Centre de Recherche du Service de Santé des Armées, DBAT/Biotechnologies des Anticorps, 24 Avenue des Maquis du Grésivaudan, BP 87, 38702 La Tronche Cedex, France.
J Mol Biol. 2010 Mar 12;396(5):1439-50. doi: 10.1016/j.jmb.2009.12.041. Epub 2010 Jan 4.
Chimeric, humanized and human antibodies have successively been exploited as therapeutics because their increasing human ('self') character is expected to correspond with decreased immunogenicity, which is critical for their clinical development. Thus, humanness has been inferred to predict antibody immunogenicity. Humanness of antibody variable regions (V-regions) has recently been studied using a parameter (here referred to as the H-score) that evaluates similarity to expressed human sequences. Macaque (Macaca fascicularis) antibody sequences are of particular interest because they have been suggested to have extremely human-like character and, recently, macaque single-chain variable fragments with very high affinity for various antigens have been isolated. In this study, the H-scores of all macaque antibody V-regions available in sequence data banks were compared with those of their human counterparts using statistical tests. The results were found to be influenced by the relative size of the human families to which the macaque V-regions are related. As the relevance of families to immunogenicity is suspected but unproven, a new parameter (the 'G-score') was derived from the H-score to avoid this influence, and macaque V-region sequences were reanalyzed using the G-score. Both parameters show that these regions cannot be regarded as human when they derive from heavy chains, but the humanness of light chains is variable. It was shown that 'germline humanization' of a macaque V-region favourably influenced its humanness, as evaluated by both H-score and G-score. In addition, the humanness of macaque sequences presented in patents has been analyzed. The H-score and G-score define objectively the humanness of antibody V-regions, and their use is exemplified here.
嵌合、人源化和人源抗体已相继被开发为治疗药物，因为它们的人源化程度（“自我”特征）增加预计会降低免疫原性，这对其临床开发至关重要。因此，人源化被认为可以预测抗体的免疫原性。抗体可变区 (V 区) 的人源化程度最近使用一种参数（此处称为 H 评分）进行了研究，该参数评估与表达的人类序列的相似性。猕猴 (Macaca fascicularis) 抗体序列特别有趣，因为它们被认为具有极其类似人类的特征，最近还分离出了对各种抗原具有非常高亲和力的猕猴单链可变片段。在这项研究中，使用统计检验比较了所有可在序列数据库中获得的猕猴抗体 V 区的 H 评分与其人类对应物的 H 评分。结果发现，这些结果受到与猕猴 V 区相关的人类家族的相对大小的影响。由于对免疫原性的相关性的怀疑但未经证实，因此从 H 评分推导出了一个新参数（“G 评分”），并使用 G 评分重新分析了猕猴 V 区序列。两个参数都表明，当这些区域来自重链时，不能将其视为人类，但轻链的人源化程度是可变的。研究表明，通过“种系人源化”对猕猴 V 区进行人源化处理，有利于评估其 H 评分和 G 评分。此外，还分析了专利中呈现的猕猴序列的人源化程度。H 评分和 G 评分客观地定义了抗体 V 区的人源化程度，这里举例说明了它们的用途。
