Leukocyte Adhesion Laboratory, Cancer Research UK London Research Institute, London, England.
Dev Dyn. 2011 Sep;240(9):2194-203. doi: 10.1002/dvdy.22709.
S100a8 is a cytosolic protein expressed in myeloid cells where it forms a stable heterodimer with another S100 protein family member, S100a9. The S100a9(-/-) mouse is viable and phenotypically normal, whereas the S100a8(-/-) condition is embryonic lethal. We present evidence that S100a8, without S100a9, has a previously unrecognized role in embryo development between fertilization and the 8-cell stage at embryonic day (E) 2.5. S100a8 also has a second role in the maternal deciduum, where expression is associated with the vasculature from the E8.5 stage to the formation of mature placenta. Uterine natural killer cells that have a role in vascular remodelling colocalise with the S100a8 vascular expression in the metrial triangle. In inflammatory responses in peripheral tissues, S100a8 is a potent chemoattractant and also an anti-oxidant. Both roles may be important in the developing placenta. Thus we highlight two new S100a9-independent roles for S100a8 in early embryo development.
S100a8 是一种胞质蛋白，在髓系细胞中表达，在那里它与另一种 S100 蛋白家族成员 S100a9 形成稳定的异二聚体。S100a9(-/-) 小鼠是可行的，表型正常，而 S100a8(-/-) 条件是胚胎致死。我们提供的证据表明，S100a8 在受精后至胚胎第 2.5 天的 8 细胞阶段之间的胚胎发育中具有以前未被认识到的作用，而没有 S100a9。S100a8 在母体蜕膜中也有第二个作用，其表达与从 E8.5 阶段到成熟胎盘形成的血管有关。在血管重塑中起作用的子宫自然杀伤细胞与蜕膜三角中的 S100a8 血管表达共定位。在周围组织的炎症反应中，S100a8 是一种有效的趋化因子，也是一种抗氧化剂。这两个作用在发育中的胎盘可能都很重要。因此，我们强调了 S100a8 在早期胚胎发育中的两个新的 S100a9 非依赖性作用。
