aconitine and Burns

IL-12 is an inducer of type 1 T cell responses, which are essential in host defense against herpes simplex virus type 1 (HSV-1) infection. However, type 1 T cell responses are not elicited by IL-12 in thermally injured mice (TI-mice) that routinely have a predominance of burn-associated type 2 T cell responses. In our previous studies, benzoylmesaconine (BEN, an aconitine derivative extracted from heated-Aconiti tuber) induced the generation of CD4+ T cells antagonistic to type 2 T cells (BEN-CD4+ T cells). In the present study, the effects of a combination therapy using IL-12 and BEN to treat severe HSV-1 infection in TI-mice were investigated. When TI-mice were treated with either IL-12 (500 U per mouse) or BEN (1 microg/kg) alone, they did not resist HSV-1 infection. However, 60-80% of TI-mice exposed to HSV-1 survived after they received IL-12 and BEN or BEN-CD4+ T cells in combination. After stimulation with anti-CD3 mAb in vitro, IFN- was not produced in cultures of splenic T cells from TI-mice exposed to HSV-1 and treated with either IL-12, BEN or BEN-CD4+ T cell alone. However, IFN- production was induced by the mAb stimulation in the cultures of T cells from infected mice treated with IL-12 and BEN or BEN-CD4+ T cells in combination. These results suggest that the combination therapy of IL-12 (an inducer of type 1 T cell responses) and BEN (an inhibitor of type 2 T cell responses) may protect TI-mice from severe HSV-1 infection.

Topics: Aconitine; Adjuvants, Immunologic; Animals; Burns; Herpesviridae Infections; Interferon-gamma; Interleukin-12; Interleukin-4; Mice; Mice, Inbred BALB C; Muromegalovirus; Th1 Cells; Th2 Cells

As compared with normal unburned mice, thermally injured mice have been shown to be 50-100 times more susceptible to HSV type 1 (HSV-1) or Candida albicans infection. Benzoylmesaconine (BEN) improved the resistance of thermally injured mice against infection with HSV-1 or C. albicans to the level observed in normal mice. Mortality rates of normal mice exposed to lethal amounts of these pathogens were not affected by the BEN treatment, while significant survival effects were produced in these mice after treatment with acyclovir (against HSV-1) or amphotericin B (against C. albicans). Benzoylmesaconine did not inhibit the growth of these pathogens in vitro and did not directly reduce the viability of the pathogens. However, burned mice inoculated with CD4+ T cells from BEN-treated mice resisted infections from these pathogens. These results suggested that, through the generation of CD4+ T cells, BEN recovered the impaired resistance of thermally injured mice to infection by HSV-1 or C. albicans.

Topics: Aconitine; Adoptive Transfer; Animals; Burns; Candidiasis; CD4-Positive T-Lymphocytes; Herpes Simplex; Herpesvirus 1, Human; Hydrolysis; Immunity, Innate; Mice; Mice, Inbred BALB C; Spleen

In the accompanying paper, the resistance to infections with HSV type 1 (HSV-1) and Candida albicans was improved in thermally injured mice treated with benzoylmesaconine (BEN), an aconitine-hydrolysate isolated from heated Aconiti tuber, or inoculated with splenic CD4+ T cells from BEN-treated mice (BEN T cells). In this paper, therefore, the antiviral mechanism of BEN T cells (or BEN) on the improved resistance of burned mice to the HSV-1 infection was studied. Burn-associated CD + CD11b+ TCRgamma/delta+ type-2 T cells have been shown to be a key on the increased susceptibility of thermally injured mice to infection with HSV-1 or C. albicans. The susceptibility of T6S-mice, mice inoculated with 1 x 10(6) cells/mouse of T6S cells (a clone of burn-associated type-2 T cells), to HSV-1 infection was similar to that of thermally injured mice. The adoptive transfer of BEN T cells to T6S-mice restores their impaired resistance to HSV-1 infection. The type-2 cytokine levels in sera of T6S-mice were decreased after inoculation of BEN T cells. BEN T cells inhibited the type-2 cytokine production by T6S cells when they were cocultured in vitro. BEN T cells, characterized as CD4+ CD28+ TCRalpha/beta+ Vicia villosa (VV) lectin-adherent T cells, showed non-specific ability to inhibit the cytokine production by various type-2 T cells. From the results of the cytokine-producing profile, BEN T cells were shown to be a different subset of CD4+ T cells from Th1 and Th2 cells, although these three CD4+ T cells had similar properties phenotypically. BEN T cells were induced in normal mice 1-4 days after the oral treatment of BEN (1 microg/kg or more). These results suggest that, through the induction of antagonistic CD4+ T cells against burn-associated type-2 T cells, BEN may improve the resistance of T6S-mice (or thermally injured mice) to the infection of HSV-1.

Topics: Aconitine; Animals; Burns; Candida albicans; Candidiasis; CD4-Positive T-Lymphocytes; Clone Cells; Cytokines; Disease Susceptibility; Herpes Simplex; Herpesvirus 1, Human; Hydrolysis; Immunophenotyping; Lymphocyte Activation; Mice; Mice, Inbred BALB C; T-Lymphocyte Subsets