDPSCs displayed spindle and epithelial-like morphologies. Isolated cells showed a marked clonogenic capacity and doubling time was maintained from P₂ to P₆. Trilineage differentiation was obtained in one sample, while the other showed osteogenic and chondrogenic differentiation. Immunophenotypic analysis showed fDPSCs were CD45⁻, CD90⁺ and CD44⁺. Structural and numerical cytogenetic aberrations were observed in P₂–P₄. Conclusions and relevance: In this study, fDPSCs from two cats were isolated by explant culture and immunophenotyped. Cells displayed clonogenic and proliferative ability, and multipotency in vitro, and signs of chromosomic instability were observed. Although a larger study is needed to confirm these results, this is the first report of fDPSC isolation and in vitro characterization.

Stem cell therapy in cat patients needs a high quantity of mesenchymal stromal/stem cells (MSCs) requiring in vitro propagation under culture conditions which may potentially impact cellular characteristics and genetic stability. This study aimed to assess the in vitro characteristics and cytogenetic stability of cat adipose tissue-derived MSCs (cAT-MSCs). For this purpose, morphological features, clonogenic potential, and proliferative capacity of cAT-MSCs were assessed at passages 2 (P₂), P₄, and P₆. Multipotency and immunophenotype were evaluated. Cytogenetic analyses were conducted up to P₆. The cAT-MSCs exhibited a spindle-shaped morphology in early passages. The doubling time increased from 2.5 days at P₂ to 9.4 at P₄ and 10.5 at P₆, accompanied by the observation of nuclear abnormalities such as cluster formation, karyorrhexis, karyolysis, and a decline in the mitotic index at P₄. Cells demonstrated multipotency capacity and were CD45−, CD90+, and CD44+. Metaphase analysis at P₂ and P₄ revealed some indications of structural instability such as gaps, breaks, deletions, duplications, and early chromatid segregation, but these alterations did not show an increase across passages. In conclusion, cAT-MSCs decreased their proliferative capacity after P₄, accompanied by morphological alterations and signs of structural instability.

Traumatic injuries in turtles pose a significant challenge for veterinarians, requiring extended follow-up and rehabilitation periods. With conventional healing methods often yielding limited results, the realm of regenerative medicine in reptiles and amphibians has offered promising alternatives. Among these, the utilization of thrombocyte-leukocyte rich plasma and analogous hemocomponents akin to platelet-rich plasma in mammals has garnered attention. Hence, the objective of this study was to explore therapeutic hemocomponents in reptiles, specifically thrombocyte-leukocyte rich plasma, and its application in a clinical case involving Chelonia mydas. Autologous thrombocyte-leukocyte rich plasma was prepared via a density gradient centrifugation process to isolate the buffy coat and concentrate thrombocytes and leukocytes in the final formulation. The selected clinical case involved a green turtle (Chelonia mydas) undergoing rehabilitation at the Karumbé center, exhibiting lesions and abscesses in the jaw and flipper regions. Treatment entailed abscess removal, antibiotic administration, and the application of gelified thrombocyte-leukocyte rich plasma in the affected areas. Results demonstrated a recovery rate of 20.8% for thrombocytes and leukocytesin the thrombocyte- leukocyte rich plasma preparation, which effectively gelled upon application. Regarding the clinical case evolution, after 2 months of follow-up, an improvement in wound healing was observed. In conclusion, this is the first report of the preparation of thrombocyte-leukocyte rich plasma in Chelonia mydas and its application in a clinical case with favorable progression. However, more cases are needed in this species and type of lesion to obtain conclusive results on its beneficial effects in turtles.

La fibrina rica en plaquetas y leucocitos (L-PRF) es un producto sanguíneo de segunda generación que puede utilizarse como relleno biológico. Esto se debe a que la densa red de fibrina que se forma actúa como un andamio celular y proporciona factores de crecimiento de manera sostenida, lo que promueve la curación. En este estudio se evaluaron dos casos clínicos de pacientes que presentaron fístula oronasal (FON) atendidos en el Servicio de Odontoestomatología de la Facultad de Veterinaria, Udelar. Se extrajo el diente afectado, se cerró la FON mediante un colgajo mucoperióstico y se colocó L-PRF en la cavidad dental para promover la cicatrización. En los controles posoperatorios de los días 7, 14 y 30 se observaron resultados favorables, sin complicaciones ni recurrencias para ambos casos clínicos. El uso de L-PRF en la resolución quirúrgica de la FON resultó ser una técnica rápida, económica y sencilla, fácil de realizar en una clínica veterinaria, inofensiva y de bajo riesgo, resultó un novedoso tratamiento para el cierre de defectos alveolares.

Adipose tissue can be a source of bovine mesenchymal stromal/stem cells (MSCs). However, most studies do not incorporate post-mortem collection or in vitro differentiation of these cells from bovine fat and other sources into three mesodermal lineages. This study characterized and cryopreserved bovine adipose tissue-derived MSCs (AD-MSCs) collected post-mortem. Cells were isolated from cattle (Bos taurus) and cultured under standard conditions for ex vivo expansion and cryopreservation. Cell growth kinetics was determined by cell doubling time after consecutive cellular passages. Clonogenic capacity was determined using the colony-forming unit fibroblast (CFU-F) assay. The trilineage differentiation assay was performed to determine its in vitro multipotency. The in vitro proliferation and clonogenic capacity of bovine AD-MSCs was maintained across successive passages (P₂-P₆). Greater clonogenic capacity was found in fresh than post-cryopreservation cells. Cells showed multipotential capacity in adipose, cartilage and bone lineages. In conclusion, no changes were observed in the growth kinetics and colony-forming capacity of the successive passages evaluated. Clonogenic capacity was higher in fresh than post-cryopreserved cells.