Kumar A, Vasquez A, Maizel A L, Sharma S
Department of Pathology, Roger Williams General Hospital, Brown University, Providence, RI 02908.
Eur Cytokine Netw. 1990 May-Jun;1(2):109-13.
In case of lymphoid malignancies of B cell origin and Epstein-Barr Virus (EBV) transformed B cells, it is invariably found that these cells proliferate in the apparent absence of signals from T cells. Many of transformed B cells tested appear to be refractory to the proliferative effects of a number of defined cytokines including IL-1, IL-2, IL-4, IL-5, IL-6, IL-7, TNF alpha, lymphotoxin and IFN gamma. We have recently reported on the molecular cloning of a T cell derived human B cell growth factor, BCGF-12kD. In this study, we show that recombinant BCGF-12kD induces proliferation in EBV negative undifferentiated lymphoma B cell line, MC116 and Burkitt's lymphoma B cell line, P3HR1. A mouse monoclonal antibody produced against a BCGF-12kD synthetic peptide neutralizes the BCGF activity present in the MC116 conditioned media as well as inhibits the in vitro growth of MC116. The PCR analysis of the BCGF-12kD gene transcription provides further evidence that MC116 cells express the BCGF-12kD gene, whereas this gene is silent in resting and anti-IgM activated normal human B cells. These data clearly suggest an immunoregulatory role of BCGF-12kD in transformed human B cells.
在B细胞起源的淋巴样恶性肿瘤以及爱泼斯坦-巴尔病毒（EBV）转化的B细胞中，总是发现这些细胞在明显缺乏T细胞信号的情况下增殖。许多被检测的转化B细胞似乎对包括白细胞介素-1、白细胞介素-2、白细胞介素-4、白细胞介素-5、白细胞介素-6、白细胞介素-7、肿瘤坏死因子α、淋巴毒素和干扰素γ在内的多种特定细胞因子的增殖作用具有抗性。我们最近报道了一种T细胞衍生的人B细胞生长因子BCGF-12kD的分子克隆。在本研究中，我们表明重组BCGF-12kD可诱导EBV阴性未分化淋巴瘤B细胞系MC116和伯基特淋巴瘤B细胞系P3HR1增殖。针对BCGF-12kD合成肽产生的小鼠单克隆抗体可中和MC116条件培养基中存在的BCGF活性，并抑制MC116的体外生长。BCGF-12kD基因转录的PCR分析提供了进一步的证据，表明MC116细胞表达BCGF-12kD基因，而该基因在静息和抗IgM激活的正常人B细胞中是沉默的。这些数据清楚地表明BCGF-12kD在转化的人B细胞中具有免疫调节作用。
