B細(xì)胞發(fā)育和抗體多樣性研究模型B6-Igl KO小鼠的介紹

圖2 免疫球蛋白（Ig）重鏈和輕鏈基因座重排產(chǎn)生不同抗原特異性的抗體和BCR^[7]

λ輕鏈與B細(xì)胞發(fā)育及疾病關(guān)聯(lián)
B細(xì)胞在發(fā)育過程中通過基因重排生成功能性B細(xì)胞受體（BCR）。B細(xì)胞優(yōu)先重排κ輕鏈基因，而λ輕鏈（Igλ）主要作為κ輕鏈（Igκ）的替代，確保即使Igκ重排失敗，B細(xì)胞仍能產(chǎn)生功能性抗體，這對維持抗體庫的多樣性和功能性至關(guān)重要^[8-10]。Igλ作為BCR的一部分，能夠結(jié)合特定抗原，促進(jìn)B細(xì)胞激活及其分化為漿細(xì)胞和記憶B細(xì)胞。Igλ的異常重排或功能失調(diào)可能導(dǎo)致自身免疫疾病，如系統(tǒng)性紅斑狼瘡（SLE）和類風(fēng)濕性關(guān)節(jié)炎，同時也與多發(fā)性骨髓瘤、輕鏈淀粉樣變性（AL淀粉樣變性）等B細(xì)胞惡性腫瘤相關(guān)^[11-13]。此外，Igλ鏈的缺失或異常與低丙種球蛋白血癥、普通變異型免疫缺陷病（CVID）以及原發(fā)性免疫缺陷�。≒IDD）等疾病相關(guān)，表現(xiàn)為免疫球蛋白水平低下和感染易感性增加^[14-16]。
 

圖5 野生型和B6-Igl KO小鼠脾臟和骨髓中表達(dá)免疫球蛋白λ輕鏈（Igλ）或κ輕鏈（Igκ）的B細(xì)胞比例

總  結(jié)
由于λ輕鏈基因座（Igl）的敲除，B6-Igl KO小鼠（產(chǎn)品編號：C001550）體內(nèi)B細(xì)胞僅表達(dá)κ輕鏈免疫球蛋白。因此，B6-Igl KO小鼠可用于研究B細(xì)胞發(fā)育和功能過程中λ輕鏈的作用，制備僅含κ輕鏈的小鼠抗體，分析λ輕鏈在特定免疫反應(yīng)或自身免疫性疾病中的機(jī)制。此模型還可用于探索抗體多樣性、免疫系統(tǒng)調(diào)節(jié)機(jī)制及潛在治療方法。同時，可與人源化的輕鏈小鼠模型配種，構(gòu)建表達(dá)特定輕鏈的人源抗體鼠，用于制備全人源共輕鏈抗體，或在小鼠抗體序列缺失情況下插入其他類型或物種的抗體序列進(jìn)行體內(nèi)研究。

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