An improved helper phage system for efficient isolation of specific antibody molecules in phage display

On the influence of vector design on antibody phage display

“…Increased host cell stress can make phagemid libraries unstable by providing a growth advantage to clones not encoding a full g3p-fusion protein (Beekwilder et al, 1999). Viral display of antibody fragments can be increased by using g3p-deficient helper phage Rondot et al, 2001;Baek et al, 2002;Soltes et al, 2003) rather than employing the more commonly used g3p-sufficient helper phage. In the absence of helper phage-encoded gene 3, the only source of g3p is the phagemid-encoded g3p fusion protein, which will be efficiently incorporated into virions and displayed.…”

“…In the absence of helper phage-encoded gene 3, the only source of g3p is the phagemid-encoded g3p fusion protein, which will be efficiently incorporated into virions and displayed. However, in some cases g3p-deficient helper phage give decreased production of phagemid virions Baek et al, 2002). A further approach to increasing the display level is lowering the temperature during virion production, however, this can also lead to lower yield of phagemid virions (Chappel et al, 1998).…”

“…These vector combinations include a set of phagemids as well as three different g3p-deficient helper phage, Ex-Phage (Baek et al, 2002), Hyperphage (Rondot et al, 2001) and Phaberge . The results of the study demonstrate that efficient virion production, high viral display level, high infectivity and minimal host cell stress can be obtained simultaneously by carefully selecting phagemid and helper phage types as well as the E. coli host strain.…”

A visible phagemid system for the estimation of Cre-mediated recombination efficiency

“…The g3p protein (calculated as approximately 42 kDa) has been consistently observed in a SDS-PAGE at 60 -65 kDa in earlier reports (Crissman and Smith, 1984;Tesar et al, 1995;Baek et al, 2002). To ensure that scFv with a loxP511 peptide-(Gly 4 Ser 1 ) 1 linker is functional, JM109 cells harboring each vector were grown and IPTG-induced cells were lysed.…”

Ex12 helper phage improves the quality of a phage-displayed antibody library by ameliorating the adverse effect of clonal variations

“…Therefore, it is reasonable to state that the Ex12 helper phage increases the quality of a phage-displayed antibody library by reducing amplification of non-functional phage progenies, thereby facilitating isolation of specific binders from an antibody library. The observation that the E. coli clones carrying pCMTG-L or pCMTG-ΔFab were not able to produce phage progenies using Ex12 helper phage superinfection was expected because of the existence of two amber codons in the gIII of Ex12 helper phage, which prevent the production of a functional wild type pIII in the non-suppressive E. coli TOP10F' strain (20). Notably, the E. coli clone with pCMTG-Fd also did not produce phage progenies, even though the cells expressed the same level of the Fd-ΔpIII fusion as the E. coli clone carrying pCMTG-Fab (data not shown).…”