Detection And Significance Of Serum IL-4and IFN-γ In Ovalbumin Sensitized Young Rats

Objective：Observe the changes of serum IL-4and IFN-γ levels and IL-4/IFN-γ ratio in3weeks old SD young rats of food allergy（FA）animal models before sensitization, allergensstimulate challenge, learn about the activation of TH1、TH2cells and investigate the role andsignificance of them in food allergy development.Methods：16clean-level weaning female SD young rats of3weeks old were randomlydevided into2groups by random digits table: food allergy group (n=8) and control group (n=8). SD young rats OVA food allergy models were established by low-dose ovalbumin (OVA)injected intraperitoneally to sensitize and high-dose OVA gave intragastric administration tochallenge. Observe2groups SD young rats changes in weight and activities before allergysensitize and after challenge; changes in the serum OVA-IgE and the morphological of theintestinal mucosa after the last challenge, evaluate the young rats food allergy models.ELISAwas used to continuously measured the IL-4, IFN-γ levels in the two groups young rats beforeallergy sensitize and after challenge.SPSS13.0software package for atistical analysis, the significance test standards is α=0.05.Results: FA young rats manifested the vertical hair, loss of gloss, activity decreased,irritability, and loose stools, after the last challenge, compared with the NS group, weight ofSD young rats in the FA group were trend to loss; compared with the NS group, in FA groupSD young rats had more inflammatory cells infiltration and eosinophil cells in villus stroma.The serum OVA-IgE level in FA group young rats significantly increased after challenge,compared with the NS group, the differences were statistically significant (P＜0.01); Beforesensitization、 after challenge the serum IL-4level (ng/L) in FA group young ratswere36.375±4.312、71.075±10.055, in NS group were35.394±3.635、41.590±6.757, theserum IL-4level was no significant difference in two groups young rats before sensitization, theserum IL-4level in FA group significantly increased after challenge, compared with the NSgroup, the differences were statistically significant (P＜0.01); Before sensitization、afterchallenge the serum IFN-γ level(ng/L) in FA group young rats were100.849±9.052、259.146±54.008, in NS group were100.164±18.496、115.654±18.428, the serum IFN-γ level was no significant difference in two groups young rats before sensitization, the serum IFN-γlevel in FA group significantly increased after challenge, compared with the NS group, thedifferences were statistically significant (P＜0.01); more challenge, the serum IL-4and IFN-γlevels in FA group young rats were gradually increased, and they were at the peak after the lastchallenge, the serum IL-4and IFN-γ levels were significantly increased at the same time aftereach challenge in FA group SD young rats compared with NS group; before sensitization, andafter challenge,the serum IL-4/IFN-γ ratio in FA group young rats compared with the serumIL-4/IFN-γ ratio in N S group young rats were no significant difference (P＞0.05).Conclusion：Food allergy young animal models can be established by ovalbumin (OVA)injected intraperitoneally to sensitize and intragastric administration to challenge. The studysuggested that TH2and TH1cells were in a high functional status，there may be IgE-mediatedhumoral immune response and cell-mediated delayed type hypersensitivity in the FA younganimal models.