Leftwich J A, Hall R E
Laboratory of Tumor Immunology, Guthrie Clinic/Medical Center, Sayre, Pennsylvania 18840-1692.
Cancer Res. 1989 Aug 15;49(16):4459-65.
In this report, we present the further characterization and purification of a cytokine differentiation factor, termed P48, which unlike previously described differentiation factors is antigenically unrelated to tumor necrosis factor alpha (TNF-alpha), tumor necrosis factor beta (TNF-beta), and gamma interferon. HL-60 cells and phorbol diester-resistant HL-60-1E3 cells exposed to conditioned medium from Reh cells mature along the monocyte/macrophage pathway, as assessed by several assays (express nonspecific esterase, produce superoxide anion, morphologically resemble monocytes, mediate phorbol diester-triggered extracellular cytolytic activity). Reh cell conditioned medium is antiproliferative toward a panel of cell lines, is not nonspecifically cytotoxic, has no antiviral or colony-stimulating factor activities, and is not affected by exposure to insolubilized anti-gamma interferon. A 48-kDa glycoprotein (P48) which mediates this differentiation factor activity has been purified to homogeneity from Reh cell conditioned medium, and a polyclonal neutralizing antiserum has been produced. P48 activity is not blocked by either anti-TNF-alpha and anti-TNF-beta and on Western blot analysis is antigenically distinct from TNF-alpha and TNF-beta. In addition, polyclonal anti-P48 does not block either TNF-alpha or TNF-beta activities or recognize either on Western blots. Unlike gamma interferon, colony-stimulating factor, TNF-alpha, or TNF-beta, P48 reverses phorbol diester resistance of HL-60-1E3 cells. These studies present strong evidence for the existence of a previously unrecognized cytokine which, unlike other reported differentiation factors, is antigenically unrelated to TNF-alpha or TNF-beta. P48 may play an important role in growth and development of normal and abnormal (leukemic) hematopoietic and nonhematopoietic cells.
在本报告中，我们展示了一种细胞因子分化因子（称为P48）的进一步特性鉴定和纯化过程。与先前描述的分化因子不同，P48在抗原性上与肿瘤坏死因子α（TNF-α）、肿瘤坏死因子β（TNF-β）和γ干扰素无关。通过多种检测方法评估（表达非特异性酯酶、产生超氧阴离子、形态上类似于单核细胞、介导佛波酯触发的细胞外溶细胞活性），暴露于Reh细胞条件培养基中的HL-60细胞和对佛波二酯耐药的HL-60-1E3细胞沿单核细胞/巨噬细胞途径成熟。Reh细胞条件培养基对一组细胞系具有抗增殖作用，无非特异性细胞毒性，无抗病毒或集落刺激因子活性，且不受暴露于不溶性抗γ干扰素的影响。一种介导这种分化因子活性的48 kDa糖蛋白（P48）已从Reh细胞条件培养基中纯化至同质，并制备了多克隆中和抗血清。P48活性不受抗TNF-α和抗TNF-β的阻断，在蛋白质印迹分析中，其抗原性与TNF-α和TNF-β不同。此外，多克隆抗P48既不阻断TNF-α或TNF-β的活性，也不在蛋白质印迹中识别它们。与γ干扰素、集落刺激因子、TNF-α或TNF-β不同，P48可逆转HL-60-1E3细胞对佛波二酯的耐药性。这些研究为一种先前未被认识的细胞因子的存在提供了有力证据，该细胞因子与其他报道的分化因子不同，在抗原性上与TNF-α或TNF-β无关。P48可能在正常和异常（白血病）造血及非造血细胞的生长和发育中发挥重要作用。
