CD14 and hydrops fetalis: This study did not conduct further experimental researches on the mechanisms for the reduction of CD14+ monocytes in peripheral blood, but we found that heterogeneous information on CD14+ monocytes may serve as a crucial indicator/biomarker to evaluate whether HF patients are suitable for MSC treatment because different subgroups of CD14+ monocytes exhibit functional enrichment in different physiological processes, and some functional enrichment pathways are closely related to the mechanisms of MSC treatment, which helps explain the effectiveness of MSC therapies.