Joseph LoBue

THE LYMPHOCYTES OF CHRONIC LYMPHOCYTIC LEUKEMIA: THEIR PROLIFERATION AND CELL CYCLE KINETICS

Lymphocytes obtained from CLL patients exhibited a delayed and reduced response to PHA when cultured in diffusion chambers. DNA synthesis (8–10 hr) and general time (15–19 hr) of the late‐developing CLL blasts were consistent with normal values (Ts: 8–10 hr; Tc: 14–17 hr). However, the G2 period of CLL blasts seemed more variable, and their mitotic index during the response at 5–6 days was 30–50% of the values determined for normal blasts during their peak response at 2–3 days.

Autoradiographic Studies of Human Lymphocytes Cultured in Vivo

Summary Human lymphocytes were cultured in diffusion chambers implanted into the peritoneal cavities of rats. In cultures treated with PHA, the pattern of morphologic transformation and initiation of DNA synthesis paralleled closely similar studies made in vitro. Immunologic stimulation of the human cells by the heterologous host was presumably minimal or absent since control cultures (without PHA) showed no significant degree of blastogenesis when compared with PHA-treated cultures. Minimum DNA synthesis time determined for the PHA-stimulated lymphocytes was 9–10 hr. Values found for the duration of Tc (16–18 hr) and minimum TG2 (2 hr) were shorter than those reported for similar studies in vitro. The in vivo culture method using Millipore chambers appears to offer a more physiologic method for studying lymphocytes.

Growth Characteristics of the Shay Chloroleukemia in Diffusion Chambers

Summary Chloroleukemic cells placed within diffusion chambers grew at a fairly uniform rate in both rats and mice. Both mitotic indices and mitotic times (about 40 min) were the same in all chambers regardless of the number of cells in the initial population. The numbers of cells declined moderately during the first 48 hr and increased slowly until harvest on Day 7.