Single-domain antibody screening by isPLA-seq

Abstract
Single-domain antibody (sdAb) holds the promising strategies for diverse research and translational applications. Here, we describe a method for the adaptation of the in situ proximity ligation assay (isPLA) followed by sequencing (isPLA-seq) to facilitate screening of a high-sensitive, high-throughput sdAb library for a given protein at subcellular and single-cell resolution. Based on the sequence of complementarity-determining region 3 (CDR3), the recombinant sdAb can be produced for in vitro and in vivo utilities. This method provides a general means to identify the functional measure of sdAb and its complementary epitopes and its potential applications to investigate cellular processes.
Funding Information
  • Ministry of Science and Technology of China (2018YFC1313002)
  • National Natural Science Foundation of China (81825017, 81773034, 81872350, and 8217113342)
  • Tianjin Municipal Science and Technology Commission (18JCZDJC99100)