Age-dependent changes of B cell and T cell-mediated immune responses in naive C3H/HeJ mice under regular mouse chow feeding conditions

Oh, Se Jo; Lee, Kyung Won; Jeon, Gye Ree; Lee, Ki Sun; Lee, Soo Young

Abstract

BACKGROUND AND OBJECTIVE: Murine system for studying allergic diseases has been popular in the fields of food allergy and development of their therapeutic strategies. However, there has been no information about the age-dependent changes of natural immune responses of naive C3H/HeJ mice. The purpose of this study was to evaluate the age-dependent changes of B and T-cell mediated immunologic parameters in naive C3H/HeJ mice, which can provide information for experimental planning and analysis of research results.
SUBJECTS AND METHODS
Eight naive, female, 5-week-old C3H/HeJ mice were grown under the regular mouse chow feeding conditions for 6 weeks. Sera were obtained at week (w) 5, w6, w8 and w10 for measuring total and chow-specific IgE, IgG1 and IgG2a antibodies. Splenocyte proliferation (at w8 and w10) and cytokine production (at w6, w8 and w10) were evaluated with or without Con A stimulation with pooled splenocytes from two mice of each age group. Serum antibodies and cytokines (IL-4, IL-5, IL-12, INF-gamma, TGF-beta1) were measured by ELISA. Using RT-PCR, IL-4 and INF-gamma mRNA expressions were measured in Peyer's patch and spleen tissue at w10.
RESULTS
The levels of total IgE and IgG1 were increased by age while the level of IgG2a was decreased. Chow-specific IgE and IgG2a responses were neglectable through out the whole experimental period (20-30 ng/ml or less). Chow-specific IgG1 levels were measured in the significant concentrations (200-300 ng/ml) but there was no age-dependent change through out the experiment. Con A stimulated-splenocyte proliferation indexes were variable according to the culture-durations and ages of mice. The higher proliferation indexes were observed in the wells receiving thymidine pulse at 48-hour culture, especially in the mice at w10. Con A stimulated IL-4 production in the 72-hour splenocyte culture supernatant was significantly increased at w8, and w10 while INF-gamma production increased only at w10. The changes in the production of IL-5, IL-12 and TGF-beta did not provide significant information in the present study. The ratio of IL-4/IFN-gamma mRNA expression was higher in Peyer's patch than in the spleen.
CONCLUSION
The changes of B-cell and T-cell mediated immunologic parameters were complex and variable according to the age in naive C3H/HeJ mice under regular chow feeding conditions. For that reason, the information from the present study needs to be considered in the course of planning or analysing research/data using murine systems.