Editing Phage display (section)

== Applications ==

Applications of phage display technology include determination of interaction partners of a protein (which would be used as the immobilised phage "bait" with a DNA library consisting of all [[coding region|coding sequences]] of a cell, tissue or organism) so that the function or the mechanism of the function of that protein may be determined.<ref>[https://web.archive.org/web/20060628072224/http://genome.wellcome.ac.uk/doc_WTD020763.html Explanation of "Protein interaction mapping" from The Wellcome Trust]</ref> Phage display is also a widely used method for ''in vitro'' protein evolution (also called [[protein engineering]]). As such, phage display is a useful tool in [[drug discovery]]. It is used for finding new [[ligand]]s (enzyme inhibitors, receptor agonists and antagonists) to target proteins.<ref name="pmid16258189">{{cite journal |vauthors=Lunder M, Bratkovic T, Doljak B, Kreft S, Urleb U, Strukelj B, Plazar N | title = Comparison of bacterial and phage display peptide libraries in search of target-binding motif | journal = Appl. Biochem. Biotechnol. | volume = 127 | issue = 2 | pages = 125–31 |date=November 2005 | pmid = 16258189 | doi = 10.1385/ABAB:127:2:125 | s2cid = 45243314 }}</ref><ref name="pmid15913550">{{cite journal |vauthors=Bratkovic T, Lunder M, Popovic T, Kreft S, Turk B, Strukelj B, Urleb U | title = Affinity selection to papain yields potent peptide inhibitors of cathepsins L, B, H, and K | journal = Biochem. Biophys. Res. Commun. | volume = 332 | issue = 3 | pages = 897–903 |date=July 2005 | pmid = 15913550 | doi = 10.1016/j.bbrc.2005.05.028 }}</ref><ref name="pmid15863836">{{cite journal |vauthors=Lunder M, Bratkovic T, Kreft S, Strukelj B | title = Peptide inhibitor of pancreatic lipase selected by phage display using different elution strategies | journal = J. Lipid Res. | volume = 46 | issue = 7 | pages = 1512–6 |date=July 2005 | pmid = 15863836 | doi = 10.1194/jlr.M500048-JLR200  | doi-access = free }}</ref> The technique is also used to determine [[Tumor antigen|tumour antigens]] (for use in diagnosis and therapeutic targeting)<ref name="Hufton_1999">{{cite journal |vauthors=Hufton SE, Moerkerk PT, Meulemans EV, de Bruïne A, Arends JW, Hoogenboom HR | title = Phage display of cDNA repertoires: the pVI display system and its applications for the selection of immunogenic ligands | journal = J. Immunol. Methods | volume = 231 | issue = 1–2 | pages = 39–51 |date=December 1999 | pmid = 10648926 | doi = 10.1016/S0022-1759(99)00139-8 }}</ref> and in searching for [[protein-DNA interaction]]s<ref name="Gommans_2005">{{cite journal |vauthors=Gommans WM, Haisma HJ, Rots MG | title = Engineering zinc finger protein transcription factors: the therapeutic relevance of switching endogenous gene expression on or off at command | journal = J. Mol. Biol. | volume = 354 | issue = 3 | pages = 507–19 |date=December 2005 | pmid = 16253273 | doi = 10.1016/j.jmb.2005.06.082 }}</ref> using specially-constructed DNA libraries with randomised segments. Recently, phage display has also been used in the context of cancer treatments - such as the adoptive cell transfer approach.<ref name=":0">{{cite web|title=CAR T Cells: Engineering Patients' Immune Cells to Treat Their Cancers|url=https://www.cancer.gov/about-cancer/treatment/research/car-t-cells|website=National Cancer Institute|access-date=9 February 2018|date=2013-12-06}}</ref> In these cases, phage display is used to create and select synthetic antibodies that target tumour surface proteins.<ref name=":0" /> These are made into synthetic receptors for T-Cells collected from the patient that are used to combat the disease.<ref>{{cite journal | vauthors = Løset GÅ, Berntzen G, Frigstad T, Pollmann S, Gunnarsen KS, Sandlie I | title = Phage Display Engineered T Cell Receptors as Tools for the Study of Tumor Peptide-MHC Interactions | journal = Frontiers in Oncology | volume = 4 | issue = 378 | pages = 378 | date = 12 January 2015 | pmid = 25629004 | pmc = 4290511 | doi = 10.3389/fonc.2014.00378 | doi-access = free }}</ref>

