Peripheral versus Marrow Lipidomics in Patients with Severe Aplastic Anemia: Potential Indicators for Early Immunosuppressive Treatment Response

This study aimed to explore the differences of peripheral blood (PB) and bone marrow serum lipidomic profiles in severe aplastic anemia (SAA) patients and their significance in predicting earlier immunosuppressive therapy (IST) response. A cohort of 11 newly diagnosed SAA patients and 15 healthy controls were enrolled between June 2020 and November 2022, and six of the SAA patients received ATG-based IST. PB and BM serum were collected for further LC-MS/MS analysis. Compared to donors, SAA patients exhibited more pronounced abnormalities in lipid metabolism profiles within BM serum relative to PB serum. Specifically, elevated levels of free fatty acids (FA), fatty acid esters of hydroxyl fatty acids (FAHFA), and phosphatidylserine (PS) were noted in the BM serum of SAA patients. Following treatment, there was a noted increase in acylcarnitine (ACar), hexosylceramide non-hydroxy fatty acid-sphingosine (HexCer-NS), and sulfur hexosyl ceramide hydroxy fatty acid (SHexCer), while levels of lysophosphatidylcholine (LPC) and oxidized phosphatidylcholine (OxPC) diminished, particularly in complete or partial response (CR/PR) patients. Acknowledging the changes of BM lipidomics may contribute to earlier prediction of ATG-based IST response in SAA patients.