Kenny J J, Stall A M, Sieckmann D G, Lamers M C, Finkelman F D, Finch L, Longo D L
Program Resources Inc./DynCorp. NCI-FCRDC, Frederick, MD 21702-1201.
J Immunol. 1991 Apr 15;146(8):2568-77.
The combined expression of the M167 mu/kappa anstiphosphocholine (PC) transgenes with the x-linked immunodeficiency gene, xid, results in an almost total failure to develop B cells in the peripheral lymphoid organs of such mice. Although there is no significant difference between the normal transgene positive (TG+) female offspring and the immunodeficient TG+ xid males with respect to the number of B220+ pre-B cells and IgM+B220+B cells that develop in their bone marrow, the hemizygous xid males have 85% fewer B cells in their spleens than the phenotypically normal heterozygous F1 females. In xid M167-mu-transgenic mice, PC-specific B cells also fail to develop in the spleen; however, numerous B cells bearing the mua+VH1(+)-transgene product associated with endogenous kappa L chains that do not give rise PC-specific antibodies are present. In the phenotypically normal TG+ (B6.CBA/N x mu 243-4)F1 female mice, PC-specific B cells represent almost 10% of the total B cell population, and these B cells express an M167-Id that has been produced by association of the VH1 transgene product with an endogenous V kappa 24L chain. B cells expressing the normally dominant T15-Id are not detectable in the spleens of these M167 mu-transgenic mice. Furthermore, M167-Id+ B cells are present at a fivefold lower level in the bone marrow of mu-TG+ normal mice than in their spleens. These data suggest that the PC-specific B cells that develop in TG+ xid mice are either clonally deleted via some "IgR-directed" mechanism or they fail to receive the appropriate signals to exit the bone marrow or to enter the peripheral lymphoid tissues. This hypothesis is supported by the finding that TNP-specific B cells develop normally and do not undergo clonal deletion in xid mice carrying the Sp6 mu/kappa anti-TNP transgenes.
M167 鼠/κ抗磷酸胆碱(PC)转基因与 X 连锁免疫缺陷基因 xid 联合表达,导致此类小鼠外周淋巴器官中 B 细胞几乎完全无法发育。尽管正常转基因阳性(TG+)雌性后代与免疫缺陷的 TG+ xid 雄性小鼠在骨髓中发育的 B220+前 B 细胞和 IgM+B220+B 细胞数量方面没有显著差异,但半合子 xid 雄性小鼠脾脏中的 B 细胞比表型正常的杂合 F1 雌性小鼠少 85%。在 xid M167-μ转基因小鼠中,PC 特异性 B 细胞在脾脏中也无法发育;然而,存在许多携带与内源性κ轻链相关的 mua+VH1(+)-转基因产物的 B 细胞,这些 B 细胞不会产生 PC 特异性抗体。在表型正常的 TG+(B6.CBA/N×μ243-4)F1 雌性小鼠中,PC 特异性 B 细胞占总 B 细胞群体的近 10%,并且这些 B 细胞表达一种由 VH1 转基因产物与内源性 Vκ24L 链结合产生的 M167-Id。在这些 M167 μ转基因小鼠的脾脏中检测不到表达正常占主导地位的 T15-Id 的 B 细胞。此外,M167-Id+B 细胞在 μ-TG+正常小鼠骨髓中的水平比在其脾脏中低五倍。这些数据表明,在 TG+ xid 小鼠中发育的 PC 特异性 B 细胞要么通过某种“IgR 导向”机制发生克隆性缺失,要么它们未能接收到离开骨髓或进入外周淋巴组织的适当信号。这一假设得到了以下发现的支持:在携带 Sp6 μ/κ抗 TNP 转基因的 xid 小鼠中,TNP 特异性 B 细胞正常发育且不发生克隆性缺失。