Competing methods for [[directed evolution|''in vitro'' protein evolution]] include [[yeast display]], [[bacterial display]], [[ribosome display]], and [[mRNA display]].{{cn|date=October 2022}}

=== Antibody maturation ''in vitro'' ===
The invention of [[antibody]] phage display revolutionised antibody drug discovery. Initial work was done by laboratories at the [[MRC Laboratory of Molecular Biology]] ([[Greg Winter]] and [[John McCafferty]]), the [[Scripps Research Institute]] (Richard Lerner and Carlos F. Barbas) and the [[German Cancer Research Centre]] (Frank Breitling and Stefan Dübel).<ref name="pmid2247164">{{cite journal | vauthors = McCafferty J, Griffiths AD, Winter G, Chiswell DJ | title = Phage antibodies: filamentous phage displaying antibody variable domains | journal = Nature | volume = 348 | issue = 6301 | pages = 552–4 | date = December 1990 | pmid = 2247164 | doi = 10.1038/348552a0 | bibcode = 1990Natur.348..552M | s2cid = 4258014 | author-link4 = David Chiswell | author-link1 = John McCafferty | author-link3 = Greg Winter }}</ref><ref name="isbn0-87969-740-7">{{cite book | vauthors = Scott JS, ((Barbas CF III)), Burton DA | title = Phage Display: A Laboratory Manual | publisher = Cold Spring Harbor Laboratory Press | location = Plainview, N.Y | year = 2001 | isbn = 978-0-87969-740-2 }}</ref><ref>{{cite journal | vauthors = Breitling F, Dübel S, Seehaus T, Klewinghaus I, Little M | title = A surface expression vector for antibody screening | journal = Gene | volume = 104 | issue = 2 | pages = 147–53 | date = August 1991 | pmid = 1916287 | doi = 10.1016/0378-1119(91)90244-6 }}</ref> In 1991, The Scripps group reported the first display and selection of human antibodies on phage.<ref name="pmid1896445">{{cite journal | vauthors = Barbas CF, Kang AS, Lerner RA, Benkovic SJ | title = Assembly of combinatorial antibody libraries on phage surfaces: the gene III site | journal = Proceedings of the National Academy of Sciences of the United States of America | volume = 88 | issue = 18 | pages = 7978–82 | date = September 1991 | pmid = 1896445 | pmc = 52428 | doi = 10.1073/pnas.88.18.7978 | bibcode = 1991PNAS...88.7978B | doi-access = free }}</ref> This initial study described the rapid isolation of human antibody [[Fragment antigen-binding|Fab]] that bound [[tetanus toxin]] and the method was then extended to rapidly clone human anti-HIV-1 antibodies for vaccine design and therapy.<ref name="pmid1719545">{{cite journal | vauthors = Burton DR, Barbas CF, Persson MA, Koenig S, Chanock RM, Lerner RA | title = A large array of human monoclonal antibodies to type 1 human immunodeficiency virus from combinatorial libraries of asymptomatic seropositive individuals | journal = Proceedings of the National Academy of Sciences of the United States of America | volume = 88 | issue = 22 | pages = 10134–7 | date = November 1991 | pmid = 1719545 | pmc = 52882 | doi = 10.1073/pnas.88.22.10134 | bibcode = 1991PNAS...8810134B | doi-access = free }}</ref><ref name="pmid1384050">{{cite journal | vauthors = Barbas CF, Björling E, Chiodi F, Dunlop N, Cababa D, Jones TM, Zebedee SL, Persson MA, Nara PL, Norrby E | title = Recombinant human Fab fragments neutralize human type 1 immunodeficiency virus in vitro | journal = Proceedings of the National Academy of Sciences of the United States of America | volume = 89 | issue = 19 | pages = 9339–43 | date = October 1992 | pmid = 1384050 | pmc = 50122 | doi = 10.1073/pnas.89.19.9339 | bibcode = 1992PNAS...89.9339B | doi-access = free }}</ref><ref name="pmid7973652">{{cite journal | vauthors = Burton DR, Pyati J, Koduri R, Sharp SJ, Thornton GB, Parren PW, Sawyer LS, Hendry RM, Dunlop N, Nara PL | title = Efficient neutralization of primary isolates of HIV-1 by a recombinant human monoclonal antibody | journal = Science | volume = 266 | issue = 5187 | pages = 1024–7 | date = November 1994 | pmid = 7973652 | doi = 10.1126/science.7973652 | bibcode = 1994Sci...266.1024B }}</ref><ref name="pmid7490758">{{cite journal | vauthors = Yang WP, Green K, Pinz-Sweeney S, Briones AT, Burton DR, Barbas CF | title = CDR walking mutagenesis for the affinity maturation of a potent human anti-HIV-1 antibody into the picomolar range | journal = Journal of Molecular Biology | volume = 254 | issue = 3 | pages = 392–403 | date = December 1995 | pmid = 7490758 | doi = 10.1006/jmbi.1995.0626 }}</ref><ref name="pmid8170992">{{cite journal | vauthors = Barbas CF, Hu D, Dunlop N, Sawyer L, Cababa D, Hendry RM, Nara PL, Burton DR | title = In vitro evolution of a neutralizing human antibody to human immunodeficiency virus type 1 to enhance affinity and broaden strain cross-reactivity | journal = Proceedings of the National Academy of Sciences of the United States of America | volume = 91 | issue = 9 | pages = 3809–13 | date = April 1994 | pmid = 8170992 | pmc = 43671 | doi = 10.1073/pnas.91.9.3809 | bibcode = 1994PNAS...91.3809B | doi-access = free }}</ref>

