Protective effect of mesenchymal stromal cell-derived secretome against Loxosceles intermedia spider venom-induced skin necrosis in rabbits
background:
Loxoscelesism refers to a set of clinical symptoms caused by spider bites. Roxosceles genus. The typical clinical presentation is characterized by an intense inflammatory reaction at the bite site followed by local necrosis and is classified as cutaneous loxoscelism. This skin morphology is difficult to heal and proposed treatments are neither specific nor effective. The aim of this study was to evaluate the protective effect of mesenchymal stromal cell-derived secretome against tick-induced skin necrosis. Loxosceles intermedia Spider venom for rabbits.
Method:
Sixteen rabbits were divided into four groups (n = 4). Except for group 1 (G1), which received only PBS, the other three groups (G2, G3, and G4) were initially administered 10 μg of L. Intermedia Venom diluted in 100 μL NaCl 0.9% was injected intradermally in the interscapular region. Thirty minutes after challenge, all groups except group 2 were administered secretome. Group 1 (G1 control group) received 60 μg secretome in 0.15 M PBS via intradermal injection (ID). Group 2 (G2) received 0.9% NaCl via ID. Group 3 (G3) received 60 μg secretome via ID and group 4 (G4) received 60 μg secretome via intravenous route. Rabbits were evaluated daily and euthanized and necropsied after 15 days, and skin samples around the necrotic lesions were taken for histological analysis.
result:
No edema, erythema, hemorrhagic halo, or necrosis was observed in G1 rabbits. In G2, G3, and G4 animals, edema appeared after 6 hours. However, mild edema was observed in G2 and G3 animals. Hemorrhagic halos were observed after 6 hours and 3 days in G2, G3, and G4 animals. Grossly, only one of four G4 animals had lesions that progressed to necrotic skin wounds. Microscopic evaluation showed no changes in the skin of G1 animals. L. Intermedia The venoms showed similar changes such as necrosis and heterophil infiltration, but G4 animals showed fibroblast activation, early development of connective tissue, angiogenesis, and tissue re-epithelialization, indicating a more pronounced healing process.
Conclusion:
These results suggest that secretion from mesenchymal stromal cells cultured in xenogeneic and human component-free medium is Roxosceles Spiders bite and release venom.
Rodrigues, G. M., Almeida, M. E. de ., Marcelino, S. A. C., Fernandes, P. B. U., Cruz, J. O. P. da ., Araújo, F. L., Ferreira, R. da S., Botelho, A. F. M., Bedoya, F. J., Cahuana, G. M., Hitos, A. B., Soria, B., Costal-Oliveira, F., Duarte, C. G., Tejedo, J. R., Chávez-Olórtegui, C., & Melo, M. M.. (2024). Protective effects of mesenchymal stromal cell-derived secretome on dermonecrosis induced in rabbits by Loxosceles intermedia spider venom. Journal of Venomous Animals and Toxins Including Tropical Diseases, 30, e20240004. https://doi.org/10.1590/1678-9199-JVATITD-2024-0004
