Abstract: The discovery of Toll-like receptors (TLRs) on the surface of hematopoietic cells provides new methods for the stimulation and differentiation of various classes of progenitor cells. TLR2 and TLR4 agonists (natural ligands, mimetics, antibodies) are particularly useful in these methods. The cells can be isolated and used for various purpose including tissue regeneration and grafting. In contrast, antagonists of TLRs can be used to protect cells from various insults such as chemo- and radiotherapy, acute and chronic infection, and transplantation by inhibiting activation and differentiation. TLR2, TLR4 and TLR9 pathway antagonists (soluble TLR, mimetics, antibodies) are particularly useful in these methods. Cells can be isolated and used for various purposes including transplantation.

Abstract: A novel protein having the activity to suppress proliferation of lympho-hematopoietic cells derived from BNS2.4 cells, its gene, a method for preparing them and their uses are provided. The novel protein has been identified from a stromal cell line BMS2.4 by expression cloning targeting mouse myelomonocytic leukemia cell line WEHI3. This protein and its gene are useful for treating lympho-hematopoietic disorders.

Abstract: A novel protein having the activity to suppress proliferation of lympho-hematopoietic cells derived from BNS2.4 cells, its gene, a method for preparing them and their uses are provided. The novel protein has been identified from a stromal cell line BMS2.4 by expression cloning targeting mouse myelomonocytic leukemia cell line WEHI3. This protein and its gene are useful for treating lympho-hematopoietic disorders.

Abstract: The stromal cells that support blood cell production within bone marrow are pre-adipocytes and functional interactions with marrow fat cells have long been suspected. Adiponectin was recently isolated as an adipocyte product and shown to have structural similarities to Clq as well as members of the TNF superfamily. It suppresses myeloid differentiation in short term bone marrow cultures and also inhibits macrophage functions. These observations raised the possibility that precursors of other blood cell lineages interact with fat cells in marrow via adiponectin. It has now been determined that the factor blocks B lymphopoiesis in Whitlock-Witte type bone marrow cultures, but not the production of myeloid cells in Dexter cultures. Several observations suggest that non-lymphoid cells represent the target of this new mediator, and the B lymphoid lineage is only indirectly influenced. Highly purified lymphocyte precursors in stromal cell-free, serum-free cultures were unaffected by adiponectin.

Abstract: Based on the discovery that normal pregnant mice have a striking reduction in committed precursors of B lymphocytes, which could be documented in mice as early as day 6 of gestation, when IL-7 responding colony forming cells were reduced as much as two-thirds of normal levels, it has been determined that estrogen and other hormones elevated in pregnancy induce a specific modulation of lymphocyte formation during pregnancy and lactation. It is therefore possible to immunomodulate in a specific manner an animal by administration of hormones elevated during pregnancy, such as estrogen and estrogen-like compounds, or antagonists of estrogen. This has potential in the treatment of a number of disorders, especially those found in very high percentages of women as compared with men, such as many of the autoimmune disorders, as well as in immune tolerance during pregnancy, cyclic neutropenia, and osteoporosis.

Abstract: It has been determined that estrogen and other hormones elevated in pregnancy induce a specific modulation of lymphocyte precursor cell production. The immune system of an animal or bone marrow cells in culture can therefore be modulated in a specific manner by administration of hormones elevated during pregnancy, such as estrogen and estrogen-like compounds or compounds that interfere with the synthesis or activity of these hormones, to increase or decrease production of B lymphocyte precursor cells.