We studied the effect of various
amino acid mixtures on nasal
allergy induced by the intranasal application of
toluene diisocyanate (TDI) in mice. In Experiment 1 (Exp. 1), mice were fed a 25%
casein,
soy protein isolate (SPI),
egg white protein (EW) or
gluten diet. In Experiment 2 (Exp. 2), mice were fed a 25%
amino acid mixture diets patterned after
casein (AA-
casein), SPI (AA-SPI), EW
protein (AA-EW) or
gluten (AA-
gluten). In Experiment 3 3 (Exp. 3) we modified the
glutamine/
glutamic acid (Gln/Glu) concentrations in the
amino acid mixtures. Mice were fed a 25% AA-SPI, low Gln/Glu AA-SPI (LG-AA-SPI), AA-EW or high Gln/Glu AA-EW (HG-AA-EW) diet. At the 5th week, mice were divided into sensitized (sen-) and non-sensitized (ns-) groups. The mice in sensitized groups were treated with two courses of intranasal application of
toluene diisocyanate (TDI) in
ethyl acetate for 5 consecutive days, separated by 9 days rest. The non-sensitized groups of mice were treated with a vehicle. Nine days after the second sensitization, all mice were provoked by TDI. Nasal responses and serum
IgE concentration were studied. The findings of Exp. 1 showed that the sen-EW group exhibited a lower
body weight gain, higher nasal symptom score and higher
IgE concentration than the other sensitized groups. The findings dings of Exp. 2 showed that the sen-EW group had a lower
body weight gain, higher nasal symptom score and higher
IgE concentration than the other sensitized groups. In Exp. 3, the AA-EW group showed a higher total nasal score and
IgE concentration than the HG-AA-EW group, however, the findings of LG-AA-SPI and AA-SPI were similar. These findings demonstrated that
amino acid mixtures affect nasal
allergy induced by the intranasal application of TDI in mice.