Monoclonal antibodies (mAb) are unique tools in therapeutics and immunodiagnostics applications but many of these applications rely on conjugated mAbs. Whether conjugating drugs or tracers, the conjugation process, frequently taking advantage of primary amines on lysine residues, may affect the binding activity of the antibodies. Furthermore, due to the sticky nature of many mAbs, unfavorable interactions may become eminent, with the result of high background signals. The workload associated with producing mAbs, able to withstand conjugation, preserving stability and affinity and avoiding off-target interactions, is comprehensive and related with only incidental success.

We designed a method, where uncloned hybridomas were pre-selected for secretion of mAbs with the above characteristics. Using human collectin K1 (CL-K1, alias CL-11, Colec11) as a model antigen, mAbs present in culture supernatant from uncloned hybridomas were immobilized on Protein A beads, followed by solid phase biotinylation and subsequent elution. ELISA was employed to compare the binding activity of conjugated vs. unconjugated mAbs, and furthermore for their application in combination with other antibodies. From a group of 96 uncloned hybridomas we accomplished in obtaining five suitable mAbs, among which, two mAbs were superior. The successful conjugation of the selected mAbs with fluorophores and subsequent applications in microscopy and flow cytometry were further demonstrated.

In conclusion, pre-selection of uncloned hybridomas, by testing of their mAbs' ability to withstand conjugation with tracers or drugs, is a successful strategy to avoid a huge workload of cloning numerous hybridomas, in order to obtain conjugatable mAbs.

单克隆抗体（mAb）是治疗和免疫诊断应用程序中的独特工具，但其中许多应用都依赖于缀合的mAb。无论是结合药物还是示踪剂，结合过程（经常利用赖氨酸残基上的伯胺）都可能影响抗体的结合活性。此外，由于许多mAb的粘性，可能会产生不利的相互作用，从而产生高背景信号。与产生单克隆抗体相关的工作负载是全面的，仅能偶然获得成功，能够承受偶联，保持稳定性和亲和力并避免脱靶相互作用。

我们设计了一种方法，其中预选未克隆的杂交瘤以分泌具有上述特征的mAb。使用人类collectin K1（CL-K1，别名CL-11，Colec11）作为模型抗原，将来自未克隆杂交瘤的培养上清液中存在的mAb固定在蛋白A珠上，然后进行固相生物素化并随后洗脱。ELISA被用于比较缀合的mAb与未缀合的mAb的结合活性，并且进一步将它们与其他抗体组合应用。从一组96个未克隆的杂交瘤中，我们获得了五个合适的mAb，其中两个mAb更好。进一步证明了所选单克隆抗体与荧光团的成功偶联以及随后在显微镜和流式细胞术中的应用。

总之，通过测试单克隆抗体承受与示踪剂或药物结合的单克隆抗体的能力，预选未克隆的杂交瘤是避免克隆大量杂交瘤以获得繁琐的单克隆抗体的繁重工作的成功策略。