Does an IgG4-targeted exclusion diet improve CD symptoms?

About IgG4 antibody-mediated immunity

Metametrix's Allergix IgG4 Antibodies 90 - serum
"IgG4 antibodies are associated with non-atopic or "delayed" food reactions...."
Common offending foods:  milk, corn, wheat, eggs, foods processed with moulds (black teas, breads, fruit juices)
Also see Downloads section (bottom right) for Allergix Antibody Profiles, IgG4 Food Antibody Interpretation

"Anti-Inflammatory Activity of Human IgG4 Antibodies by Dynamic Fab Arm Exchange" in Science (2007)
Conclusions:  "In summary, antibodies of the IgG4 isotype are shown to be dynamic molecules, undergoing Fab arm exchange in vivo and in vitro. The ability to engage in Fab arm exchange appears to be an inherent feature of IgG4 that involves the third constant domain in addition to the hinge region and that only requires a reducing environment to be activated. This novel protein modification challenges the commonly accepted one antibody–one antigen paradigm and redefines our thinking about the role of IgG4 in antibody-mediated immunity and the application of IgG4 monoclonal antibodies to immunotherapy."

IgG4 in IBS

"Food-specific IgG4 antibody-guided exclusion diet improves symptoms and rectal compliance in irritable bowel syndrome." in Scand J Gasterol (2005)
Results:  "IgG4 antibodies to milk, eggs, wheat, beef, pork and lamb were commonly elevated."
Conclusions:  "Food-specific IgG4 antibody-guided exclusion diet improves symptoms in IBS and is associated with an improvement in rectal compliance."

IgG4 in CD

"Food specific IgG4 -guided exclusion diets improve symptoms in Crohn’s disease: A pilot study" in Colorectal Disease (2010)
Conclusions:  "IgG4-guided exclusion diets resulted in significant symptomatic improvement with an objective fall in an inflammatory marker. This approach may be useful in clinical practice."

"Clinical Relevance of IgG Antibodies against Food Antigens in Crohn’s Disease: A Double-Blind Cross-Over Diet Intervention Study" in Digestion (2010)
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."