背景:粘蛋白16(MUC16)过表达与癌症进展有关,转移,高级别浆液性卵巢癌和其他恶性肿瘤的治疗耐药性。MUC16的裂解形成独立的双峰片段,shed串联重复序列作为携带卵巢癌生物标志物(CA125)的蛋白质和在MUC16致癌行为中至关重要的近端膜结合成分循环。一个人性化的,靶向近端胞外域的高亲和力抗体代表了针对MUC16的潜在治疗剂,具有较低的抗原潜力和受限的人组织表达.
结果:这里,我们证明了人源化抗体作为单克隆抗体的潜在治疗多功能性,抗体药物偶联物,和嵌合抗原受体。我们报道了4H11-scFv的晶体结构,源自特异性靶向MUC16C末端区域的抗体,单独使用,并具有26个氨基酸的MUC16片段,分辨率为2.36和2.47,分别。scFv与由两个连续的β-转角和由2个氢键稳定的β-发夹组成的表位形成稳健的相互作用。4H11-scFv内的VH-VL界面通过11个氢键和阳离子-π相互作用的复杂网络稳定。
结论:一起,我们的研究提供了对抗体-MUC16胞外域相互作用的深入了解,并提高了我们设计治疗特性可能优于抗CA125部分抗体的药物的能力.
BACKGROUND: Mucin 16 (MUC16) overexpression is linked with cancer progression, metastasis, and therapy resistance in high grade serous ovarian cancer and other malignancies. The cleavage of MUC16 forms independent bimodular fragments, the shed tandem repeat sequence which circulates as a protein bearing the ovarian cancer biomarker (CA125) and a proximal membrane-bound component which is critical in MUC16 oncogenic behavior. A humanized, high affinity antibody targeting the proximal ectodomain represents a potential therapeutic agent against MUC16 with lower antigenic potential and restricted human tissue expression.
RESULTS: Here, we demonstrate the potential therapeutic versatility of the humanized antibody as a monoclonal antibody, antibody drug conjugate, and chimeric antigen receptor. We report the crystal structures of 4H11-scFv, derived from an antibody specifically targeting the MUC16 C-terminal region, alone and in complex with a 26-amino acid MUC16 segment resolved at 2.36 Å and 2.47 Å resolution, respectively. The scFv forms a robust interaction with an epitope consisting of two consecutive β-turns and a β-hairpin stabilized by 2 hydrogen bonds. The VH-VL interface within the 4H11-scFv is stabilized through an intricate network of 11 hydrogen bonds and a cation-π interaction.
CONCLUSIONS: Together, our studies offer insight into antibody-MUC16 ectodomain interaction and advance our ability to design agents with potentially improved therapeutic properties over anti-CA125 moiety antibodies.