Amelioration Effect of Lactobacillus kefiranofaciens ZW3 on Ovalbumin-Induced Allergic Symptoms in BALB/c Mice

Abstract

Previous studies have shown that supplementation with specific probiotics can be used to alleviate allergy symptoms. The purpose of this study was to evaluate the anti-allergic effects of Lactobacillus kefiranofaciens ZW3 (ZW3) in ovalbumin (OVA)-induced allergic mice. The mice were divided into six groups: the food allergy group, positive group (Lactobacillus rhamnosus GG), low-dose ZW3 group, middle-dose ZW3 group, high-dose ZW3 group, and the control group involving healthy mice. BALB/c mice were intraperitoneally injected with OVA/complete Freund's adjuvant (CFA) for allergy sensitization. Probiotics were administered orally once every two days in the probiotic-treated groups. The allergic score, serum OVA-sIgE, body mass, thymus, and spleen indexes were detected on day 22, and the relative mRNA expression of inflammatory cytokines was detected via RT-qPCR. The results suggest that the body weight and thymus index returned to normal levels; allergy scores, serum OVA-sIgE, IL-4, IL-5, and IL-10 expression decreased; and IFN-γ and IL-2 increased significantly in the ZW3 group compared with the allergy group. Furthermore, ZW3 decreased Muribaculaceae and Ruminococcaceae abundance and increased Lachnospiraceae abundance in the intestinal flora. In summary, ZW3 induced anti-allergic effects by increasing Th1 cytokines and decreasing Th2 cytokines, which can remarkably ameliorate the symptoms of an ovalbumin-induced food allergy.

Keywords: Lactobacillus kefiranofaciens; Th1/Th2 balance; allergic symptoms; intestinal flora.

Figure 1

(A) Establishment of OVA-sensitized mice model. Serum total IgE levels in control group and OVA group during sensitization (B) and serum OVA-sIgE levels in all groups (C). ^## indicates statistically significant difference compared with normal group at p < 0.01. ** represents statistically significant difference compared with OVA group at p < 0.01.

Figure 2

The allergic symptoms (A), body mass (B), and spleen and thymus indexes (C) in all groups. ^# and ^## indicate statistically significant differences compared with control group at p < 0.05 and p < 0.01, respectively. ** represents statistically significant difference compared with OVA group at p < 0.01.

Figure 3

Relative mRNA expression of IL-2 (A), IFN-γ (B), IL-4 (C), IL-5 (D), IL-10 (E), and IL-13 (F) in spleen in treated and OVA mice. * and ** indicate statistically significant compared with OVA group at p < 0.05 and p < 0.01, respectively.

Figure 4

ZW3 modulates intestinal flora in OVA-sensitized mice. Shannon index (A) and Simpson index (B), reflecting the α-diversity of intestinal flora. (C) PCoA analysis reflecting the β-diversity of intestinal flora. (D) Bacterial composition at the phylum level. (E) B/F radio. (F) Bacterial composition at the family level.