Abstract:
The present invention provides a cytokine-based culture method for ex vivo expansion of NK cells from postembryonic hematopoietic stem cells into a fully closed, large-scale, cell culture bioprocess. We optimized enrichment of CD34 + cells followed by efficient expansion in gas-permeable cell culture bags. Thereafter, expanded CD34 + cells could be reproducibly amplified and differentiated into CD56 +CD3- NK cell products with a mean expansion of more than 2,000 fold and a purity of >90%. Also provided are collections of cultured cells having specific properties.
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. By showing an increased capacity for adhesion to lymphendothelial cells and a specific chemokine receptor profile, we show that IL-12 provided the ex vivo generated NK cells with specific tissue-homing abilities.
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.