Comparison of an Immunoresistant and an Immunosusceptible Ascites Subline From Murine Tumor TA3. I. Transplantability, Morphology, and Some Physicochemical Characteristics2

Abstract

Two ascites lines have evolved from the murine mammary adenocarcinoma TA3. One line, TA3-St, is strain specific and grows preferentially in A/Sn mice. The other line, TA3-Ha, can grow in other strains of mice and has developed immunoresistance without any known selection pressure. The present studies indicate that the ascites TA3-Ha line transgressed all histocompatibility barriers in mice tested, even at low cell inocula, and also grew in some xenogeneic hosts. Cytological examination revealed some similarities, but marked differences in karyotypes were found. Electron microscope scans indicate that TA3-Ha cells had a smoother membrane surface structure than TA3-St cells. The near-diploid TA3-Ha line grew slightly faster than the aneuploid TA3-St line in A/Sn mice; this finding was based on the total assessable cell number per mouse, as well as the calculated total tumor-cell mass. TA3-Ha cells had a higher electrophoretic mobility than TA3-St cells, indicating a higher net-negative surface charge of the former. TA3-Ha cells were not agglutinated by the plant lectin Concanavalin A, in contrast to TA3-St cells and all other murine ascites tumors tested.