Bone marrow stromal cells are essential for maintaining a favourable microenvironment for cell regeneration and differentiation. Extensive studies are exploring how these cells influence the gene regulation of haematopoietic stem cells and other bone marrow cells. The molecular mechanisms underlying the immunomodulatory effect of stromal cells are the subject of intensive research. This includes studying the molecular interactions between stromal cells and cells of the immune system, as well as understanding the signalling pathways involved. Interactions between stromal cells and other bone marrow cells, including haematopoietic stem cells, are an important area of research. This includes the study of cell adhesions, paracrine signalling and specific molecular interactions.