Action mechanism in vitro of sensitized regional lymph node cells on target cell. I. Anti-growth effect of regional lymph node cells of Ehrlich cancer transplanted mouse and that of normal lymph node cells induced by PHA, on Ehrlich cancer cell line (JTC-11)

Under in vivo conditions JTC-II cells derived from Ehrlich ascites　tumor are led to destruction by lymph node cells by two processes. The　one is the interaction of lymph node cells of the C57BL (♀) mouse sensitized with Ehrlich ascites tumor cells, and the other is the interaction of　normal C57BL (♀) mouse lymph node cells treated with PHA-M. In　these two reaction systems the following differences have become clear. The regional lymph node cells from the C57BL (♀) mouse sensitized　with Ehrlich ascites tumor cells show a marked inhibitory effect on the　growth oflTC-II cells by 10 days after sensitization.　In the observations under the phase contrast microscope these lymph node cells tend to adhere around the antigenic cells by culture hour 5-6, and by culture hour 24-48 they lead the latter to undergo cytolysis. The normal lymph node cells of C57BL (♀) mouse treated with PHA show anti-growth effect oflTC-II cells. PHA-M used proves to be effective in the concentration of 2% (v/v). Likewise after such normal lymph node cells are previously treated with 2% PHA-M for 12 hours, they also inhibit the growth of lTC-II cells when two cell groups are cultured together. In such intercellular reaction between the two cell groups there is no specificity. By observations under the phase contract microscopy, by culture hour 2-3 the adherence and aggregation of lymph node cells begin to occur, and by 18-24 hours of culture the target cells are led to undergo cytolysis. In this instance, lymph node cells are prone to adhere and aggregate on one side of the target cell.