亲代L7811及体外培养小鼠白血病细胞系L7811—85...

Ultrastructural studies of parental (L7811) and in vitro cultured (L7811-85) murine leukemic cell lines

L7811 was an ascitic form of lymphocytic leukemia induced by myleran in 615 mice. Under electron microscope, cytoplasmic and intracisternal type A virus-like particles were observed. L7811-85 was a cell line established in vitro from the parental in vivo L7811 line. Instead of type A particles, mature and immature type C murine virus-like particles could be observed budding from the plasma membrane to extracellular space. With the in vitro subpassage of L7811-85 cells, more intracellular and extracellular type C particles appeared with an increase in its tumorigenicity. When L7811-85 cells, were inoculated IP to normal 615 mice, ascites tumor developed. The type A virus particles appeared again budding into cisterna of endoplasmic reticulum but not to extracellular space. The mechanism of virus particle type transformation remains to be studied.