CD257 does not affect cell proliferation but enhances survival of leukemia cells. (A) Proliferation of CD3⁻CD5⁺ lymphocytes obtained from TCL1-Tg or TCL1×BAFF-Tg mice was measured by BrdU incorporation. For this, mice were pulsed with BrdU and 12 hours later splenocytes were collected and stained with anti-BrdU. Mouse immunoglobulin G was used as an isotype control for anti-BrdU. Splenocytes from TCL1-Tg and TCL1×BAFF-Tg mice were gated for CD3⁻CD5⁺ and analyzed by flow using anti-BrdU. Results are from triplicate experiments (n = 3 mice each strain). (B) Ki-67 antibody stainings. Cells were obtained and gated as in panel A and stained for intracellular Ki-67 expression. Mouse immunoglobulin G was used as isotype control for anti–Ki-67. Results are from triplicate experiments (n = 3 mice each strain). (C-D) Frozen splenic sections of mouse strains indicated were stained for TUNEL-TMR-Red. Data shown were average of relative TUNEL-positive cells from splenic sections (n = 5 mice). Magnification of the objective lense: 20×/0.50 Camera: Zeiss AxioCam HR. Software: AxioVs40AC v4.5.0.0.