Klostergaard J, Foster W A, Hamilton D A, Turpin J, Lopez-Berestein G
Cancer Res. 1986 Jun;46(6):2871-5.
Human peripheral blood monocytes, isolated in high purity by centrifugal counterflow elutriation from normal donors, release cell toxins, herein termed human monocyte toxins (HMTs) upon further stimulation in vitro. The principal form of HMTs produced by these human peripheral blood monocytes has been subjected to biochemical, functional, and serological characterization. By molecular sieving on Sephacryl S-200, HMTs can be resolved into two molecular weight classes. The larger, termed alpha, has a molecular weight of about 120,000, and the smaller, termed beta, has a molecular weight of about 65,000. The beta class is by far the most predominant species and has been further characterized. Chromatofocusing of beta-HMT indicates a slightly acidic nature, since this species is eluted at pH 5.8. Functional characterization of beta-HMT suggests that it is not a trypsin-like protease, since neither alpha,N-tosyl-L-lysylchloromethylketone nor alpha,N-tosyl-L-arginyl methyl ester are capable of causing significant inhibition of the cell-lytic activity of the molecule. Furthermore, cell lysis induced by beta-HMT appears to be independent of oxygen-dependent mechanisms, since catalase is incapable of blocking lysis, and since hydrogen peroxide and superoxide anion are not produced in detectable amounts during lysis. Finally, beta-HMT does not appear to be an arginase, since it is active in arginine-containing medium and further addition of arginine to the assay medium does not inhibit lysis significantly. beta-HMT is serologically related to recombinant human tumor necrosis factor (rHuTNF), since its cell lytic activity can be blocked by a rabbit antiserum against rHuTNF. However, much higher levels of this antiserum are required to achieve neutralization than are required to neutralize a comparable number of cell lytic units of rHuTNF. Furthermore, the results of preliminary immunoprecipitation experiments using the rabbit anti-rHuTNF antiserum suggest that a peptide in the Mr 60,000-70,000 range is recognized by this serum, whereas no signal at Mr 17,000 corresponding to rHuTNF is detectable. Thus, human peripheral blood monocytes can be triggered to release cell toxins, the principal form of which, beta-HMT, appears to be functionally distinct from the cytotoxic proteases reported in the murine system and appears to be molecularly distinct from, but serologically related to rHuTNF.
通过离心逆流淘析法从正常供体中高纯度分离得到的人外周血单核细胞，在体外进一步刺激后会释放细胞毒素，在此称为人单核细胞毒素（HMTs）。这些人外周血单核细胞产生的HMTs的主要形式已进行了生化、功能和血清学特性分析。通过在Sephacryl S - 200上进行分子筛分离，HMTs可分为两个分子量类别。较大的称为α，分子量约为120,000，较小的称为β，分子量约为65,000。β类是迄今为止最主要的种类，并已进一步进行了特性分析。β - HMT的色谱聚焦显示其具有微酸性性质，因为该种类在pH 5.8时被洗脱。β - HMT的功能特性表明它不是一种类胰蛋白酶，因为α - N - 甲苯磺酰 - L - 赖氨酰氯甲基酮和α - N - 甲苯磺酰 - L - 精氨酰甲酯都不能显著抑制该分子的细胞裂解活性。此外，β - HMT诱导的细胞裂解似乎与氧依赖机制无关，因为过氧化氢酶不能阻断裂解，并且在裂解过程中未检测到过氧化氢和超氧阴离子的产生。最后，β - HMT似乎不是一种精氨酸酶，因为它在含精氨酸的培养基中具有活性，并且向测定培养基中进一步添加精氨酸不会显著抑制裂解。β - HMT与重组人肿瘤坏死因子（rHuTNF）存在血清学相关性，因为其细胞裂解活性可被抗rHuTNF的兔抗血清阻断。然而，与中和相当数量的rHuTNF细胞裂解单位相比，需要更高水平的这种抗血清才能实现中和。此外，使用兔抗rHuTNF抗血清进行的初步免疫沉淀实验结果表明，该血清可识别分子量在60,000 - 70,000范围内的一种肽，而未检测到对应于rHuTNF的17,000分子量处的信号。因此，人外周血单核细胞可被触发释放细胞毒素，其主要形式β - HMT在功能上似乎与小鼠系统中报道的细胞毒性蛋白酶不同，并且在分子上似乎与rHuTNF不同，但存在血清学相关性。
