![Figure 2. Overexpression of Bcl-xL prevents BCR- or arachidonic acid–mediated apoptosis, but not growth arrest, in WEHI-231 immature B cells. Growth arrest was assessed by measurement of anti-Ig- or arachidonic acid–mediated suppression of DNA synthesis by WEHI-231 B cells. (A) WEHI-231-Neo (□) or -Bcl-xL (▪) B cells were treated for 48 hours with 0 to 10 μg/mL anti-IgM or anti-IgM plus anti-CD40 (aIg + aCD40, both at 10 μg/mL), and levels of [3H]-thymidine incorporation into DNA were measured. (B) WEHI-231-Neo (□) or -Bcl-xL (▪) B cells were treated for 48 hours with 0 to 100 μM arachidonic acid or 10 μg/mL anti-IgM, and levels of [3H]-thymidine incorporation into DNA were measured. Data are expressed as means ± SD (n = 3) from single experiments representative of at least 2 other independent experiments. (C) WEHI-231-Neo (□) or -Bcl-xL (▪) B cells were treated for 48 hours with 100 μM arachidonic acid (AA), 10 μg/mL of anti-IgM (aIg), 10 μg/mL anti-CD40 (aCD40), or anti-IgM plus anti-CD40 (aIg/CD40, both at 10 μg/mL), and percentages of apoptotic cells were determined. Data are expressed as means ± SEM and are pooled from up to 13 individual experiments. (D) WEHI-231-Neo (open symbols) or WEHI-231Bcl-xL (filled symbols) B cells were treated for up to 72 hours with medium (squares), 100 μM arachidonic acid (circles), or 10 μg/mL anti-IgM (diamonds) before determining the resulting levels of apoptosis. Apoptosis was measured by propidium iodide (PI) staining of subdiploid DNA content as described in “Materials and methods.”](https://ash.silverchair-cdn.com/ash/content_public/journal/blood/103/1/10.1182_blood-2003-07-2473/6/h80145413002.jpeg?Expires=1735554945&Signature=W~JxSfwuHXZxeF56EIoXJ51NPgbSw4NUs8UL1D4ottfL1yE~sJnhqUh1p9PeDvbJly5Mod-SZ37l7lmPfpV8DV3JymcLnX-eieE7yl0sUcAPiU41h6Zrl358HqQ2fZkeLAKFZu4MCIv5eKbOhgN9q0~XCLVVxEgAPdBKz6TcdfQ0xcDHXNcmw4ieuNlejeJ9lWXOLn4HYBPN7IJqIdSwcUhjdJ6-e52OS6wdiG8j9Ipe0ybuVpO1267YInJ0HYI5DmbDIuhhVPP36dmyCiiGD7aI0I-aC-O6CDI8ybQ6n~~ySy2pUDJgQqeN8R6WpzAtYimDWBagJ8oz7cpveyZ1Zg__&Key-Pair-Id=APKAIE5G5CRDK6RD3PGA)
Overexpression of Bcl-xLprevents BCR- or arachidonic acid–mediated apoptosis, but not growth arrest, in WEHI-231 immature B cells. Growth arrest was assessed by measurement of anti-Ig- or arachidonic acid–mediated suppression of DNA synthesis by WEHI-231 B cells. (A) WEHI-231-Neo (□) or -Bcl-xL (▪) B cells were treated for 48 hours with 0 to 10 μg/mL anti-IgM or anti-IgM plus anti-CD40 (aIg + aCD40, both at 10 μg/mL), and levels of [3H]-thymidine incorporation into DNA were measured. (B) WEHI-231-Neo (□) or -Bcl-xL (▪) B cells were treated for 48 hours with 0 to 100 μM arachidonic acid or 10 μg/mL anti-IgM, and levels of [3H]-thymidine incorporation into DNA were measured. Data are expressed as means ± SD (n = 3) from single experiments representative of at least 2 other independent experiments. (C) WEHI-231-Neo (□) or -Bcl-xL (▪) B cells were treated for 48 hours with 100 μM arachidonic acid (AA), 10 μg/mL of anti-IgM (aIg), 10 μg/mL anti-CD40 (aCD40), or anti-IgM plus anti-CD40 (aIg/CD40, both at 10 μg/mL), and percentages of apoptotic cells were determined. Data are expressed as means ± SEM and are pooled from up to 13 individual experiments. (D) WEHI-231-Neo (open symbols) or WEHI-231Bcl-xL (filled symbols) B cells were treated for up to 72 hours with medium (squares), 100 μM arachidonic acid (circles), or 10 μg/mL anti-IgM (diamonds) before determining the resulting levels of apoptosis. Apoptosis was measured by propidium iodide (PI) staining of subdiploid DNA content as described in “Materials and methods.”
