Tagging bloodmeals with phagemids allows feeding of multiple-sample arraysto single cages of mosquitoes (Diptera : Culicidae) and the recovery of single recombinant antibody fragment genes from individual insects

A recombinant single-chain variable-region human antibody fragment (scFv) w as expressed in Escherichia coli, extracted in hypertonic sucrose, mixed di rectly with blood and fed to Anopheles gambiae Giles mosquitoes. When E. co li containing the phagemids that encode these scFv were included in bloodme als, phagemids could be recovered fr om the mosquito midgut for up to 3 d a fter feeding. Furthermore, large an arrays of such gene-tagged scFv-contain ing bloodmeals could be fed to cages of mosquitoes using microtiter plates. Arrays of phagemids with and without an antibody insert were fed to single cages of mosquitoes to test whether individual mosquitoes fed from single wells of such arrays, Phagemids were recovered from 95% of blood-fed female s and >80% of these phagemids were monoclonal. Therefore, it is possible to feed multiple sample arrays of recombinant proteins to single cages of mos quitoes and to recover the genetic material that encodes for only one of th e array elements from individual mosquitoes. This demonstration indicates t hat multiple-sample feeding and recovery strategies are feasible and may re present a viable strategy for future rapid screening of biologically active genes, gene products or microorganisms in live arthropods.