Davis Randall S
Division of Developmental and Clinical Immunology, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama 35294-3300, USA.
Annu Rev Immunol. 2007;25:525-60. doi: 10.1146/annurev.immunol.25.022106.141541.
Discovery of a large family of Fc receptor-like (FCRL) molecules, homologous to the well-known receptors for the Fc portion of immunoglobulin (FCR), has uncovered an impressive abundance of immunoglobulin superfamily (IgSF) genes in the human 1q21-23 chromosomal region and revealed significant diversity for these genes between humans and mice. The observation that FCRL representatives are members of an ancient multigene family that share a common ancestor with the classical FCR is underscored by their linked genomic locations, gene structure, shared extracellular domain composition, and utilization of common cytoplasmic tyrosine-based signaling elements. In contrast to the conventional FCR, however, FCRL molecules possess diverse extracellular frameworks, autonomous or dual signaling properties, and preferential B lineage expression. Most importantly, there is no strong evidence thus far to support a role for them as Ig-binding receptors. These characteristics, in addition to their identification in malignancies and autoimmune disorders, predict a fundamental role for these receptors as immunomodulatory agents in normal and subverted B lineage cells.
发现了一大类与免疫球蛋白（Ig）Fc部分的知名受体同源的Fc受体样（FCRL）分子，这揭示了人类1q21 - 23染色体区域中免疫球蛋白超家族（IgSF）基因数量惊人，并且显示出这些基因在人类和小鼠之间存在显著差异。FCRL代表分子是一个古老多基因家族的成员，与经典FCR有共同祖先，这一观点得到了它们相连的基因组位置、基因结构、共享的细胞外结构域组成以及对基于酪氨酸的共同细胞质信号元件的利用的支持。然而，与传统FCR不同，FCRL分子具有多样的细胞外框架、自主或双重信号特性以及优先的B细胞系表达。最重要的是，迄今为止没有强有力的证据支持它们作为Ig结合受体的作用。这些特征，再加上它们在恶性肿瘤和自身免疫性疾病中的发现，预示着这些受体在正常和异常的B细胞系细胞中作为免疫调节因子发挥着重要作用。
