CDR3 length in antigen-specific immune receptors.
CDR3 length in antigen-specific immune receptors.
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DOI：
10.1084/jem.179.1.323
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发表时间：
1994-01-01
期刊：
影响因子：
--
通讯作者：
Chien YH
中科院分区：
文献类型：
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作者：
Rock EP;Sibbald PR;Davis MM;Chien YH
在免疫球蛋白 (Ig) 和 T 细胞受体 (TCR) 中，淋巴细胞成熟过程中 V、D 和 J 区序列元件的重排在称为互补决定区 3 (CDR3) 环的区域中产生了巨大程度的多样性。所使用的特定 V、D 和 J 元件的变化、精确的重组点以及随机的核苷酸添加都会导致广泛的长度和序列异质性。 CDR3 环通常对于 Igs 中的抗原结合至关重要，并且似乎提供了 TCR 中的主要肽结合残基。为了更好地了解这些序列的物理和选择性限制，我们汇编了 Ig H、L（kappa 和 lambda）以及 TCR alpha、beta、gamma 和 delta 的 CDR3 大小变异信息。 Ig H 和 TCR delta CDR3 的大小变化最大，并且分别比 L 链和 γ 链长得多。相比之下，TCR α 和 β 链分布受到高度限制，平均 CDR3 长度几乎相同，并且它们的长度分布不会因胸腺选择而改变。也许最重要的是，这些 CDR3 长度分布表明，在其推定的配体结合区域中，γ/δ TCR 与 Igs 的相似度高于与 α/β TCR 的相似度，因此γ/δ 和 α/β T 细胞可能具有根本不同的识别特性。
In both immunoglobulins (Ig) and T cell receptors (TCR), the rearrangement of V, D, and J region sequence elements during lymphocyte maturation creates an enormous degree of diversity in an area referred to as the complementarity determining region 3 (CDR3) loop. Variations in the particular V, D, and J elements used, precise points of recombination, and random nucleotide addition all lead to extensive length and sequence heterogeneity. CDR3 loops are often critical for antigen binding in Igs and appear to provide the principal peptide binding residues in TCRs. To better understand the physical and selective constraints on these sequences, we have compiled information on CDR3 size variation for Ig H, L (kappa and lambda) and TCR alpha, beta, gamma, and delta. Ig H and TCR delta CDR3s are the most variable in size and are significantly longer than L and gamma chains, respectively. In contrast, TCR alpha and beta chain distributions are highly constrained, with nearly identical average CDR3 lengths, and their length distributions are not altered by thymic selection. Perhaps most significantly, these CDR3 length profiles suggest that gamma/delta TCRs are more similar to Igs than to alpha/beta TCRs in their putative ligand binding region, and thus gamma/delta and alpha/beta T cells may have fundamentally different recognition properties.