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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 CD8+ CD11b+ TCRγ/δ+ 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 × 106 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+ TCRα/β+ 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 μg/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... [ABSTRACT FROM AUTHOR]

Summary Interleukins (IL) regulate differentT-cell surface Ag known as activation markers that have distinct functionalroles. In this paper, while studying the influence of some cytokines(IL-12, IL-2 and IL-4) on the expression of several markers [CD69,CD25, CD26, CD3, human leukocyte antigen (HLA-DR), CD45R0] in in vitro activatedhuman T lymphocytes, we observed two groups of donors respondingto phytohaemagglutinin (PHA) activation with high or low HLA-DRAg expression. We also found that CD4 and CD8 populations had differentHLA-DR densities under PHA activation (particularly the high HLA-DR-expressinggroup). Interleukins, in a dose-dependent manner (IL-2 partially),upregulated these HLA-DR levels. In 5 day cultures, IL-12and IL-2 enhanced the CD8/CD4 ratio of activated T cells,which was responsible, in part, for the IL-dependent HLA-DR upregulation.IL-12 and IL-2 also upregulated the HLA-DR expression at the molecularlevel on CD8, and IL-12 downregulated it on CD4 cells. It seemsthat IL-4 upregulated HLA-DR by shortening the mitogen-dependent regulationkinetics. We hypothesize that the different effect of each IL onHLA-DR expression might be related to the regulation of the doseof antigenic peptide presentation and, thus, also influence TH1 /TH2 dominance. [ABSTRACT FROM AUTHOR]

SummaryFlaky skin (fsn) is an autosomal recessive mutation on mouse chromosome 17 that causes severe anaemia, forestomach papillomatosis and a papulosquamous skin disease that resembles psoriasis in humans. In the present paper, it is reported that fsn causes peripheral lymphadenopathy, CD4/CD8 imbalance and hyperresponsiveness to T cell growth factors. Peripheral lymph nodes (PLN) of adult mutant (fsn/fsn) mice were found to contain almost 10-fold more leucocytes than PLN from phenotypically normal littermates (+/fsn or +/+, hereafter referred to as +/?). Analysis of PLN cells using mAbs and flow cytometry revealed that this predominantly lymphoid hyperplasia was characterized by approximately equivalent increases in the numbers of CD3+ T cells and CD19+ B cells. However, expansion within the T cell compartment was non-random, because fsn/fsn PLN had a considerably reduced ratio of CD4+ to CD8+ T cells (1.08 ± 0.37) compared to +/? PLN (2.47 ± 0.44, P < 0.0001). In vitro assays of cellular proliferation in response to T and B cell growth factors showed that fsn/fsn PLN cells were hyperresponsive to IL-2, IL-4 and IL-7 when compared with PLN cells from +/? mice. Studies using mesenteric lymph node and peripheral blood cells showed that hyperresponsive cells are widely distributed in fsn/fsn mice. Experiments in newborn mice showed that the lymphoid disturbances caused by fsn are established at least as early as 2 weeks of age, a time that precedes the onset of the earliest clinical skin lesions. These data implicate a role for the fsn gene product in regulating the size and content of the peripheral lymphoid compartment. [ABSTRACT FROM AUTHOR]