[Inhibition of antigen-specific T helper type 2 responses by Perilla frutescens extract].
Perilla frutescens leaf extract (PFE) is known as a natural medicine with anti-allergic activities, although its mechanism of action remains unclear. In this study, we examined the effect of PFE on antigen-specific antibody and on cytokine production. Mice were immunized three times (weekly) with sugi basic protein (SBP), a major allergen of Japanese cedar pollen, in alum adjuvant. PFE was injected intraperitoneally into mice on day 2 before and on the day of each immunization with SBP in alum adjuvant. Serum anti-SBP IgE and IgG 1 antibody levels were significantly suppressed in mice injected with PFE. Furthermore, the production of interleukin (IL)-4, IL-5 and IL-10 by SBP-stimulated splenocyses also decreased in PFE-injected mice in a dose-dependent manner. However, PFE had no effect on either the serum anti-SBP IgG 2 a antibody levels or on interferon (INF)-gamma production by splenocytes. When splenocytes were stimulated with concanavalin A, there was no difference in cytokine production between mice injected with PFE and control mice injected with vehicle. SBP-specific T cell line established in the presence of PFE from the lymph node cells of mice immunized with SBP showed reduced IL-4, IL-5 and IL-10 production compared with that established in the absence of PFE. In contrast, comparable levels of IFN-gamma production were observed between these two T cell lines. These data suggest that PFE down-regulates Th 2-type cytokine production and prevents the Th 1/Th 2 balance from polarizing toward Th 2-type immune responses.
Ishihara
T
T
Fujisaki Institute, Hayashibara Biochemical Laboratories, Inc.
Okamoto
I
I
Masaki
N
N
Kohno
K
K
Tanimoto
T
T
Ikegami
H
H
Kurimoto
M
M
D000818:Animals; D000917:Antibody Formation / Q000187:drug effects; D016207:Cytokines / Q000096:biosynthesis; D005260:Female; D019686:Lamiaceae; D051379:Mice; D008807:Mice, Inbred BALB C; D010936:Plant Extracts / Q000494:pharmacology; D010946:Plants, Medicinal; D006377:T-Lymphocytes, Helper-Inducer / Q000187:drug effects* / Q000276:immunology
D016207:Cytokines; D010936:Plant Extracts