title: Do human spermatozoa reactivate in the cytoplasm of somatic cells?
abstract: The morphological changes following Sendai virus-enhanced interaction of purified fractions of human spermatozoa with various types of fibroblast lines were examined over a period of several days. The incorporation of spermatozoa was monitored by a variety of immunofluorescent staining techniques, including one for protamin. The initially high incorporation frequency (30--40%) was accompanied by swelling of the acrosome and nucleus, which, in most instances, was followed by gradual lysis of the sperm components. However, a small proportion of all incorporated spermatozoa (2%) exhibited chromatin decondensation, accompanied by a shift from a protamin to histone content and induction of RNA and DNA synthesis. These latter cells appear to fit the criteria for true reactivation and electron-microscope studies show that they do not undergo phagocytosis as do the majority of incorporated spermatozoa.
mesh_terms: D002459:Cell Fusion; D003593:Cytoplasm / Q000648:ultrastructure; D004247:DNA / Q000096:biosynthesis; D005347:Fibroblasts / Q000648:ultrastructure*; D005455:Fluorescent Antibody Technique; D006579:Heterozygote; D006657:Histones / Q000096:biosynthesis; D006801:Humans; D066298:In Vitro Techniques; D008297:Male; D008854:Microscopy, Electron; D012313:RNA / Q000096:biosynthesis; D013094:Spermatozoa / Q000378:metabolism / Q000648:ultrastructure*
chemical_list: D006657:Histones; D012313:RNA; D004247:DNA