Abstract: The invention provides a method of culturing mononuclear cells, comprising isolating mononuclear cells from the blood or cell-containing fluids of the body of a mammal; culturing the cells in a culture medium comprising one or more of gangliosides, phospholipids, glycolipids and growth factors for endothelial cells. These cells are useful, for example, for the endothelialization of injured vessels. The invention also provides a method of making cells capable of expressing a biologically active protein, comprising isolating mononuclear cells from the blood or cell-containing fluids of the body of a mammal; culturing the cells in a culture medium comprising one or more of gangliosides, phospholipids, glycolipids and growth factors for endothelial cells; optionally, before or after culturing the cells, immortalizing the cells; and transfecting the cells with a nucleic acid construct comprising a gene for the biologically active protein.

Abstract: The present invention relates to a process for determining complexes of .alpha.-1-antichymotrypsin and cathepsin G in a sample comprising adsorbing the cathepsin G portion of the complex to a solid phase coated with non-specific binding protein or gelatin, and detecting the .alpha.-1 portion of the complex with a detectably labelled anti-.alpha.-1-antichymotrypsin antibody. A diagnostic kit comprising the solid phase coated with non-specific binding protein or gelatin and the labelled anti-.alpha.-1-antichymotrypsin antibody is also provided.