Abstract
Interleukin-11 (IL-11) is a bone marrow (BM) stromal-derived growth factor that has been shown to stimulate murine myeloid and lymphoid cells both in vitro and in vivo and to inhibit adipogenesis in a murine fibroblast cell line. We have studied the effects of IL-11 on highly purified human BM stem and progenitor cells and on human long-term marrow cultures (LTMC). Adipocyte differentiation is an integral component of murine and human LTMC. IL-11 stimulates myeloid growth as a single cytokine when added to highly enriched CD34+, HLA-DR+ bone marrow cells. IL-11 stimulated no growth in the more primitive CD34+, HLA-DR- population even in the presence of additional cytokines. IL-11 addition to human LTMC resulted in the expansion of myeloid and mixed, but not erythroid, progenitor populations. IL-11 dramatically increased the adherent cell populations, including both stromal cells and macrophages. Treated cultures also showed marked inhibition of fat accumulation in the adherent cells due in part to a block in the differentiation of preadipocytes to adipocytes, as shown by RNA analysis using adipocyte-specific markers. These data show that IL-11 stimulates a more differentiated, although multipotential, progenitor cell in human BM and that LTMC provide a useful model for studying the effects of this cytokine in the context of the hematopoietic microenvironment.
Effectiveness evaluation of dendritic cell immunotherapy for osteosarcoma on survival rate and in vitro immune response
