Tominaga A, Takatsu K, Hamaoka T
J Immunol. 1982 Jun;128(6):2581-5.
An in vitro experimental system was established to demonstrate the TRF-substituting activity of an alloantiserum raised in TRF low-responder (DBA2/2Ha x BALB/c)(DC)F, male mice against TRF high-responder parental BALB/c B cells. The TRF substituting activity of the antiserum was apparent in that anti-Thy-1 plus C-treated, DNP-primed B cells from TRF high-responder mice were effectively stimulated, whereas B cells from TRF low-responder DBA/2Ha mice were not, as evidenced by the induction of secondary anti-DNP IgG PFC responses. The specificity of the reaction of the antibody with a component present on the TRF high-responder B cells was also substantiated by the fact that antibody activity was virtually eliminated by absorption with B cells from various TRF high-responder mice but not by TRF low-responder DBA/2Ha B cells. The IgG fraction of antiserum and the F(ab')2 and Fab' fragments of the antibody, which possess a comparable reactivity in regard to the TRF acceptor site(s), were prepared, and analysis of the B cell-triggering mechanism by the antibody was carried out. The results revealed that both the IgG fraction and F(ab')2 fragment, but not the monovalent Fab' fragment, demonstrated effective TRF-substituting activity, indicating that cross-linkage or aggregation of the TRF acceptor site(s) may give rise to differentiation signals to the B cells.
建立了一种体外实验系统，以证明在TRF低反应性（DBA2/2Ha×BALB/c）（DC）F雄性小鼠中产生的同种抗血清对TRF高反应性亲代BALB/c B细胞的TRF替代活性。抗血清的TRF替代活性很明显，因为来自TRF高反应性小鼠的经抗Thy-1加C处理、DNP致敏的B细胞受到有效刺激，而来自TRF低反应性DBA/2Ha小鼠的B细胞则未受到刺激，这由二次抗DNP IgG PFC反应的诱导所证明。抗体与TRF高反应性B细胞上存在的一种成分反应的特异性也得到了证实，即抗体活性通过用来自各种TRF高反应性小鼠的B细胞吸收而几乎消除，但不被TRF低反应性DBA/2Ha B细胞吸收所消除。制备了抗血清的IgG组分以及抗体的F(ab')2和Fab'片段，它们在TRF受体位点方面具有可比的反应性，并对抗体触发B细胞的机制进行了分析。结果显示，IgG组分和F(ab')2片段均表现出有效的TRF替代活性，而单价Fab'片段则没有，这表明TRF受体位点的交联或聚集可能会向B细胞发出分化信号。
