Avaliação histológica e imunoistoquímica de dois protocolos de terapia celular no reparo do ligamento suspensório equino

Abstract

This study aimed to histologically evaluate the quality of the repair tissue in experimentally injured equine suspensory ligament samples treated with two different protocols of cell therapy. The four members of six animals were operated simultaneously to remove a fragment with punch biopsy. Two days later, each ligament received local application of a mononuclear cell fraction of bone marrow (BM), cultured mononuclear cells cultivated from adipose tissue (TA), saline (CP) or no treatment (CN) as controls. Two months later, biopsies were performed for histological analysis of the ligaments (HE, Masson trichrome and pricosirius red) and immunohistochemistry (collagen type III). Collagen fiber alignment, presence of inflammatory cells and presence of vessels (HE and Masson thichrome), birefringence intensity and tissue organization (pricosirius) and type III deposition (immunohistochemistry) were analysed. Data were compared using the Kruskal-Wallis test. Although no statistical significance (P = 0.08) was observed for fiber alignment, there was better alignment in the treated groups. Even though for the birefringence intensity (verified by pricosirius staining), there was no difference between the treated groups (MO and TA) the values were higher than control groups, indicating better deposition of collagen fiber in ligaments subjected to cell therapy. The presence of inflammatory cells and intense staining for collagen type III demonstrate the healing process in all groups. In conclusion, the results demonstrate a potential for the treatment of equine suspensory ligament injuries, producing better tissue organization during the study period.