INVESTIGADORES
URRUTIA Mariela
congresos y reuniones científicas
Título:
Development of a quantitative immunoassay for gluten-free food analysis based on a new antigen-binding
Autor/es:
DOÑA V, URRUTIA M, BAYARDO M, GOLDBAUM F, CHIRDOF
Lugar:
Verlag Wissenschaftliche Scripten, Alemania
Reunión:
Conferencia; 22nd Meeting Working Group on Prolamin Analysis and Toxicity; 2007
Resumen:
Coeliac disease is a permanent gastrointestinal disorder characterised by a permanent
intolerance to a group of proteins (prolamins) present in wheat, and related cereals [1].
Histological changes in the intestinal mucosa as well as symptoms revert when
patients follow a strict diet, free of toxic proteins. Gluten-free food certification
requires both an efficient procedure for prolamin recovery from food samples and the
use of powerful quantitative methods (commonly, immunoassays).
Extraction with 60% ethanol has been the most common procedure used for prolamin
recovery from food samples. However, due to the fact that prolamins are cross-linked
through disulphide bonds to other prolamins and food matrix components, the
efficacy of extraction involving 60% ethanol is low. To increase prolamins solubility,
the use of reducing (2-mercaptoethanol) and denaturing agents (guanidine hydrochloride)
has been proposed [2]. Previous work from our laboratory showed that these
additives may affect antibody reactivity, causing interference in antigen antibody/
interaction and leading to quantitative errors [3].
Camelids produce, in addition to conventional antibodies, other molecules consisting
of homodimeric heavy chains. In these antibodies, the antigen binding site is formed
by one single domain named VHH. Under denaturing conditions, this structure is
more stable than the antigen binding site in conventional antibodies [4]. In addition,
recombinant VHH or VHH-phage from libraries are easily produced by genetic
engineering techniques [5].