Phage display of antibody libraries has become a powerful method for both studying the immune response as well as a method to rapidly select and evolve human antibodies for therapy. Antibody phage display was later used by Carlos F. Barbas at The Scripps Research Institute to create synthetic human antibody libraries, a principle first patented in 1990 by Breitling and coworkers (Patent CA 2035384), thereby allowing human antibodies to be created in vitro from synthetic diversity elements.<ref name="pmid1584777">{{cite journal |vauthors=Barbas CF, Bain JD, Hoekstra DM, Lerner RA | title = Semisynthetic combinatorial antibody libraries: a chemical solution to the diversity problem | journal = Proc. Natl. Acad. Sci. U.S.A. | volume = 89 | issue = 10 | pages = 4457–61 |date=May 1992 | pmid = 1584777 | pmc = 49101 | doi =10.1073/pnas.89.10.4457 | bibcode = 1992PNAS...89.4457B | doi-access = free }}</ref><ref name="pmid7694276">{{cite journal |vauthors=Barbas CF, Languino LR, Smith JW | title = High-affinity self-reactive human antibodies by design and selection: targeting the integrin ligand binding site | journal = Proc. Natl. Acad. Sci. U.S.A. | volume = 90 | issue = 21 | pages = 10003–7 |date=November 1993 | pmid = 7694276 | pmc = 47701 | doi = 10.1073/pnas.90.21.10003 |bibcode = 1993PNAS...9010003B | doi-access = free }}</ref><ref name=Barbas_1995>{{cite journal |vauthors=Barbas CF, Wagner J | title = Synthetic Human Antibodies: Selecting and Evolving Functional Proteins | journal = Methods |date=October 1995 | volume = 8 | issue = 2 | pages = 94–103|doi=10.1006/meth.1995.9997}}</ref><ref name="pmid7585190">{{cite journal | author = Barbas CF | title = Synthetic human antibodies | journal = Nat. Med. | volume = 1 | issue = 8 | pages = 837–9 |date=August 1995 | pmid = 7585190 | doi = 10.1038/nm0895-837 | s2cid = 6983649 }}</ref>

Antibody libraries displaying millions of different antibodies on phage are often used in the pharmaceutical industry to isolate highly specific therapeutic antibody leads, for development into antibody drugs primarily as anti-cancer or anti-inflammatory therapeutics. One of the most successful was [[adalimumab]], discovered by [[Cambridge Antibody Technology]] as D2E7 and developed and marketed by [[Abbott Laboratories]]. Adalimumab, an antibody to [[TNF alpha]], was the world's first fully human antibody<ref name="pmid17420735">{{cite journal | author = Lawrence S | title = Billion dollar babies--biotech drugs as blockbusters | journal = Nat. Biotechnol. | volume = 25 | issue = 4 | pages = 380–2 |date=April 2007 | pmid = 17420735 | doi = 10.1038/nbt0407-380 | s2cid = 205266758 }}</ref> to achieve annual sales exceeding $1bn.<ref>[https://web.archive.org/web/20110717145527/http://telegraph.uk-wire.com/cgi-bin/articles/200601251501444434X.html Cambridge Antibody: Sales update | Company Announcements | Telegraph<!-- Bot generated title -->]</ref>