Clinical relevance of IgG antibodies against food antigens in Crohn's disease: a double-blind cross-over diet intervention study.
BACKGROUND
Environmental factors are thought to play an important role in the development of Crohn's disease (CD). Immune responses against auto-antigens or food antigens may be a reason for the perpetuation of inflammation.


METHODS
In a pilot study, 79 CD patients and 20 healthy controls were examined for food immunoglobulin G (IgG). Thereafter, the clinical relevance of these food IgG antibodies was assessed in a double-blind cross-over study with 40 patients. Based on the IgG antibodies, a nutritional intervention was planned. The interferon (IFN)gamma secretion of T cells was measured. Eosinophil-derived neurotoxin was quantified in stool.


RESULTS
The pilot study resulted in a significant difference of IgG antibodies in serum between CD patients and healthy controls. In 84 and 83% of the patients, respectively, IgG antibodies against processed cheese and yeast were detected. The daily stool frequency significantly decreased by 11% during a specific diet compared with a sham diet. Abdominal pain reduced and general well-being improved. IFNgamma secretion of T cells increased. No difference for eosinophil-derived neurotoxin in stool was detected.


CONCLUSIONS
A nutritional intervention based on circulating IgG antibodies against food antigens showed effects with respect to stool frequency. The mechanisms by which IgG antibodies might contribute to disease activity remain to be elucidated.
Division of Gastroenterology and Hepatology, University Hospital Zurich, Zurich, Switzerland.
S
S
Bentz
M
M
Hausmann
H
H
Piberger
S
S
Kellermeier
S
S
Paul
L
L
Held
W
W
Falk
F
F
Obermeier
M
M
Fried
J
J
Schölmerich
G
G
Rogler
D015746:Abdominal Pain / Q000503:physiopathology; D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D000888:Antibodies, Anti-Idiotypic / Q000276:immunology*; D003424:Crohn Disease / Q000097:blood / Q000178:diet therapy* / Q000276:immunology*; D018592:Cross-Over Studies; D003672:Defecation / Q000502:physiology; D018450:Disease Progression; D004311:Double-Blind Method; D004797:Enzyme-Linked Immunosorbent Assay; D047208:Eosinophil-Derived Neurotoxin / Q000032:analysis / Q000276:immunology; D005243:Feces; D005260:Female; D005502:Food; D005512:Food Hypersensitivity / Q000276:immunology*; D006304:Health Status; D006801:Humans; D007074:Immunoglobulin G / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D011336:Probability; D011379:Prognosis; D012008:Recurrence; D012016:Reference Values; D018570:Risk Assessment; D016896:Treatment Outcome; D055815:Young Adult
D000888:Antibodies, Anti-Idiotypic; D007074:Immunoglobulin G; D047208:Eosinophil-Derived Neurotoxin