Abstract: Method for obtaining and expanding postembryonic hematopoietic stem cells from umbilical cord blood while avoiding unwanted differentiation. Initial cells from umbilical cord blood are proliferated and multiplied ex vivo in a stroma-free medium and in the presence of a regio-modified glycan or glycosaminoglycan. The regio-modified glycan or glycosaminoglycan, e.g. a heparin derivative, is N-desulfated, and N-reacetylated or N-reacylated, in essence, on C2 atoms. The heparin derivative advantageously comprises less than 5 percent of C3-O-sulfate, at least 60 percent C2-O-sulfate, and it is preferably added in a quantity of 15 to 50 mg/L to the medium in order to stop an unwanted differentiation. The stem cells generated in this manner can differentiate, after expansion, into myeloma cells and lymphatic cells, and they can be used as an immunotherapeutic agent against many diseases.

Abstract: The invention is related to methods for expanding and differentiating hemopoietic progenitor cells in a medium comprising a collection of cytokines, desulphated glycosaminoglycan and human serum. The invention further relates to a collection of cells obtainable by a method of the invention, use of the collection of cells, and a kit of parts for expanding and differentiating hemopoietic progenitor cells.

Abstract: The invention provides means and methods for stem cell proliferation and subsequent generation and expansion of progenitor cells. The invention in particular provides media and other culture conditions for the same. The cells are preferably used as effector cells as clinical therapeutics.

Abstract: The present invention relates to the ex vivo differentiation of NK cells from CD34+ hematopoietic stem cells. Such NK cells and their progenitor cells can be used in therapies of a broad range of malignancies. In the present invention it is shown that IL-12 modulates ex vivo NK cell differentiation. Specific, we achieved significantly higher expression of KIR, CD16 and CD62L in the presence of IL-12 in the cell culture system. The induction of receptor expression by IL-12 occurred predominantly on an augmented population of CD33+NKG2A+ NK cells early during NK cell differentiation. These cells further show enhanced cytolytic activity against MHC class I positive AML targets. In line with the enhanced CD16 expression, IL-12 modulated ex vivo generated NK cells exhibit an improved antibody-dependent-cytotoxicity, using anti CD20 antibody on various B cell targets. Additional to the enhanced expression of CD62L, we show that this cell population consists of a specific chemokine receptor profile.