Studies on the cell phenotype characteristics of hybrid cells crossed between rat nucleated erythroblasts and mouse plasmocytoma (SP2/O) cell line.
The present study is designed to investigate the regulatory effect of mammalian erythroblasts, prior to naturally-occurring denucleation, on malignancy of mouse plasmocytoma cells and the possibility of reactivation of the pyknotic late erythroblast nuclei in hybrid cells crossed between rat intermediate or late erythroblasts of 15-day Wistar rat embryonic livers, and mouse plasmocytoma (SP2/O) cell lines. Results indicated that: (i) Suppression of tumorigenicity and reversion of the malignant phenotype were observed in hybrid cells in a similar way as those of cybrid cells crossed between reticulocytes and myeloma cells as we reported previously, thus providing further evidence to support the hypothesis that some regulatory substances already existed in mammalian intermediate and late erythroblasts long before nuclear extrusion. (ii) Appearance of positive histochemical reaction for hemoglobins in cytoplasm and electrophoretic bands of rat and mouse globin chains in hybrid cell lysate were identified. The transcripts of mouse globin genes could be readily detected by nucleic acid hybridization technique with mouse beta-globin gene probes. (iii) Reassuming of rat chromosome and globin gene products synthesis in hybrid cell indicates that the originally pyknotic nuclei of late erythroblasts could be reactivated to assume functional activity after cell hybridization. The mechanism of regulatory effect and its possible relation to naturally occurring denucleation in developing mammalian red blood cells were discussed.
Zhang
Q Y
QY
Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, Beijing.
Xue
S P
SP
D000818:Animals; D002459:Cell Fusion; D002460:Cell Line; D002869:Chromosome Aberrations; D004900:Erythroblasts / Q000166:cytology / Q000502:physiology*; D015972:Gene Expression Regulation, Neoplastic; D006168:Guinea Pigs; D006822:Hybrid Cells / Q000637:transplantation; D051379:Mice; D008819:Mice, Nude; D010641:Phenotype; D010954:Plasmacytoma / Q000235:genetics* / Q000473:pathology; D051381:Rats; D011919:Rats, Inbred Strains