Allergenicity of a hydrolyzed rice infant formula in a guinea pig model.
BACKGROUND
Because sensitization to cow's milk is a common finding in children, the identification of safe alternative protein sources is important in the management of childhood allergy.


OBJECTIVE
To evaluate, in an animal model, the allergenicity of a novel formula based on hydrolyzed rice proteins.


METHODS
We conducted an experiment involving 130 guinea pigs, from 7 to 12 days old at the onset of the study. The animals were divided into 13 groups and were given, ad libitum, one of the following liquids to drink: (1) rice hydrolysate formula (RF), (2) a conventional cow's milk formula (CMF), or (3) water. After a 37-day sensitization period, a challenge was given, consisting of an intravenous injection of either isolated proteins or ultracentrifuged formulas (uCMF and uRF). Specific IgG antibodies to beta-lactoglobulin, casein, and whole rice protein were measured by enzyme-linked immunosorbent assay.


RESULTS
When animals fed CMF were challenged with beta-lactoglobulin, casein, or whole uCMF, they showed significantly more reactions than did those fed RF when challenged with the same proteins (P < 0.001). In the groups fed RF, no reaction was observed after challenge with uRF, and only 2 mild reactions occurred after challenge with rice protein. Very low levels of specific IgG antibodies to rice protein were noted in all the groups, including the RF-fed animals, and no significant differences were evident between groups.


CONCLUSIONS
The findings suggest that this new formula based on hydrolyzed rice proteins has a very low sensitizing capability.
Piacentini
Giorgio L
GL
Clinica Pediatrica, Università di Verona, Verona, Italy. giorgio.piacentini@univr.it
Vicentini
Lucia
L
Bodini
Alessandro
A
Mazzi
Paola
P
Peroni
Diego G
DG
Maffeis
Claudio
C
Boner
Attilio L
AL
D000707:Anaphylaxis / Q000276:immunology; D000818:Animals; D000831:Animals, Newborn; D002364:Caseins / Q000276:immunology / Q000378:metabolism; D006168:Guinea Pigs; D006801:Humans; D007223:Infant; D007225:Infant Food; D007782:Lactoglobulins / Q000276:immunology / Q000378:metabolism; D016269:Milk Hypersensitivity / Q000276:immunology* / Q000517:prevention & control; D012275:Oryza / Q000276:immunology* / Q000378:metabolism; D010940:Plant Proteins / Q000097:blood / Q000276:immunology* / Q000378:metabolism; D011492:Protein Hydrolysates / Q000276:immunology* / Q000378:metabolism
D002364:Caseins; D007782:Lactoglobulins; D010940:Plant Proteins; D011492:Protein Hydrolysates