Jurgensen C H, Ambrus J L, Fauci A S
J Immunol. 1986 Jun 15;136(12):4542-7.
Although it has been demonstrated that malignant human B cell lines are capable of producing B cell growth factor (BCGF), production of BCGF by normal B cells has not been shown. In this study, we demonstrate BCGF production by normal B cells, achieved by using human peripheral blood B cells prepared by a positive selection technique and stimulated with Staphylococcus aureus Cowan I (SAC) for 12 hr. SAC was removed from the supernatants by anti-SAC-coupled Sepharose. Supernatants absorbed with this antibody were functionally free of SAC, as demonstrated by their inability to activate resting B cells. B cells stimulated with SAC for 12 hr produced BCGF activity that was generally unmeasurable in supernatants by 36 hr. Characterization of BCGF produced by SAC-stimulated B cells revealed a m.w. of 32,000 by high-performance liquid chromatography sieving and sodium dodecyl sulfate-polyacrylamide gel electrophoresis; this BCGF was found to have an isoelectric point of 6.7. Furthermore, this BCGF lacked interleukin 1, interleukin 2, interferon, and B cell differentiation factor activity. This observation that BCGF can be produced by normal human B cells is significant because it demonstrates for the first time that normal B cells have the ability to provide their own growth factors or the growth factors for other B cells.
虽然已经证明恶性人B细胞系能够产生B细胞生长因子（BCGF），但正常B细胞产生BCGF的情况尚未得到证实。在本研究中，我们证明了正常B细胞能够产生BCGF，方法是使用通过阳性选择技术制备的人外周血B细胞，并用金黄色葡萄球菌Cowan I（SAC）刺激12小时。通过抗SAC偶联的琼脂糖从培养上清中去除SAC。用该抗体吸收后的上清液在功能上不含SAC，这通过它们无法激活静息B细胞得到证明。用SAC刺激12小时的B细胞产生的BCGF活性在36小时时通常在上清液中无法检测到。对SAC刺激的B细胞产生的BCGF进行表征，通过高效液相色谱筛分和十二烷基硫酸钠-聚丙烯酰胺凝胶电泳显示其分子量为32,000；发现该BCGF的等电点为6.7。此外，该BCGF缺乏白细胞介素1、白细胞介素2、干扰素和B细胞分化因子活性。正常人类B细胞能够产生BCGF这一观察结果具有重要意义，因为它首次证明正常B细胞有能力为自身或其他B细胞提供生长因子。
