Cudkowicz G, Shearer G M, Ito T
J Exp Med. 1970 Oct 1;132(4):623-35. doi: 10.1084/jem.132.4.623.
Marrow cells and 5 x 10(7) thymocytes of unprimed (C57BL/6 x DBA/2)F(1), (C57BL/10 x WB)F(1) and (C3H x C57BL)F(1) donor mice were mixed in vitro and transplanted into X-irradiated syngeneic hosts. Upon injection of sheep erythrocytes, splenic plaque-forming cells (PFC) secreting IgM (direct PFC or IgG (indirect PFC) hemolytic antibody were enumerated at the time of peak responses. By grading the numbers of marrow cells, inocula were found that contained few immunocompetent cells reaching the recipient spleens, interacting with thymocytes or other accessory cells (or both), and generating PFC. The frequency of responses in BDF(1) mice conformed to Poisson statistics, indicating that immunocompetent marrow cells participated in a single-hit interaction limiting PFC responses. The marrow cells assayed were not restricted for the antibody class (IgM versus IgG) to be secreted by mature PFC. Unrestricted marrow cells could have been either the precursors of PFC or accessory cells. Different results were obtained in BWF(1) and C3BF(1) mice. The frequency of responses in relation to the number of marrow cells grafted did not follow Poisson statistics, and the limiting cells were restricted for antibody class. Presumably, immunocompetent cells of these strains were more heterogeneous than those of BDF(1) mice and participated in a multiplicity of cell-to-cell interactions. The strain differences reflected inherent properties of marrow cells and not influences of the environment in which PFC were produced. The results confirmed for bone marrow the heterogeneity of immunocompetent cells reported by others for spleen, and suggested that genetic factors such as "immune response" genes regulate cellular differentiation also for functions other than those related to antibody specificity.
将未致敏的(C57BL/6×DBA/2)F₁、(C57BL/10×WB)F₁和(C3H×C57BL)F₁供体小鼠的骨髓细胞和5×10⁷个胸腺细胞在体外混合,然后移植到经X射线照射的同基因宿主中。注射绵羊红细胞后,在反应高峰期计数分泌IgM(直接空斑形成细胞或IgG(间接空斑形成细胞)溶血抗体的脾空斑形成细胞(PFC)。通过对骨髓细胞数量进行分级,发现接种物中含有很少的免疫活性细胞,这些细胞到达受体脾脏,与胸腺细胞或其他辅助细胞(或两者)相互作用,并产生PFC。BDF₁小鼠的反应频率符合泊松统计,表明免疫活性骨髓细胞参与了限制PFC反应的单次相互作用。所检测的骨髓细胞对于成熟PFC分泌的抗体类别(IgM对IgG)没有限制。不受限制的骨髓细胞可能是PFC的前体或辅助细胞。在BWF₁和C3BF₁小鼠中得到了不同的结果。与移植的骨髓细胞数量相关的反应频率不遵循泊松统计,并且限制细胞对于抗体类别是受限的。据推测,这些品系的免疫活性细胞比BDF₁小鼠的更具异质性,并参与了多种细胞间相互作用。品系差异反映了骨髓细胞的固有特性,而非产生PFC的环境的影响。这些结果证实了其他人报道的骨髓免疫活性细胞的异质性,并表明诸如“免疫反应”基因等遗传因素也调节与抗体特异性无关的其他功能的细胞分化。