CD8A and hydrops fetalis: aDCs, cytolytic activity, CD8+ T cells, HLA, iDCs, inflammation-promoting, NK cells, type I IFN response, mast cells, Th1 cells, and T cell co-stimulation showed high expression in the HF group, whereas B cells, APC co-inhibition, checkpoint, CCR, macrophages, pDCs, T cell co-inhibition, Tfh, and Treg were less expressed in the HF group.