Palmitoleic Acid Extracted from Fish Oil Inhibit aGVHD By Immune Regulation

Objective: This study aims to explore the immunosuppressive effect of palmitoleic acid (POA), derived from fish oil extract, on lymphocytes in vitro and its potential impact on the clinical outcome and survival prognosis of rodents with acute graft-versus-host disease (aGVHD).

Methods: In vitro experiments involved using CCK8 to determine the influence of various concentrations of POA on the growth and proliferation of lymphocytes. Flow cytometry was employed to assess POA's inhibitory effect on T lymphocyte activation triggered by fluorobol ester (PMA) and ionomycin (IM). For evaluating the therapeutic effect of POA on aGVHD, C57bl/c mice were used as donors and BALB/C mice as recipients. The aGVHD mouse model was established to observe the impact of POA on aGVHD treatment, survival, and prognosis.

Results: In vitro experiments demonstrated that POA concentrations ranging from 250uM to 500uM inhibited the proliferation of PMA and IM-activated T lymphocytes and reduced the proportion of CD4+CD25+ cells without causing significant cytotoxicity. The aGVHD mouse model exhibited clinical symptoms like bristling, depilation, anal redness and swelling, and loose stools, along with characteristic pathological changes in the liver and small intestine. Treatment with POA significantly extended the survival period and reduced the clinical score of aGVHD in the model mice.

Conclusion: Palmitoleic acid derived from fish oil shows promise as a potential treatment for acute graft-versus-host disease following allogeneic hematopoietic stem cell transplantation, warranting further research on its immunosuppressive properties.

Keywords: Fish oil extract, palmitoleic acid, acute graft-versus-host disease, allogeneic hematopoietic stem cell transplantation, immunosuppression.