免疫球蛋白(Ig)已被广泛认为仅由B谱系细胞产生。然而,越来越多的证据表明Ig在一系列癌细胞中的表达,以及包括上皮细胞在内的正常细胞,表皮细胞,系膜细胞,单核细胞,和中性粒细胞。甚至已经发现Ig在非B细胞中在免疫特权位点如神经元和生精细胞中表达。尽管这些非B细胞衍生的Ig(非B-Ig)与常规Ig(B-Ig)共享相同的对称结构,进一步的研究揭示了非B-Ig的独特特征,如限制性可变区和异常糖基化。此外,非B-Ig表现出促进癌细胞恶性行为的特性,因此,它可以在临床上用作潜在的治疗生物标志物或靶标。非B-Ig的产生和调节的阐明肯定会扩大我们对免疫学的理解。
Immunoglobulin (Ig) has been widely acknowledged to be produced solely by B-lineage cells. However, growing evidence has demonstrated the expression of Ig in an array of cancer cells, as well as normal cells including epithelial cells, epidermal cells, mesangial cells, monocytes, and neutrophils. Ig has even been found to be expressed in non-B cells at immune-privileged sites such as neurons and spermatogenic cells. Despite these non-B cell-derived Igs (non-B-Igs) sharing the same symmetric structures with conventional Igs (B-Igs), further studies have revealed unique characteristics of non-B-Ig, such as restricted variable region and aberrant glycosylation. Moreover, non-B-Ig exhibits properties of promoting malignant behaviours of cancer cells, therefore it could be utilised in the clinic as a potential therapeutic biomarker or target. The elucidation of the generation and regulation of non-B-Ig will certainly broaden our understanding of immunology.