Interleukin-18 (IL-18) is a proinflammatory cytokine that plays an important role in natural killer cell activation and the T helper 1 (Th1) cell response, particularly in collaboration with IL-12. Since Th1 cells play a pivotal role in the host defense against infection with intracellular microbes, such as Leishmania major, we investigated whether IL-18 is critically involved in protection aga...

BACKGROUND Interferon (IFN)-gamma is a key to protective immunity against a variety of intracellular bacterial infections, including Chlamydia trachomatis. Interleukin (IL)-18, a recently identified Th1 cytokine, together with IL-12 is a strong stimulator for IFN-gamma production. We investigated the relative roles of IL-18 and IL- 12 in protective immunity to C. trachomatis mouse pneumonitis (...

We previously reported in ischemic acute kidney injury (AKI) in mice that caspase-1-mediated production of interleukin-18 (IL-18) is pathogenic and that macrophage depletion by liposome-encapsulated clodronate (LEC) is protective. Therefore, our aim was to determine whether macrophages are a source of IL-18 in ischemic AKI in mice. On immunofluorescence staining of the outer stripe of outer med...

Interleukin-18 (IL-18) is a proinflammatory cytokine expressed in female reproductive organs in humans, rats and mice. The physiological roles of uterine IL-18 and the regulatory mechanisms of IL-18 gene expression are unclear. The present study aimed to clarify the effects of estradiol-17beta (E2) and progesterone (P4) on IL-18 mRNA expression in the mouse uterus. Distribution and expression l...

In the periphery, IL-18 synergistically induces the expression of the Th1 cytokine IFN-gamma in the presence of IL-12 and the Th2 cytokines IL-5 and IL-13 in the presence of IL-2. Although the expression of these cytokines has been described in the thymus, their role in thymic development and function remains uncertain. We report here that freshly isolated thymocytes from C57BL/6 and BALB/c mic...

Objective. To examine the mechanism of regulation of interleukin-18 (IL-18) bioactivity by IL-18 binding protein (IL-18BP) induction. Methods. Levels of IL-18 and IL-18BPa in synovial fluid samples from patients with osteoarthritis (OA) or rheumatoid arthritis (RA) were determined by enzyme-linked immunosorbent assays (ELISAs), followed by calculation of free IL-18. IL-18 and IL-18BPa synthesis...