Characterization of monoclonal nonspecific suppressor factor (MNSF) with the use of a monoclonal antibody.

在我们以前的研究中，我们试图制备一个杂交瘤产生的单克隆非特异性抑制因子（MNSF）。我们试图定义其生化特性，然后将其与已经报道的非特异性抑制因子进行比较。该MUSF抑制脂多糖（LPS）诱导的免疫球蛋白（IG）分泌细胞的产生。本研究制备了抗MNSF的单克隆抗体。命名为MO6的单克隆抗体识别具有特异性反应性的MNSF。MO6消除了MNSF的抑制作用，而针对不相关抗原的鼠IgG单克隆抗体没有这种作用。这些结果表明，MO6结合MNSF的功能活性位点，从而阻断生物活性。免疫印迹分析表明，MO6与16，000和24，000道尔顿的MNSF反应，从而表明这些物种在功能和免疫学上是相同的。本文对从刀豆蛋白A（ConA）激活的人外周血单个核细胞培养上清中检测人非特异性抑制因子（HNSF）进行了探索性尝试。从MO6亲和柱层析获得的结合级分显示抑制剂活性。这一结果表明在Con A活化的上清液中存在抑制因子，其在生物活性方面与鼠MNSF相同。纯化后的HNSF与小鼠MNSF具有相似的分子量。和物理化学性质。我们用MO6抗体建立了检测MNSF抗原的ELISA体系。并对MNSF的N端氨基酸序列进行了分析。该信息将是分离编码MNSF的cDNA的相关探针。

In our previous study, we attempted to prepare a hybridoma producing a monoclonal nonspecific suppressor factor (MNSF). We attempted to define its biochemical characteristics, and then to compare it with already reported nonspecific suppressor factors. This MUSF inhibits the generation of lipopolysaccharide (LPS) induced immunoglobulin (Ig)-secreting cells. In the present study, we made a monoclonal antibody toward MNSF in murine system. The monoclonal antibody designated MO6 recognizes MNSF with specific reactivity. MO6 abrogates the suppressive effect of MNSF, whereas the murine IgG monoclonal antibodies against irrelevant antigens have no such effect. These results indicate that MO6 binds the functionally active site of MNSF and consequently block the biological activity. Immuno-blotting analysis showed that MO6 reacts with MNSF of 16,000 and 24,000 daltons, thereby, indicating that these species are identical, both functionally and immuno-logically. An explorative attempt was made to detect human nonspecific suppressor factor (HNSF) from the culture supernatant of Con A activated human peripheral blood mononuclear cells. The bound fraction obtained from the MO6 affinity column chromatography showed suppressor activity. This result indicates the existence of a suppressor factor in Con A activated supernatant, which is identical with murine MNSF in terms of biological activity. The purified HNSF shows charac-teristics similar to murine MNSF, that is, both have similar m.w. and physioc-chemical properties. We developed a ELISA system with the use of MO6 antibody in order to detect MNSF antigen. Furthere, N-terminal amino acid sequence of MNSF were analyzed. This information will be a pertinent probe for isolating the cDNA that encodes for MNSF.