Lactobacillus Acidophilus Strain L-92 Regulates the Production of Th1 Cytokine as well as Th2 Cytokines

ABSTRACTBackgroundThere is growing interest in probiotics such as lactic acid bacteria (LAB), not only for treatment of T helper type (Th) 1-mediated diseases but also for Th2-mediated diseases, including allergic diseases, since lactic acid bacteria may be able to modulate the Th1/Th2 balance, in addition to having an immunomodulative effect through induction of Th1 bias.MethodsThe effect of oral administration of heat-killed Lactobacillus acidophilus Strain L-92 (L-92) on ovalbumin (OVA)-specific immunoglobulin (Ig)E production was investigated in BALB/c mice. L-92 was orally administered to mice for 8 weeks from 2 weeks after initiation of OVA-immunization. Patterns of cytokine and Ig production in splenocytes and cells from Peyer’s patches (PPs) from these mice were examined after restimulation with OVA in vitro.ResultsL-92 significantly suppressed serum OVA-specific IgE levels for a long period. Cytokines such as interferon (IFN)-γ, interleukin (IL)-4 and IL-10 and Igs such as total IgE and OVA-specific IgE were produced at significantly lower levels by splenocytes of L-92-treated mice, compared with those of control mice. In contrast, transforming growth factor (TGF)-β and IgA levels produced by PPs from L-92-treated mice were significantly higher than in those from control mice.ConclusionsOral L-92 administration regulated both Th1 and Th2 cytokine responses, suppressed serum OVA-specific IgE, and induced TGF-β production in PPs. TGF-β is known to be associated with activation of regulatory T (Treg) cells. These data suggest that LAB may have immunomodulative effect by Treg cells via TGF-β activity

Kampo Medicines for Mite Antigen-Induced Allergic Dermatitis in NC/Nga Mice

We have established an allergic dermatitis model in NC/Nga mice by repeated local exposure of mite antigen for analyzing atopic dermatitis. We examined how four Kampo medicines, Juzen-taiho-to, Hochu-ekki-to, Shofu-san and Oren-gedoku-to, on the dermatitis model to obtain basic information on their usefulness for treating atopic dermatitis. Mite antigen (Dermatophagoides farinae crude extract) solution at a concentration of 10 mg/ml was painted on the ear of NC/Nga mice after tape stripping. The procedure was repeated five times, at 7 day intervals. An apparent biphasic ear swelling was caused after the fourth and fifth antigen exposures with elevated serum IgE levels and accumulation of inflammatory cells. In the cervical lymph nodes and ear lobes, the five procedures of antigen exposure induced interleukin-4 mRNA expression but reduced interferon-γ mRNA expression. Oral administration of all four Kampo medicines inhibited the formation of ear swelling and inflammatory cell accumulation. Juzen-taiho-to and Hochu-ekki-to apparently prevented the elevation of serum IgE level. Furthermore, the four Kampo medicines showed a tendency to prevent not only the increase in interleukin-4 mRNA expression but also the decrease in interferon-γ mRNA expression. The present results indicate that Juzen-taiho-to, Hochu-ekki-to, Shofu-san and Oren-gedoku-to may correct the Th1/Th2 balance skewed to Th2, and this activity helps inhibit dermatitis in NC/Nga mice. The ability of the Kampo medicines to correct the Th1/Th2 balance seems to underlie their effectiveness in treating of atopic dermatitis