title: Single domain antibodies: promising experimental and therapeutic tools in infection and immunity.
abstract: Antibodies are important tools for experimental research and medical applications. Most antibodies are composed of two heavy and two light chains. Both chains contribute to the antigen-binding site which is usually flat or concave. In addition to these conventional antibodies, llamas, other camelids, and sharks also produce antibodies composed only of heavy chains. The antigen-binding site of these unusual heavy chain antibodies (hcAbs) is formed only by a single domain, designated VHH in camelid hcAbs and VNAR in shark hcAbs. VHH and VNAR are easily produced as recombinant proteins, designated single domain antibodies (sdAbs) or nanobodies. The CDR3 region of these sdAbs possesses the extraordinary capacity to form long fingerlike extensions that can extend into cavities on antigens, e.g., the active site crevice of enzymes. Other advantageous features of nanobodies include their small size, high solubility, thermal stability, refolding capacity, and good tissue penetration in vivo. Here we review the results of several recent proof-of-principle studies that open the exciting perspective of using sdAbs for modulating immune functions and for targeting toxins and microbes.
authors.affiliation: Institute of Immunology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
authors.forename: Janusz
authors.initials: J
authors.lastname: Wesolowski
authors.forename: Vanina
authors.initials: V
authors.lastname: Alzogaray
authors.forename: Jan
authors.initials: J
authors.lastname: Reyelt
authors.forename: Mandy
authors.initials: M
authors.lastname: Unger
authors.forename: Karla
authors.initials: K
authors.lastname: Juarez
authors.forename: Mariela
authors.initials: M
authors.lastname: Urrutia
authors.forename: Ana
authors.initials: A
authors.lastname: Cauerhff
authors.forename: Welbeck
authors.initials: W
authors.lastname: Danquah
authors.forename: Björn
authors.initials: B
authors.lastname: Rissiek
authors.forename: Felix
authors.initials: F
authors.lastname: Scheuplein
authors.forename: Nicole
authors.initials: N
authors.lastname: Schwarz
authors.forename: Sahil
authors.initials: S
authors.lastname: Adriouch
authors.forename: Olivier
authors.initials: O
authors.lastname: Boyer
authors.forename: Michel
authors.initials: M
authors.lastname: Seman
authors.forename: Alexei
authors.initials: A
authors.lastname: Licea
authors.forename: David V
authors.initials: DV
authors.lastname: Serreze
authors.forename: Fernando A
authors.initials: FA
authors.lastname: Goldbaum
authors.forename: Friedrich
authors.initials: F
authors.lastname: Haag
authors.forename: Friedrich
authors.initials: F
authors.lastname: Koch-Nolte
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000906:Antibodies / Q000737:chemistry* / Q000276:immunology; D002161:Camelids, New World / Q000276:immunology; D022801:Complementarity Determining Regions / Q000737:chemistry / Q000276:immunology; D007143:Immunoglobulin Heavy Chains / Q000737:chemistry* / Q000276:immunology; D008968:Molecular Conformation; D008969:Molecular Sequence Data; D011994:Recombinant Proteins / Q000737:chemistry / Q000276:immunology; D016415:Sequence Alignment; D012754:Sharks / Q000276:immunology
chemical_list: D000906:Antibodies; D022801:Complementarity Determining Regions; D007143:Immunoglobulin Heavy Chains; D011994:Recombinant Proteins