Abstract: The objects of the present invention are to solve low test efficiency and low accuracy which are problems encountered in the conventional methods for testing myelotoxicity of a drug by observing smears. To this end, markers for discriminating and identifying hematopoietic stem cells and blood cells at various differentiation stages in bone marrow are identified. From this point of view, cell surface antigens are specified. Thus, it is found that the myelotoxicity of a drug can be evaluated with a high efficiency at a high accuracy by using flow cytometry to analyze for a change in the quantity of bone marrow-derived cells expressing the cell surface antigens after administration of the drug to an animal.

Abstract: The subjects of the present invention are to solve low test efficiency and low accuracy which are problems encountering in the conventional methods for testing myelotoxicity by observing smears.

Abstract: This invention provides a monoclonal antibody or its fragment specific to a human .alpha..sub.2 -plasmin inhibitor, said antibody having the function of specifically blocking that site of the human .alpha..sub.2 -plasmin inhibitor which inhibits the fibrinolytic activity of plasmin, and of suppressing said fibrinolytic activity inhibiting function of said .alpha..sub.2 -plasmin inhibitor, and also a hybridoma capable of producing the monoclonal antibody. Said monoclonal antibody or its fragment is useful for the immunological determination of a human .alpha..sub.2 -plasmin inhibitor, the separation or recovery of a human .alpha..sub.2 -plasmin inhibitor from a liquid containing the human .alpha..sub.2 -plasmin inhibitor, and the treatment of a thrombotic disease.

Abstract: In methods for immunologically assaying free lipoprotein associated coagulation inhibitor (hereafter abbreviated as "LACI") in a human inspection sample using a first antibody immobilized on an insoluble carrier and a labeled second antibody, a method for immunological assay of free LACI and a kit therefor wherein(i) any one antibody of the first antibody and the second antibody is a monoclonal antibody recognizing the polypeptide (K3) of the following amino sequence ##STR1## (hereafter referred to as a "K3-antibody"), and (ii) the other antibody is a monoclonal antibody recognizing the polypeptide (K1) of the following amino acid sequence ##STR2## (hereafter referred to as a "K1-antibody").

Abstract: A method of immunologically determining free human protein S in an assay sample, which comprises contacting a primary antibody fixed to an insoluble solid carrier and a labelled secondary antibody with the assay sample, the primary and secondary antibodies having the property of binding to different epitopes of free human protein S, and one of the primary and secondary antibodies being a monoclonal antibody having the property of not binding to a complex of the human protein S and human complement cofactor C4b-binding protein (C4bp) but specifically binding to the free human protein S.