The Study On Allergenicity Strength Of Milk Proteins From Three Kinds Of Milk

Dairy product is one of eight kinds of foods which could cause allergy. Several varieties of common milks, such as horse milk, cow milk and goat milk, contain allergen proteins which wouLd induce the allergy and the allergic reaction in which some active substances could be released by mast cells. However, the knowledge about the allergic intensity of three common milk proteins is insufficient. In order to compare the allergic intensity of three common milk proteins, the BALB/c allergic model in mice was established in this study.Allergenic intensity of three milk proteins was investigated in this research from the following several aspects: Spleen lymphocyte proliferation experiments; Determination of ELISA serum IgE level; Detection of plasma histamine level through detection kit; Testing various cytokines (IL-5,IL-4,IL-10,IFN-γ) level in cultivated splenic lymphocytes; Rating allergic symptoms and doing many experiments on pathoLogy in mice tissues.The secretion of cytokines was also investigated and it showed that three groups of milk proteins did not show obvious stimulation effect on the secretion of IL-4,IL-10,IFN-γ,IL-5 in splenic cell supernatant. However,β-lg, cow milk protein and goat milk protein inhibited the secretion of IL-4,IL-10,IFN-γ,IL-5 significantly. Compared with PBS group, horse milk group indicated significantly higher inhibitory effect on the secretion of IL-4,IL-10,IL-5 (P < 0.05).Allergenic intensity of three groups of milk proteins was investigated in this research through spleen lymphocyte proliferation experiments. Spleen lymphocyte proliferation effect ofβ-lg on mice fed without ConA was significantly higher than the PBS group and the horse milk (P=0.001 and P=0.001, respectively). In addition, the difference between cow milk group and PBS group was also extremely significant (P=0.002). StimuLation effect of cow milk on cell culture was higher than goat milk group and horse milk group in all experimental conditions. The difference about stimulation effect on cell culture between cow milk group and horse milk group without ConA was not significant, though the difference was significantly if the ConA was added (P<0.05).The results of serum IgE quantity determination showed that the IgE level in mice administered intragastrically withβ-lg was significantly higher than those in horse milk group and PBS group (P=0.02 and P=0.005, respectiveLy) though the difference between horse milk group and PBS group was not significant (P=0.249). However, the significant difference was found between cow milk group and PBS group (P<0.01). In addition, the difference between horse milk group andβ-lg group was significant with respect to three groups of milk proteins andβ-lg group (P<0.01). As for the release quality of histamine, difference between horse milk group and PBS group was not significant (P=0.259) while goat milk group indicated significant difference compared with other groups (P<0.01) in terms of three groups of milk proteins andβ-lg group. In addition, the significant difference was also found between horse milk group andβ-lg group (P<0.01).With respect to the rating of allergic symptoms, the mice administered intragastrically with cow milk are much more significantly serious than the other two groups. In terms of the three groups of milk proteins and PBS group, cow milk group showed significant difference though the significant difference was not found in cow milk group (P<0.05). In terms of the three groups of milk proteins andβ-lg group, the significant difference was indicated in horse milk group (P<0.05) and it proved that the allergic ability of horse milk was less than that in goat milk and cow milk.. In pathology experiments, intestinal tissue of mice in milk group indicated the highest damage degree, followed by cow milk group and then horse milk group.Innovative points in this research were described as follow: Allergenic intensity of three milk proteins was investigated through estabLishing allergic modeL in mice in this study with respect to serum IgE level, plasma histamine level, cytokine level, pathological observation, cell stimulation index, cytokine secretion and allergic symptom rating.And then the results could enrich our knowledge on signal transduction, humoral immune and development of new formuLa greatly.