Complications associated with bone marrow sampling in dogs and cats

Isolation and Characterization of Canine Adipose-Derived Mesenchymal Stromal Cells: Considerations in Translation from Laboratory to Clinic

In allogeneic MSC implantation, the cells are isolated from a donor different from the recipient. When tested, allogeneic MSCs have several advantages over autologous ones: faster cell growth, sufficient cell concentration, and readily available cells for clinics. To ensure the safe and efficient use of allogeneic MSCs in clinics, the MSCs need to be first tested in vitro. With this study, we paved the way by addressing the in vitro aspects of canine adipose-derived MSCs, considering the limited studies on the clinical use of canine cells. We isolated cAD-MSCs from canine falciform ligament fat and evaluated their viability and proliferation using an MTS assay. Then, we characterized the MSC-specific antigens using immunophenotyping and immunofluorescence and demonstrated their potential for in vitro differentiation. Moreover, we established shipping and cryobanking procedures to lead the study to become an off-the-shelf therapy. During expansion, the cells demonstrated a linear increase in cell numbers, confirming their proliferation quantitatively. The cells showed viability before and after cryopreservation, demonstrating that cell viability can be preserved. From a clinical perspective, the established shipping conditions demonstrated that the cells retain their viability for up to 48 h. This study lays the groundwork for the potential use of allogeneic cAD-MSCs in clinical applications.

Feline Leishmaniasis Caused by Leishmania infantum: Parasite Sequencing, Seropositivity, and Clinical Characterization in an Endemic Area From Brazil

Zoonotic leishmaniasis caused by Leishmania infantum is a disease of One Health concern since human and animal cases and environmental damage are interconnected. L. infantum has a complex epidemiological cycle with multiple hosts, including mammals-humans, domestic, and wild animals-and arthropod vectors. Knowledge on mammal infections in endemic areas is crucial for developing control strategies. This work aimed to detect and characterize L. infantum infection in domestic cats from areas where human and canine leishmaniasis cases occur. No cases of feline leishmaniasis (FeL) had been previously reported in those areas. Five municipalities from Bahia state were chosen, comprising 2,480.8 km² with 1,103,866 inhabitants. Ninety domiciliated and/or sheltered cats underwent clinical examination and serology by a rapid reference test recommended by the Brazilian government. Cytology, PCR, and parasite DNA sequencing were performed in bone marrow samples. Rapid tests detected antibodies in 5.6% (5/90) of the cats. Leishmania infantum infection was confirmed in 7.8% (7/90) of the cats by PCR, sequencing, and parasite isolation. Three out of the five municipalities (60%) had infected cats, and PCR positivity varied from 6.9 to 29%. One cat was categorized as harboring active L. infantum infection with amastigote forms in bone marrow smears. No clinical signs were detected at the first clinical exam, but 1 month later the cat developed severe FeL. The cat isolate was grown in culture, typed and its DNA sequence was homologous to the L. infantum reference strain (PP75). In conclusion, cats are potential hosts and may acquire L. infantum in endemic areas where canine and human cases occur. For cats, the need for surveillance, differential diagnosis and clinical care is highly recommended since a fast clinical progression of FeL developed in a subclinical animal. An accurate standardized immunodiagnostic assay for FeL is warranted.