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Background: The increasing use of autologous hematopoietic cell support in various malignancies including leukemia and lymphoma currently bears the problem of tumor contamination of the graft with tumor cells which after re-infusion contribute to the disease relapses. It is therefore desirable to eradicate the cancer cell fraction of the graft without causing damage to the normal stem cell fraction. The purging processes based on photodynamic treatments appear to be perspective means for this purpose., Methods and Results: We investigated the effects of 5-aminolevulinic acid (ALA)--based photodynamic treatment (ALA-PDT) on the proliferation of human leukemia cell lines HL60 (promyelocytic leukemia), ML2 (myelomonocytic leukemia) and HEL (erythroleukemia) by 3H-thymidine incorporation into the cell DNA, on the viability of cell lines HL60, HEL, DAUDI (B-cell leukemia) and JURKAT (T-cell lymphoma) as well as of blast cells of acute myeloid leukemia (AML) patients by flow cytometry-propidium iodide assay, and on the clonogenic activities of normal human bone marrow cells by in vitro cloning assays. Under the conditions used (treatment with 1 mM ALA for 4 h at 37 degrees C followed by exposure to blue light dose of 18 J/cm2) the number of proliferating HL60 cells was reduced by 2.4 logs, of ML2 cells by 3.2 logs and of HEL cells by 1 log. From the mononuclear cell preparations of AML patients the blast cells were substantially reduced in eight out of ten patients. The clonogenic activities of normal bone marrow progenitor cells were largely spared: 52.5 +/- 8.9% of colony-forming units--granulocytes macrophages (CFU-GM), and 48.6 +/- 9.7% burst forming units--erythrocytes (BFU-E)., Conclusions: ALA-PDT appears to be usable principle for the depletion of residual leukemic cells from autologous transplants.

Background: Residual leukemic cells if present in autologous bone marrow grafts or CD34+ concentrates obtained from peripheral blood may increase the risk of relapse after autotransplantation. We are presenting the employment of a new method which was introduced into the photodynamic therapy, namely enhancement of synthesis of the photosensitizing compound, protoporphyrin IX, in cancer cells, following application of its metabolic precursor, 5-aminolevulinic acid, for the specific destruction of leukemic cells., Methods and Results: By determining cell viability using tetrazolium salt reduction (MTT), by flow cytometrypropidium iodide assay and by determining cell proliferation using bromodeoxyuridine incorporation we studied the effect of photodynamic therapy based on the application of 5-aminolevulinic acid on the cells of leukemic cell lines HL60 (human promyelocytic leukemia), HEL (erythroleukemia), DAUDI (B-cell leukemia), JURKAT (T-cell lymphoma), blast cells of patients with acute myelogenous leukemia as well as on normal lymphocytes and normal human bone marrow progenitors. In in vitro experiments photodynamic therapy based on an administration of 5-aminolevulinic acid (1 mM, 4 h, 18 J/cm2) lowered the number of viable leukemic cells by over 2 orders (with the exception of HEL cells) and eliminated blast cells in mononuclear cell preparations of six out of seven patients with acute myelogenous leukemia. On the other hand the viability of normal resting lymphocytes was little affected by photodynamic therapy (number of necrotic cells increased from 6 to 11%) and also the clonogenic activity of the progenitor cells of normal bone marrows did not decrease substantially (CFU-GM to 60% and BFU-E to 55% of the original activity)., Conclusions: Photodynamic therapy based on the application of 5-aminolevulinic acid is a perspective method for the specific destruction of leukemic cells in autologous transplants.

Principles and mechanisms of the photobiological effects of porphyrin derivatives on the cell components and their employment for the selective destruction of cancer tissues (photodynamic therapy) are discussed. The present status of the photodynamic therapy for the treatment of various cancers is given.

The article is devoted to the coagulation proteinases inhibitor antithrombin III which plays an important role in the processes of blood coagulation. The molecular and gene structure, physiology and pathophysiology, assays and therapeutical meanings are dealt with.

Human serum haemopexine together with albumin participates in the removal of haemoglobin released into the circulation during intravascular haemolysis by a haeme bond and in its transport into parenchymal liver cells.

A method is described of the isolation of monoclonal antibodies form mouse ascites fluids by chromatography on beaded DEAE cellulose with covalently bound Reactive Blue-2 ("Blue" DEAE cellulose). The method yields antibodies of 80-90% purity, free from protease activity.