Investigating the use of mesenchymal stem cells (MSCs) as a treatment alternative for chronic inflammation is expanding. Cats are commonly afflicted with inflammatory conditions and the study of MSCs for their therapeutic benefits is ongoing.
Along with regenerative capabilities, MSCs affect the immunomodulating properties of many types of immune cells. In vitro studies propose that MSCs should be in the proximity of the target cells and in large enough numbers to induce the required therapeutic effect. In vivo studies also propose there are paracrine (a substance secreted by a cell and having an effect on surrounding cells) effects of MSCs on other cells, another important factor.
Because of concerns that MSCs given intravenously may be retained in large numbers in the pulmonary vasculature, other methods are being evaluated to deliver MSCs to such areas as abdominal organs. One method of delivery is by intraperitoneal administration (IP) of MSCs. This study’s goal was to look at the safety of intraperitoneal injection of autologous (use of the patient’s own stem cells) MSCs in cats.
Ten healthy adult cats had subcutaneous fat tissue collected at the time of their ovariohysterectomy. The fat tissue was prepared and underwent differentiation to MSCs displaying the expected appropriated surface markers. Three weeks later post surgery and following baseline laboratory analysis, five of the cats received MSCs intraperitoneally with ultrasound guidance. The other five cats were injected as controls with sterile phosphate buffered saline. All of the cats were monitored for six weeks with daily physical examinations and weekly clinicopathological evaluations. Ultrasound examination of the abdomen was repeated at weeks one and five after injection.
The results indicated that IP administration of autologous MSCs appears to be safe and feasible with ultrasound technology as a treatment in cats. No severe adverse reactions were noted; two MSC treated can were mildly lethargic and less interactive immediately after injection. In the future, more than one injection of MSCs for frequency and a higher dose of MSCs per administration should be evaluated for safety. (VLT)