Assessing the condition of the structural proteins of cardiomyocytes in patients with various forms of cardiomyo- pathy (49 samples) revealed changes characteristic for dilated cardiomyopathy, as well as common disorders of the molecular structure, developing, regardless of the etiology of the disease.

Abstract. A combination of fluorescent staining with Hoechst 33342 dye, and flow cytometry of murine bone marrow cells may be used for separation of a side population (SP), which is highly enriched for hematopoietic stem cells capable of long-term hematopoietic reconstitution in lethally irradiated recipients. Recently, this approach was also applied to analysis of SP cells in several types of non-hematopoietic tissues, and malignant tumours. In spite of yet poor definition of phenotype and functional potency of SP cells from various tissues, the method of SP isolation may be a useful tool for analysis and pre-enrichment of stem cell-like cells of different origin. Present review article presents a brief description of Hoechst 33342-staining approach, and of recent reports concerning SP studies in various normal and malignant tissues. (Med. Immunol., vol. 10, N 4-5, pp 319-326).