VHH antibodies: emerging reagents for the analysis of environmental chemicals

Abstract

A VHH antibody (or nanobody) is the antigen binding fragment of heavy chain only antibodies. Discovered nearly 25 years ago, they have been investigated for their use in clinical therapeutics and immunodiagnostics, and more recently for environmental monitoring applications. A new and valuable immunoreagent for the analysis of small molecular weight environmental chemicals, VHH will overcome many pitfalls encountered with conventional reagents. In the work so far, VHH antibodies often perform comparably to conventional antibodies for small molecule analysis, are amenable to numerous genetic engineering techniques, and show ease of adaption to other immunodiagnostic platforms for use in environmental monitoring. Recent reviews cover the structure and production of VHH antibodies as well as their use in clinical settings. However, no report focuses on the use of these VHH antibodies to small environmental chemicals (MW <1,500 Da). This review article summarizes the efforts made to produce VHHs to various environmental targets, compares the VHH-based assays with conventional antibody assays, and discusses the advantages and limitations in developing these new antibody reagents particularly to small molecule targets.

Deiminated proteins in extracellular vesicles and serum of llama (Lama glama)—Novel insights into camelid immunity

“…These types of homodimeric, light chain-less antibodies have evolved through convergent evolution (Brooks et al, 2018), in at least two groups (camelids and cartilaginous fish), and their variable binding domains (V H H S ) are of great value for therapeutic and diagnostic applications (Muyldermans, 2013;Criscitiello, 2014;Steeland et al, 2016;Könning et al, 2017;Henry et al, 2019). Nanobodies can act against challenging targets such as small molecules and toxins (Wesolowski et al, 2009;Bever et al, 2016), viruses (Wei et al, 2011;Hassiki et al, 2016;Vanlandschoot et al, 2011;Cohen, 2018), enzymes (Muyldermans, 2013), ion channels (Wei et al, 2011;Danquah et al, 2016) and G protein-coupled receptors GPCRs (Cromie et al, 2015). Llama nanobodies have been shown to tether to early endosomes and to mitochondria (Traub, 2019), be used for diagnostics (Shriver-Lake et al, 2018), be used for design of cancer immunotherapeutics (Hussack et al, 2018;Bannas and Koch-Nolte, 2018;Rossotti et al, 2019) and have been approved for passive immunotherapy (Sheridan, 2019).…”

Large Diversity of Functional Nanobodies from a Camelid Immune Library Revealed by an Alternative Analysis of Next-Generation Sequencing Data

“…This limited sample represents an interesting mix of ligand-dependent and -independent modes-of-action for the blocking of RON signaling. Many examples document the ability of the outbred camelid’s immune response to generate nanobodies against challenging targets including ion channels (29–31), GPCRs (32, 33), small molecules and toxins (34, 35), viruses (34, 36) and enzymes (2). To our knowledge, this is the first example to illustrate the potential extent of an outbred camelid’s functional immune response in terms of sequence diversity.…”

Antigen recognition by single-domain antibodies: structural latitudes and constraints

“…Multiple studies have reported the isolation of hapten-specific V H Hs without investigating their structures, 119 although several also reported weaker and inconsistent serum heavy chain-only IgG titers compared with conventional IgG titers against the hapten. No studies have reported hapten-specific V NAR s, and only one study has described a carbohydrate-specific V H H directed against Neisseira meningitidis lipopolysaccharide; 120 at least two camelid V H Hs have been described that bind to glycopeptide epitopes.…”