In vitro hydrolysis of gliadin and casein peptides: secondary defect in coeliac disease shown by organ culture.
BACKGROUND
Small-intestinal organ culture was used as an in vitro model of coeliac disease, studying biopsy specimens from patients with coeliac disease, cow's milk allergy, and controls.


METHODS
Organ culture incubations were done using the pure gliadin peptide B3144 (amino acid sequences 3-56 of alpha-type gliadins) and a control peptide from casein (amino acid sequences 152-193 of alpha s1-casein). The importance of using negative controls was stressed by non-specific tissue damage. By reversed-phase high-performance liquid chromatography of organ culture supernatants, 27 specimens were further investigated.


RESULTS
There was good retrieval of peptide calibration peaks after culture. Qualitative and quantitative evaluation of chromatography runs showed degradation of at least 29% of B3144 and 37% of Cas-P. Normal mucosa (controls and coeliac patients on a gluten-free diet) was able to hydrolyse peptide fractions completely, whereas incubation with damaged mucosa (coeliac disease, cow's milk allergy) left initial peptides.


CONCLUSIONS
It is concluded, using a pure single gliadin peptide, that deficient peptide hydrolysis in coeliac disease was a secondary event.
Walz
F
F
Paediatric Gastroenterology and Nutrition Group, Universitaets-Kinderklinik, Tubingen, Garching, Germany.
Wieser
H
H
Stern
M
M
D000293:Adolescent; D000328:Adult; D002364:Caseins / Q000378:metabolism*; D002446:Celiac Disease / Q000178:diet therapy / Q000378:metabolism*; D002648:Child; D002675:Child, Preschool; D002851:Chromatography, High Pressure Liquid; D005903:Gliadin / Q000378:metabolism*; D006801:Humans; D006868:Hydrolysis; D007223:Infant; D007421:Intestine, Small / Q000378:metabolism*; D016269:Milk Hypersensitivity / Q000378:metabolism; D009924:Organ Culture Techniques
D002364:Caseins; D005903:Gliadin